Line data Source code
1 : /*-------------------------------------------------------------------------
2 : *
3 : * clauses.c
4 : * routines to manipulate qualification clauses
5 : *
6 : * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group
7 : * Portions Copyright (c) 1994, Regents of the University of California
8 : *
9 : *
10 : * IDENTIFICATION
11 : * src/backend/optimizer/util/clauses.c
12 : *
13 : * HISTORY
14 : * AUTHOR DATE MAJOR EVENT
15 : * Andrew Yu Nov 3, 1994 clause.c and clauses.c combined
16 : *
17 : *-------------------------------------------------------------------------
18 : */
19 :
20 : #include "postgres.h"
21 :
22 : #include "access/htup_details.h"
23 : #include "access/table.h"
24 : #include "catalog/pg_class.h"
25 : #include "catalog/pg_inherits.h"
26 : #include "catalog/pg_language.h"
27 : #include "catalog/pg_operator.h"
28 : #include "catalog/pg_proc.h"
29 : #include "catalog/pg_type.h"
30 : #include "executor/executor.h"
31 : #include "executor/functions.h"
32 : #include "funcapi.h"
33 : #include "miscadmin.h"
34 : #include "nodes/makefuncs.h"
35 : #include "nodes/multibitmapset.h"
36 : #include "nodes/nodeFuncs.h"
37 : #include "nodes/subscripting.h"
38 : #include "nodes/supportnodes.h"
39 : #include "optimizer/clauses.h"
40 : #include "optimizer/cost.h"
41 : #include "optimizer/optimizer.h"
42 : #include "optimizer/pathnode.h"
43 : #include "optimizer/plancat.h"
44 : #include "optimizer/planmain.h"
45 : #include "parser/analyze.h"
46 : #include "parser/parse_coerce.h"
47 : #include "parser/parse_collate.h"
48 : #include "parser/parse_func.h"
49 : #include "parser/parse_oper.h"
50 : #include "parser/parsetree.h"
51 : #include "rewrite/rewriteHandler.h"
52 : #include "rewrite/rewriteManip.h"
53 : #include "tcop/tcopprot.h"
54 : #include "utils/acl.h"
55 : #include "utils/builtins.h"
56 : #include "utils/datum.h"
57 : #include "utils/fmgroids.h"
58 : #include "utils/json.h"
59 : #include "utils/jsonb.h"
60 : #include "utils/jsonpath.h"
61 : #include "utils/lsyscache.h"
62 : #include "utils/memutils.h"
63 : #include "utils/rel.h"
64 : #include "utils/syscache.h"
65 : #include "utils/typcache.h"
66 :
67 : typedef struct
68 : {
69 : ParamListInfo boundParams;
70 : PlannerInfo *root;
71 : List *active_fns;
72 : Node *case_val;
73 : bool estimate;
74 : } eval_const_expressions_context;
75 :
76 : typedef struct
77 : {
78 : int nargs;
79 : List *args;
80 : int *usecounts;
81 : } substitute_actual_parameters_context;
82 :
83 : typedef struct
84 : {
85 : int nargs;
86 : List *args;
87 : int sublevels_up;
88 : } substitute_actual_parameters_in_from_context;
89 :
90 : typedef struct
91 : {
92 : char *proname;
93 : char *prosrc;
94 : } inline_error_callback_arg;
95 :
96 : typedef struct
97 : {
98 : char max_hazard; /* worst proparallel hazard found so far */
99 : char max_interesting; /* worst proparallel hazard of interest */
100 : List *safe_param_ids; /* PARAM_EXEC Param IDs to treat as safe */
101 : } max_parallel_hazard_context;
102 :
103 : static bool contain_agg_clause_walker(Node *node, void *context);
104 : static bool find_window_functions_walker(Node *node, WindowFuncLists *lists);
105 : static bool contain_subplans_walker(Node *node, void *context);
106 : static bool contain_mutable_functions_walker(Node *node, void *context);
107 : static bool contain_volatile_functions_walker(Node *node, void *context);
108 : static bool contain_volatile_functions_not_nextval_walker(Node *node, void *context);
109 : static bool max_parallel_hazard_walker(Node *node,
110 : max_parallel_hazard_context *context);
111 : static bool contain_nonstrict_functions_walker(Node *node, void *context);
112 : static bool contain_exec_param_walker(Node *node, List *param_ids);
113 : static bool contain_context_dependent_node(Node *clause);
114 : static bool contain_context_dependent_node_walker(Node *node, int *flags);
115 : static bool contain_leaked_vars_walker(Node *node, void *context);
116 : static Relids find_nonnullable_rels_walker(Node *node, bool top_level);
117 : static List *find_nonnullable_vars_walker(Node *node, bool top_level);
118 : static void find_subquery_safe_quals(Node *jtnode, List **safe_quals);
119 : static bool is_strict_saop(ScalarArrayOpExpr *expr, bool falseOK);
120 : static bool convert_saop_to_hashed_saop_walker(Node *node, void *context);
121 : static Node *eval_const_expressions_mutator(Node *node,
122 : eval_const_expressions_context *context);
123 : static bool contain_non_const_walker(Node *node, void *context);
124 : static bool ece_function_is_safe(Oid funcid,
125 : eval_const_expressions_context *context);
126 : static List *simplify_or_arguments(List *args,
127 : eval_const_expressions_context *context,
128 : bool *haveNull, bool *forceTrue);
129 : static List *simplify_and_arguments(List *args,
130 : eval_const_expressions_context *context,
131 : bool *haveNull, bool *forceFalse);
132 : static Node *simplify_boolean_equality(Oid opno, List *args);
133 : static Expr *simplify_function(Oid funcid,
134 : Oid result_type, int32 result_typmod,
135 : Oid result_collid, Oid input_collid, List **args_p,
136 : bool funcvariadic, bool process_args, bool allow_non_const,
137 : eval_const_expressions_context *context);
138 : static Node *simplify_aggref(Aggref *aggref,
139 : eval_const_expressions_context *context);
140 : static List *reorder_function_arguments(List *args, int pronargs,
141 : HeapTuple func_tuple);
142 : static List *add_function_defaults(List *args, int pronargs,
143 : HeapTuple func_tuple);
144 : static List *fetch_function_defaults(HeapTuple func_tuple);
145 : static void recheck_cast_function_args(List *args, Oid result_type,
146 : Oid *proargtypes, int pronargs,
147 : HeapTuple func_tuple);
148 : static Expr *evaluate_function(Oid funcid, Oid result_type, int32 result_typmod,
149 : Oid result_collid, Oid input_collid, List *args,
150 : bool funcvariadic,
151 : HeapTuple func_tuple,
152 : eval_const_expressions_context *context);
153 : static Expr *inline_function(Oid funcid, Oid result_type, Oid result_collid,
154 : Oid input_collid, List *args,
155 : bool funcvariadic,
156 : HeapTuple func_tuple,
157 : eval_const_expressions_context *context);
158 : static Node *substitute_actual_parameters(Node *expr, int nargs, List *args,
159 : int *usecounts);
160 : static Node *substitute_actual_parameters_mutator(Node *node,
161 : substitute_actual_parameters_context *context);
162 : static void sql_inline_error_callback(void *arg);
163 : static Query *inline_sql_function_in_from(PlannerInfo *root,
164 : RangeTblFunction *rtfunc,
165 : FuncExpr *fexpr,
166 : HeapTuple func_tuple,
167 : Form_pg_proc funcform,
168 : const char *src);
169 : static Query *substitute_actual_parameters_in_from(Query *expr,
170 : int nargs, List *args);
171 : static Node *substitute_actual_parameters_in_from_mutator(Node *node,
172 : substitute_actual_parameters_in_from_context *context);
173 : static bool pull_paramids_walker(Node *node, Bitmapset **context);
174 :
175 :
176 : /*****************************************************************************
177 : * Aggregate-function clause manipulation
178 : *****************************************************************************/
179 :
180 : /*
181 : * contain_agg_clause
182 : * Recursively search for Aggref/GroupingFunc nodes within a clause.
183 : *
184 : * Returns true if any aggregate found.
185 : *
186 : * This does not descend into subqueries, and so should be used only after
187 : * reduction of sublinks to subplans, or in contexts where it's known there
188 : * are no subqueries. There mustn't be outer-aggregate references either.
189 : *
190 : * (If you want something like this but able to deal with subqueries,
191 : * see rewriteManip.c's contain_aggs_of_level().)
192 : */
193 : bool
194 8781 : contain_agg_clause(Node *clause)
195 : {
196 8781 : return contain_agg_clause_walker(clause, NULL);
197 : }
198 :
199 : static bool
200 11302 : contain_agg_clause_walker(Node *node, void *context)
201 : {
202 11302 : if (node == NULL)
203 40 : return false;
204 11262 : if (IsA(node, Aggref))
205 : {
206 : Assert(((Aggref *) node)->agglevelsup == 0);
207 798 : return true; /* abort the tree traversal and return true */
208 : }
209 10464 : if (IsA(node, GroupingFunc))
210 : {
211 : Assert(((GroupingFunc *) node)->agglevelsup == 0);
212 25 : return true; /* abort the tree traversal and return true */
213 : }
214 : Assert(!IsA(node, SubLink));
215 10439 : return expression_tree_walker(node, contain_agg_clause_walker, context);
216 : }
217 :
218 : /*****************************************************************************
219 : * Window-function clause manipulation
220 : *****************************************************************************/
221 :
222 : /*
223 : * contain_window_function
224 : * Recursively search for WindowFunc nodes within a clause.
225 : *
226 : * Since window functions don't have level fields, but are hard-wired to
227 : * be associated with the current query level, this is just the same as
228 : * rewriteManip.c's function.
229 : */
230 : bool
231 7367 : contain_window_function(Node *clause)
232 : {
233 7367 : return contain_windowfuncs(clause);
234 : }
235 :
236 : /*
237 : * find_window_functions
238 : * Locate all the WindowFunc nodes in an expression tree, and organize
239 : * them by winref ID number.
240 : *
241 : * Caller must provide an upper bound on the winref IDs expected in the tree.
242 : */
243 : WindowFuncLists *
244 2237 : find_window_functions(Node *clause, Index maxWinRef)
245 : {
246 2237 : WindowFuncLists *lists = palloc_object(WindowFuncLists);
247 :
248 2237 : lists->numWindowFuncs = 0;
249 2237 : lists->maxWinRef = maxWinRef;
250 2237 : lists->windowFuncs = (List **) palloc0((maxWinRef + 1) * sizeof(List *));
251 2237 : (void) find_window_functions_walker(clause, lists);
252 2237 : return lists;
253 : }
254 :
255 : static bool
256 18795 : find_window_functions_walker(Node *node, WindowFuncLists *lists)
257 : {
258 18795 : if (node == NULL)
259 179 : return false;
260 18616 : if (IsA(node, WindowFunc))
261 : {
262 3092 : WindowFunc *wfunc = (WindowFunc *) node;
263 :
264 : /* winref is unsigned, so one-sided test is OK */
265 3092 : if (wfunc->winref > lists->maxWinRef)
266 0 : elog(ERROR, "WindowFunc contains out-of-range winref %u",
267 : wfunc->winref);
268 :
269 6184 : lists->windowFuncs[wfunc->winref] =
270 3092 : lappend(lists->windowFuncs[wfunc->winref], wfunc);
271 3092 : lists->numWindowFuncs++;
272 :
273 : /*
274 : * We assume that the parser checked that there are no window
275 : * functions in the arguments or filter clause. Hence, we need not
276 : * recurse into them. (If either the parser or the planner screws up
277 : * on this point, the executor will still catch it; see ExecInitExpr.)
278 : */
279 3092 : return false;
280 : }
281 : Assert(!IsA(node, SubLink));
282 15524 : return expression_tree_walker(node, find_window_functions_walker, lists);
283 : }
284 :
285 :
286 : /*****************************************************************************
287 : * Support for expressions returning sets
288 : *****************************************************************************/
289 :
290 : /*
291 : * expression_returns_set_rows
292 : * Estimate the number of rows returned by a set-returning expression.
293 : * The result is 1 if it's not a set-returning expression.
294 : *
295 : * We should only examine the top-level function or operator; it used to be
296 : * appropriate to recurse, but not anymore. (Even if there are more SRFs in
297 : * the function's inputs, their multipliers are accounted for separately.)
298 : *
299 : * Note: keep this in sync with expression_returns_set() in nodes/nodeFuncs.c.
300 : */
301 : double
302 329820 : expression_returns_set_rows(PlannerInfo *root, Node *clause)
303 : {
304 329820 : if (clause == NULL)
305 0 : return 1.0;
306 329820 : if (IsA(clause, FuncExpr))
307 : {
308 47507 : FuncExpr *expr = (FuncExpr *) clause;
309 :
310 47507 : if (expr->funcretset)
311 40951 : return clamp_row_est(get_function_rows(root, expr->funcid, clause));
312 : }
313 288869 : if (IsA(clause, OpExpr))
314 : {
315 2626 : OpExpr *expr = (OpExpr *) clause;
316 :
317 2626 : if (expr->opretset)
318 : {
319 5 : set_opfuncid(expr);
320 5 : return clamp_row_est(get_function_rows(root, expr->opfuncid, clause));
321 : }
322 : }
323 288864 : return 1.0;
324 : }
325 :
326 :
327 : /*****************************************************************************
328 : * Subplan clause manipulation
329 : *****************************************************************************/
330 :
331 : /*
332 : * contain_subplans
333 : * Recursively search for subplan nodes within a clause.
334 : *
335 : * If we see a SubLink node, we will return true. This is only possible if
336 : * the expression tree hasn't yet been transformed by subselect.c. We do not
337 : * know whether the node will produce a true subplan or just an initplan,
338 : * but we make the conservative assumption that it will be a subplan.
339 : *
340 : * Returns true if any subplan found.
341 : */
342 : bool
343 42001 : contain_subplans(Node *clause)
344 : {
345 42001 : return contain_subplans_walker(clause, NULL);
346 : }
347 :
348 : static bool
349 175242 : contain_subplans_walker(Node *node, void *context)
350 : {
351 175242 : if (node == NULL)
352 5038 : return false;
353 170204 : if (IsA(node, SubPlan) ||
354 170121 : IsA(node, AlternativeSubPlan) ||
355 170121 : IsA(node, SubLink))
356 253 : return true; /* abort the tree traversal and return true */
357 169951 : return expression_tree_walker(node, contain_subplans_walker, context);
358 : }
359 :
360 :
361 : /*****************************************************************************
362 : * Check clauses for mutable functions
363 : *****************************************************************************/
364 :
365 : /*
366 : * contain_mutable_functions
367 : * Recursively search for mutable functions within a clause.
368 : *
369 : * Returns true if any mutable function (or operator implemented by a
370 : * mutable function) is found. This test is needed so that we don't
371 : * mistakenly think that something like "WHERE random() < 0.5" can be treated
372 : * as a constant qualification.
373 : *
374 : * This will give the right answer only for clauses that have been put
375 : * through expression preprocessing. Callers outside the planner typically
376 : * should use contain_mutable_functions_after_planning() instead, for the
377 : * reasons given there.
378 : *
379 : * We will recursively look into Query nodes (i.e., SubLink sub-selects)
380 : * but not into SubPlans. See comments for contain_volatile_functions().
381 : */
382 : bool
383 120107 : contain_mutable_functions(Node *clause)
384 : {
385 120107 : return contain_mutable_functions_walker(clause, NULL);
386 : }
387 :
388 : static bool
389 90184 : contain_mutable_functions_checker(Oid func_id, void *context)
390 : {
391 90184 : return (func_volatile(func_id) != PROVOLATILE_IMMUTABLE);
392 : }
393 :
394 : static bool
395 324685 : contain_mutable_functions_walker(Node *node, void *context)
396 : {
397 324685 : if (node == NULL)
398 1870 : return false;
399 : /* Check for mutable functions in node itself */
400 322815 : if (check_functions_in_node(node, contain_mutable_functions_checker,
401 : context))
402 5950 : return true;
403 :
404 316865 : if (IsA(node, JsonConstructorExpr))
405 : {
406 176 : const JsonConstructorExpr *ctor = (JsonConstructorExpr *) node;
407 : ListCell *lc;
408 : bool is_jsonb;
409 :
410 176 : is_jsonb = ctor->returning->format->format_type == JS_FORMAT_JSONB;
411 :
412 : /*
413 : * Check argument_type => json[b] conversions specifically. We still
414 : * recurse to check 'args' below, but here we want to specifically
415 : * check whether or not the emitted clause would fail to be immutable
416 : * because of TimeZone, for example.
417 : */
418 296 : foreach(lc, ctor->args)
419 : {
420 264 : Oid typid = exprType(lfirst(lc));
421 :
422 528 : if (is_jsonb ?
423 144 : !to_jsonb_is_immutable(typid) :
424 120 : !to_json_is_immutable(typid))
425 144 : return true;
426 : }
427 :
428 : /* Check all subnodes */
429 : }
430 :
431 316721 : if (IsA(node, JsonExpr))
432 : {
433 188 : JsonExpr *jexpr = castNode(JsonExpr, node);
434 : Const *cnst;
435 :
436 188 : if (!IsA(jexpr->path_spec, Const))
437 0 : return true;
438 :
439 188 : cnst = castNode(Const, jexpr->path_spec);
440 :
441 : Assert(cnst->consttype == JSONPATHOID);
442 188 : if (cnst->constisnull)
443 0 : return false;
444 :
445 188 : if (jspIsMutable(DatumGetJsonPathP(cnst->constvalue),
446 : jexpr->passing_names, jexpr->passing_values))
447 108 : return true;
448 : }
449 :
450 316613 : if (IsA(node, SQLValueFunction))
451 : {
452 : /* all variants of SQLValueFunction are stable */
453 258 : return true;
454 : }
455 :
456 316355 : if (IsA(node, NextValueExpr))
457 : {
458 : /* NextValueExpr is volatile */
459 0 : return true;
460 : }
461 :
462 : /*
463 : * It should be safe to treat MinMaxExpr as immutable, because it will
464 : * depend on a non-cross-type btree comparison function, and those should
465 : * always be immutable. Treating XmlExpr as immutable is more dubious,
466 : * and treating CoerceToDomain as immutable is outright dangerous. But we
467 : * have done so historically, and changing this would probably cause more
468 : * problems than it would fix. In practice, if you have a non-immutable
469 : * domain constraint you are in for pain anyhow.
470 : */
471 :
472 : /* Recurse to check arguments */
473 316355 : if (IsA(node, Query))
474 : {
475 : /* Recurse into subselects */
476 0 : return query_tree_walker((Query *) node,
477 : contain_mutable_functions_walker,
478 : context, 0);
479 : }
480 316355 : return expression_tree_walker(node, contain_mutable_functions_walker,
481 : context);
482 : }
483 :
484 : /*
485 : * contain_mutable_functions_after_planning
486 : * Test whether given expression contains mutable functions.
487 : *
488 : * This is a wrapper for contain_mutable_functions() that is safe to use from
489 : * outside the planner. The difference is that it first runs the expression
490 : * through expression_planner(). There are two key reasons why we need that:
491 : *
492 : * First, function default arguments will get inserted, which may affect
493 : * volatility (consider "default now()").
494 : *
495 : * Second, inline-able functions will get inlined, which may allow us to
496 : * conclude that the function is really less volatile than it's marked.
497 : * As an example, polymorphic functions must be marked with the most volatile
498 : * behavior that they have for any input type, but once we inline the
499 : * function we may be able to conclude that it's not so volatile for the
500 : * particular input type we're dealing with.
501 : */
502 : bool
503 2549 : contain_mutable_functions_after_planning(Expr *expr)
504 : {
505 : /* We assume here that expression_planner() won't scribble on its input */
506 2549 : expr = expression_planner(expr);
507 :
508 : /* Now we can search for non-immutable functions */
509 2549 : return contain_mutable_functions((Node *) expr);
510 : }
511 :
512 :
513 : /*****************************************************************************
514 : * Check clauses for volatile functions
515 : *****************************************************************************/
516 :
517 : /*
518 : * contain_volatile_functions
519 : * Recursively search for volatile functions within a clause.
520 : *
521 : * Returns true if any volatile function (or operator implemented by a
522 : * volatile function) is found. This test prevents, for example,
523 : * invalid conversions of volatile expressions into indexscan quals.
524 : *
525 : * This will give the right answer only for clauses that have been put
526 : * through expression preprocessing. Callers outside the planner typically
527 : * should use contain_volatile_functions_after_planning() instead, for the
528 : * reasons given there.
529 : *
530 : * We will recursively look into Query nodes (i.e., SubLink sub-selects)
531 : * but not into SubPlans. This is a bit odd, but intentional. If we are
532 : * looking at a SubLink, we are probably deciding whether a query tree
533 : * transformation is safe, and a contained sub-select should affect that;
534 : * for example, duplicating a sub-select containing a volatile function
535 : * would be bad. However, once we've got to the stage of having SubPlans,
536 : * subsequent planning need not consider volatility within those, since
537 : * the executor won't change its evaluation rules for a SubPlan based on
538 : * volatility.
539 : *
540 : * For some node types, for example, RestrictInfo and PathTarget, we cache
541 : * whether we found any volatile functions or not and reuse that value in any
542 : * future checks for that node. All of the logic for determining if the
543 : * cached value should be set to VOLATILITY_NOVOLATILE or VOLATILITY_VOLATILE
544 : * belongs in this function. Any code which makes changes to these nodes
545 : * which could change the outcome this function must set the cached value back
546 : * to VOLATILITY_UNKNOWN. That allows this function to redetermine the
547 : * correct value during the next call, should we need to redetermine if the
548 : * node contains any volatile functions again in the future.
549 : */
550 : bool
551 2656731 : contain_volatile_functions(Node *clause)
552 : {
553 2656731 : return contain_volatile_functions_walker(clause, NULL);
554 : }
555 :
556 : static bool
557 755727 : contain_volatile_functions_checker(Oid func_id, void *context)
558 : {
559 755727 : return (func_volatile(func_id) == PROVOLATILE_VOLATILE);
560 : }
561 :
562 : static bool
563 6127034 : contain_volatile_functions_walker(Node *node, void *context)
564 : {
565 6127034 : if (node == NULL)
566 186037 : return false;
567 : /* Check for volatile functions in node itself */
568 5940997 : if (check_functions_in_node(node, contain_volatile_functions_checker,
569 : context))
570 1595 : return true;
571 :
572 5939402 : if (IsA(node, NextValueExpr))
573 : {
574 : /* NextValueExpr is volatile */
575 28 : return true;
576 : }
577 :
578 5939374 : if (IsA(node, RestrictInfo))
579 : {
580 1014870 : RestrictInfo *rinfo = (RestrictInfo *) node;
581 :
582 : /*
583 : * For RestrictInfo, check if we've checked the volatility of it
584 : * before. If so, we can just use the cached value and not bother
585 : * checking it again. Otherwise, check it and cache if whether we
586 : * found any volatile functions.
587 : */
588 1014870 : if (rinfo->has_volatile == VOLATILITY_NOVOLATILE)
589 611309 : return false;
590 403561 : else if (rinfo->has_volatile == VOLATILITY_VOLATILE)
591 54 : return true;
592 : else
593 : {
594 : bool hasvolatile;
595 :
596 403507 : hasvolatile = contain_volatile_functions_walker((Node *) rinfo->clause,
597 : context);
598 403507 : if (hasvolatile)
599 98 : rinfo->has_volatile = VOLATILITY_VOLATILE;
600 : else
601 403409 : rinfo->has_volatile = VOLATILITY_NOVOLATILE;
602 :
603 403507 : return hasvolatile;
604 : }
605 : }
606 :
607 4924504 : if (IsA(node, PathTarget))
608 : {
609 279546 : PathTarget *target = (PathTarget *) node;
610 :
611 : /*
612 : * We also do caching for PathTarget the same as we do above for
613 : * RestrictInfos.
614 : */
615 279546 : if (target->has_volatile_expr == VOLATILITY_NOVOLATILE)
616 231803 : return false;
617 47743 : else if (target->has_volatile_expr == VOLATILITY_VOLATILE)
618 0 : return true;
619 : else
620 : {
621 : bool hasvolatile;
622 :
623 47743 : hasvolatile = contain_volatile_functions_walker((Node *) target->exprs,
624 : context);
625 :
626 47743 : if (hasvolatile)
627 0 : target->has_volatile_expr = VOLATILITY_VOLATILE;
628 : else
629 47743 : target->has_volatile_expr = VOLATILITY_NOVOLATILE;
630 :
631 47743 : return hasvolatile;
632 : }
633 : }
634 :
635 : /*
636 : * See notes in contain_mutable_functions_walker about why we treat
637 : * MinMaxExpr, XmlExpr, and CoerceToDomain as immutable, while
638 : * SQLValueFunction is stable. Hence, none of them are of interest here.
639 : */
640 :
641 : /* Recurse to check arguments */
642 4644958 : if (IsA(node, Query))
643 : {
644 : /* Recurse into subselects */
645 5419 : return query_tree_walker((Query *) node,
646 : contain_volatile_functions_walker,
647 : context, 0);
648 : }
649 4639539 : return expression_tree_walker(node, contain_volatile_functions_walker,
650 : context);
651 : }
652 :
653 : /*
654 : * contain_volatile_functions_after_planning
655 : * Test whether given expression contains volatile functions.
656 : *
657 : * This is a wrapper for contain_volatile_functions() that is safe to use from
658 : * outside the planner. The difference is that it first runs the expression
659 : * through expression_planner(). There are two key reasons why we need that:
660 : *
661 : * First, function default arguments will get inserted, which may affect
662 : * volatility (consider "default random()").
663 : *
664 : * Second, inline-able functions will get inlined, which may allow us to
665 : * conclude that the function is really less volatile than it's marked.
666 : * As an example, polymorphic functions must be marked with the most volatile
667 : * behavior that they have for any input type, but once we inline the
668 : * function we may be able to conclude that it's not so volatile for the
669 : * particular input type we're dealing with.
670 : */
671 : bool
672 923 : contain_volatile_functions_after_planning(Expr *expr)
673 : {
674 : /* We assume here that expression_planner() won't scribble on its input */
675 923 : expr = expression_planner(expr);
676 :
677 : /* Now we can search for volatile functions */
678 915 : return contain_volatile_functions((Node *) expr);
679 : }
680 :
681 : /*
682 : * Special purpose version of contain_volatile_functions() for use in COPY:
683 : * ignore nextval(), but treat all other functions normally.
684 : */
685 : bool
686 159 : contain_volatile_functions_not_nextval(Node *clause)
687 : {
688 159 : return contain_volatile_functions_not_nextval_walker(clause, NULL);
689 : }
690 :
691 : static bool
692 41 : contain_volatile_functions_not_nextval_checker(Oid func_id, void *context)
693 : {
694 66 : return (func_id != F_NEXTVAL &&
695 25 : func_volatile(func_id) == PROVOLATILE_VOLATILE);
696 : }
697 :
698 : static bool
699 199 : contain_volatile_functions_not_nextval_walker(Node *node, void *context)
700 : {
701 199 : if (node == NULL)
702 0 : return false;
703 : /* Check for volatile functions in node itself */
704 199 : if (check_functions_in_node(node,
705 : contain_volatile_functions_not_nextval_checker,
706 : context))
707 4 : return true;
708 :
709 : /*
710 : * See notes in contain_mutable_functions_walker about why we treat
711 : * MinMaxExpr, XmlExpr, and CoerceToDomain as immutable, while
712 : * SQLValueFunction is stable. Hence, none of them are of interest here.
713 : * Also, since we're intentionally ignoring nextval(), presumably we
714 : * should ignore NextValueExpr.
715 : */
716 :
717 : /* Recurse to check arguments */
718 195 : if (IsA(node, Query))
719 : {
720 : /* Recurse into subselects */
721 0 : return query_tree_walker((Query *) node,
722 : contain_volatile_functions_not_nextval_walker,
723 : context, 0);
724 : }
725 195 : return expression_tree_walker(node,
726 : contain_volatile_functions_not_nextval_walker,
727 : context);
728 : }
729 :
730 :
731 : /*****************************************************************************
732 : * Check queries for parallel unsafe and/or restricted constructs
733 : *****************************************************************************/
734 :
735 : /*
736 : * max_parallel_hazard
737 : * Find the worst parallel-hazard level in the given query
738 : *
739 : * Returns the worst function hazard property (the earliest in this list:
740 : * PROPARALLEL_UNSAFE, PROPARALLEL_RESTRICTED, PROPARALLEL_SAFE) that can
741 : * be found in the given parsetree. We use this to find out whether the query
742 : * can be parallelized at all. The caller will also save the result in
743 : * PlannerGlobal so as to short-circuit checks of portions of the querytree
744 : * later, in the common case where everything is SAFE.
745 : */
746 : char
747 258465 : max_parallel_hazard(Query *parse)
748 : {
749 : max_parallel_hazard_context context;
750 :
751 258465 : context.max_hazard = PROPARALLEL_SAFE;
752 258465 : context.max_interesting = PROPARALLEL_UNSAFE;
753 258465 : context.safe_param_ids = NIL;
754 258465 : (void) max_parallel_hazard_walker((Node *) parse, &context);
755 258465 : return context.max_hazard;
756 : }
757 :
758 : /*
759 : * is_parallel_safe
760 : * Detect whether the given expr contains only parallel-safe functions
761 : *
762 : * root->glob->maxParallelHazard must previously have been set to the
763 : * result of max_parallel_hazard() on the whole query.
764 : */
765 : bool
766 1898150 : is_parallel_safe(PlannerInfo *root, Node *node)
767 : {
768 : max_parallel_hazard_context context;
769 : PlannerInfo *proot;
770 : ListCell *l;
771 :
772 : /*
773 : * Even if the original querytree contained nothing unsafe, we need to
774 : * search the expression if we have generated any PARAM_EXEC Params while
775 : * planning, because those are parallel-restricted and there might be one
776 : * in this expression. But otherwise we don't need to look.
777 : */
778 1898150 : if (root->glob->maxParallelHazard == PROPARALLEL_SAFE &&
779 1150658 : root->glob->paramExecTypes == NIL)
780 1123294 : return true;
781 : /* Else use max_parallel_hazard's search logic, but stop on RESTRICTED */
782 774856 : context.max_hazard = PROPARALLEL_SAFE;
783 774856 : context.max_interesting = PROPARALLEL_RESTRICTED;
784 774856 : context.safe_param_ids = NIL;
785 :
786 : /*
787 : * The params that refer to the same or parent query level are considered
788 : * parallel-safe. The idea is that we compute such params at Gather or
789 : * Gather Merge node and pass their value to workers.
790 : */
791 1892183 : for (proot = root; proot != NULL; proot = proot->parent_root)
792 : {
793 1171120 : foreach(l, proot->init_plans)
794 : {
795 53793 : SubPlan *initsubplan = (SubPlan *) lfirst(l);
796 :
797 53793 : context.safe_param_ids = list_concat(context.safe_param_ids,
798 53793 : initsubplan->setParam);
799 : }
800 : }
801 :
802 774856 : return !max_parallel_hazard_walker(node, &context);
803 : }
804 :
805 : /* core logic for all parallel-hazard checks */
806 : static bool
807 1297101 : max_parallel_hazard_test(char proparallel, max_parallel_hazard_context *context)
808 : {
809 1297101 : switch (proparallel)
810 : {
811 1089102 : case PROPARALLEL_SAFE:
812 : /* nothing to see here, move along */
813 1089102 : break;
814 156601 : case PROPARALLEL_RESTRICTED:
815 : /* increase max_hazard to RESTRICTED */
816 : Assert(context->max_hazard != PROPARALLEL_UNSAFE);
817 156601 : context->max_hazard = proparallel;
818 : /* done if we are not expecting any unsafe functions */
819 156601 : if (context->max_interesting == proparallel)
820 77533 : return true;
821 79068 : break;
822 51398 : case PROPARALLEL_UNSAFE:
823 51398 : context->max_hazard = proparallel;
824 : /* we're always done at the first unsafe construct */
825 51398 : return true;
826 0 : default:
827 0 : elog(ERROR, "unrecognized proparallel value \"%c\"", proparallel);
828 : break;
829 : }
830 1168170 : return false;
831 : }
832 :
833 : /* check_functions_in_node callback */
834 : static bool
835 1182448 : max_parallel_hazard_checker(Oid func_id, void *context)
836 : {
837 1182448 : return max_parallel_hazard_test(func_parallel(func_id),
838 : (max_parallel_hazard_context *) context);
839 : }
840 :
841 : static bool
842 16939800 : max_parallel_hazard_walker(Node *node, max_parallel_hazard_context *context)
843 : {
844 16939800 : if (node == NULL)
845 4719545 : return false;
846 :
847 : /* Check for hazardous functions in node itself */
848 12220255 : if (check_functions_in_node(node, max_parallel_hazard_checker,
849 : context))
850 67540 : return true;
851 :
852 : /*
853 : * It should be OK to treat MinMaxExpr as parallel-safe, since btree
854 : * opclass support functions are generally parallel-safe. XmlExpr is a
855 : * bit more dubious but we can probably get away with it. We err on the
856 : * side of caution by treating CoerceToDomain as parallel-restricted.
857 : * (Note: in principle that's wrong because a domain constraint could
858 : * contain a parallel-unsafe function; but useful constraints probably
859 : * never would have such, and assuming they do would cripple use of
860 : * parallel query in the presence of domain types.) SQLValueFunction
861 : * should be safe in all cases. NextValueExpr is parallel-unsafe.
862 : */
863 12152715 : if (IsA(node, CoerceToDomain))
864 : {
865 15796 : if (max_parallel_hazard_test(PROPARALLEL_RESTRICTED, context))
866 4336 : return true;
867 : }
868 :
869 12136919 : else if (IsA(node, NextValueExpr))
870 : {
871 320 : if (max_parallel_hazard_test(PROPARALLEL_UNSAFE, context))
872 320 : return true;
873 : }
874 :
875 : /*
876 : * Treat window functions as parallel-restricted because we aren't sure
877 : * whether the input row ordering is fully deterministic, and the output
878 : * of window functions might vary across workers if not. (In some cases,
879 : * like where the window frame orders by a primary key, we could relax
880 : * this restriction. But it doesn't currently seem worth expending extra
881 : * effort to do so.)
882 : */
883 12136599 : else if (IsA(node, WindowFunc))
884 : {
885 5186 : if (max_parallel_hazard_test(PROPARALLEL_RESTRICTED, context))
886 2298 : return true;
887 : }
888 :
889 : /*
890 : * As a notational convenience for callers, look through RestrictInfo.
891 : */
892 12131413 : else if (IsA(node, RestrictInfo))
893 : {
894 199685 : RestrictInfo *rinfo = (RestrictInfo *) node;
895 :
896 199685 : return max_parallel_hazard_walker((Node *) rinfo->clause, context);
897 : }
898 :
899 : /*
900 : * Really we should not see SubLink during a max_interesting == restricted
901 : * scan, but if we do, return true.
902 : */
903 11931728 : else if (IsA(node, SubLink))
904 : {
905 34803 : if (max_parallel_hazard_test(PROPARALLEL_RESTRICTED, context))
906 0 : return true;
907 : }
908 :
909 : /*
910 : * Only parallel-safe SubPlans can be sent to workers. Within the
911 : * testexpr of the SubPlan, Params representing the output columns of the
912 : * subplan can be treated as parallel-safe, so temporarily add their IDs
913 : * to the safe_param_ids list while examining the testexpr.
914 : */
915 11896925 : else if (IsA(node, SubPlan))
916 : {
917 24821 : SubPlan *subplan = (SubPlan *) node;
918 : List *save_safe_param_ids;
919 :
920 49377 : if (!subplan->parallel_safe &&
921 24556 : max_parallel_hazard_test(PROPARALLEL_RESTRICTED, context))
922 24556 : return true;
923 265 : save_safe_param_ids = context->safe_param_ids;
924 530 : context->safe_param_ids = list_concat_copy(context->safe_param_ids,
925 265 : subplan->paramIds);
926 265 : if (max_parallel_hazard_walker(subplan->testexpr, context))
927 5 : return true; /* no need to restore safe_param_ids */
928 260 : list_free(context->safe_param_ids);
929 260 : context->safe_param_ids = save_safe_param_ids;
930 : /* we must also check args, but no special Param treatment there */
931 260 : if (max_parallel_hazard_walker((Node *) subplan->args, context))
932 0 : return true;
933 : /* don't want to recurse normally, so we're done */
934 260 : return false;
935 : }
936 :
937 : /*
938 : * We can't pass Params to workers at the moment either, so they are also
939 : * parallel-restricted, unless they are PARAM_EXTERN Params or are
940 : * PARAM_EXEC Params listed in safe_param_ids, meaning they could be
941 : * either generated within workers or can be computed by the leader and
942 : * then their value can be passed to workers.
943 : */
944 11872104 : else if (IsA(node, Param))
945 : {
946 84616 : Param *param = (Param *) node;
947 :
948 84616 : if (param->paramkind == PARAM_EXTERN)
949 42609 : return false;
950 :
951 42007 : if (param->paramkind != PARAM_EXEC ||
952 37843 : !list_member_int(context->safe_param_ids, param->paramid))
953 : {
954 33992 : if (max_parallel_hazard_test(PROPARALLEL_RESTRICTED, context))
955 29881 : return true;
956 : }
957 12126 : return false; /* nothing to recurse to */
958 : }
959 :
960 : /*
961 : * When we're first invoked on a completely unplanned tree, we must
962 : * recurse into subqueries so to as to locate parallel-unsafe constructs
963 : * anywhere in the tree.
964 : */
965 11787488 : else if (IsA(node, Query))
966 : {
967 344659 : Query *query = (Query *) node;
968 :
969 : /* SELECT FOR UPDATE/SHARE must be treated as unsafe */
970 344659 : if (query->rowMarks != NULL)
971 : {
972 3849 : context->max_hazard = PROPARALLEL_UNSAFE;
973 3849 : return true;
974 : }
975 :
976 : /* Recurse into subselects */
977 340810 : return query_tree_walker(query,
978 : max_parallel_hazard_walker,
979 : context, 0);
980 : }
981 :
982 : /* Recurse to check arguments */
983 11491980 : return expression_tree_walker(node,
984 : max_parallel_hazard_walker,
985 : context);
986 : }
987 :
988 :
989 : /*****************************************************************************
990 : * Check clauses for nonstrict functions
991 : *****************************************************************************/
992 :
993 : /*
994 : * contain_nonstrict_functions
995 : * Recursively search for nonstrict functions within a clause.
996 : *
997 : * Returns true if any nonstrict construct is found --- ie, anything that
998 : * could produce non-NULL output with a NULL input.
999 : *
1000 : * The idea here is that the caller has verified that the expression contains
1001 : * one or more Var or Param nodes (as appropriate for the caller's need), and
1002 : * now wishes to prove that the expression result will be NULL if any of these
1003 : * inputs is NULL. If we return false, then the proof succeeded.
1004 : */
1005 : bool
1006 1902 : contain_nonstrict_functions(Node *clause)
1007 : {
1008 1902 : return contain_nonstrict_functions_walker(clause, NULL);
1009 : }
1010 :
1011 : static bool
1012 1977 : contain_nonstrict_functions_checker(Oid func_id, void *context)
1013 : {
1014 1977 : return !func_strict(func_id);
1015 : }
1016 :
1017 : static bool
1018 6675 : contain_nonstrict_functions_walker(Node *node, void *context)
1019 : {
1020 6675 : if (node == NULL)
1021 0 : return false;
1022 6675 : if (IsA(node, Aggref))
1023 : {
1024 : /* an aggregate could return non-null with null input */
1025 0 : return true;
1026 : }
1027 6675 : if (IsA(node, GroupingFunc))
1028 : {
1029 : /*
1030 : * A GroupingFunc doesn't evaluate its arguments, and therefore must
1031 : * be treated as nonstrict.
1032 : */
1033 0 : return true;
1034 : }
1035 6675 : if (IsA(node, WindowFunc))
1036 : {
1037 : /* a window function could return non-null with null input */
1038 0 : return true;
1039 : }
1040 6675 : if (IsA(node, SubscriptingRef))
1041 : {
1042 0 : SubscriptingRef *sbsref = (SubscriptingRef *) node;
1043 : const SubscriptRoutines *sbsroutines;
1044 :
1045 : /* Subscripting assignment is always presumed nonstrict */
1046 0 : if (sbsref->refassgnexpr != NULL)
1047 0 : return true;
1048 : /* Otherwise we must look up the subscripting support methods */
1049 0 : sbsroutines = getSubscriptingRoutines(sbsref->refcontainertype, NULL);
1050 0 : if (!(sbsroutines && sbsroutines->fetch_strict))
1051 0 : return true;
1052 : /* else fall through to check args */
1053 : }
1054 6675 : if (IsA(node, DistinctExpr))
1055 : {
1056 : /* IS DISTINCT FROM is inherently non-strict */
1057 0 : return true;
1058 : }
1059 6675 : if (IsA(node, NullIfExpr))
1060 : {
1061 : /* NULLIF is inherently non-strict */
1062 0 : return true;
1063 : }
1064 6675 : if (IsA(node, BoolExpr))
1065 : {
1066 15 : BoolExpr *expr = (BoolExpr *) node;
1067 :
1068 15 : switch (expr->boolop)
1069 : {
1070 15 : case AND_EXPR:
1071 : case OR_EXPR:
1072 : /* AND, OR are inherently non-strict */
1073 15 : return true;
1074 0 : default:
1075 0 : break;
1076 : }
1077 : }
1078 6660 : if (IsA(node, SubLink))
1079 : {
1080 : /* In some cases a sublink might be strict, but in general not */
1081 10 : return true;
1082 : }
1083 6650 : if (IsA(node, SubPlan))
1084 0 : return true;
1085 6650 : if (IsA(node, AlternativeSubPlan))
1086 0 : return true;
1087 6650 : if (IsA(node, FieldStore))
1088 0 : return true;
1089 6650 : if (IsA(node, CoerceViaIO))
1090 : {
1091 : /*
1092 : * CoerceViaIO is strict regardless of whether the I/O functions are,
1093 : * so just go look at its argument; asking check_functions_in_node is
1094 : * useless expense and could deliver the wrong answer.
1095 : */
1096 874 : return contain_nonstrict_functions_walker((Node *) ((CoerceViaIO *) node)->arg,
1097 : context);
1098 : }
1099 5776 : if (IsA(node, ArrayCoerceExpr))
1100 : {
1101 : /*
1102 : * ArrayCoerceExpr is strict at the array level, regardless of what
1103 : * the per-element expression is; so we should ignore elemexpr and
1104 : * recurse only into the arg.
1105 : */
1106 0 : return contain_nonstrict_functions_walker((Node *) ((ArrayCoerceExpr *) node)->arg,
1107 : context);
1108 : }
1109 5776 : if (IsA(node, CaseExpr))
1110 52 : return true;
1111 5724 : if (IsA(node, ArrayExpr))
1112 0 : return true;
1113 5724 : if (IsA(node, RowExpr))
1114 2 : return true;
1115 5722 : if (IsA(node, RowCompareExpr))
1116 0 : return true;
1117 5722 : if (IsA(node, CoalesceExpr))
1118 211 : return true;
1119 5511 : if (IsA(node, MinMaxExpr))
1120 50 : return true;
1121 5461 : if (IsA(node, XmlExpr))
1122 0 : return true;
1123 5461 : if (IsA(node, NullTest))
1124 20 : return true;
1125 5441 : if (IsA(node, BooleanTest))
1126 0 : return true;
1127 5441 : if (IsA(node, JsonConstructorExpr))
1128 10 : return true;
1129 :
1130 : /* Check other function-containing nodes */
1131 5431 : if (check_functions_in_node(node, contain_nonstrict_functions_checker,
1132 : context))
1133 0 : return true;
1134 :
1135 5431 : return expression_tree_walker(node, contain_nonstrict_functions_walker,
1136 : context);
1137 : }
1138 :
1139 : /*****************************************************************************
1140 : * Check clauses for Params
1141 : *****************************************************************************/
1142 :
1143 : /*
1144 : * contain_exec_param
1145 : * Recursively search for PARAM_EXEC Params within a clause.
1146 : *
1147 : * Returns true if the clause contains any PARAM_EXEC Param with a paramid
1148 : * appearing in the given list of Param IDs. Does not descend into
1149 : * subqueries!
1150 : */
1151 : bool
1152 2452 : contain_exec_param(Node *clause, List *param_ids)
1153 : {
1154 2452 : return contain_exec_param_walker(clause, param_ids);
1155 : }
1156 :
1157 : static bool
1158 2692 : contain_exec_param_walker(Node *node, List *param_ids)
1159 : {
1160 2692 : if (node == NULL)
1161 30 : return false;
1162 2662 : if (IsA(node, Param))
1163 : {
1164 10 : Param *p = (Param *) node;
1165 :
1166 20 : if (p->paramkind == PARAM_EXEC &&
1167 10 : list_member_int(param_ids, p->paramid))
1168 10 : return true;
1169 : }
1170 2652 : return expression_tree_walker(node, contain_exec_param_walker, param_ids);
1171 : }
1172 :
1173 : /*****************************************************************************
1174 : * Check clauses for context-dependent nodes
1175 : *****************************************************************************/
1176 :
1177 : /*
1178 : * contain_context_dependent_node
1179 : * Recursively search for context-dependent nodes within a clause.
1180 : *
1181 : * CaseTestExpr nodes must appear directly within the corresponding CaseExpr,
1182 : * not nested within another one, or they'll see the wrong test value. If one
1183 : * appears "bare" in the arguments of a SQL function, then we can't inline the
1184 : * SQL function for fear of creating such a situation. The same applies for
1185 : * CaseTestExpr used within the elemexpr of an ArrayCoerceExpr.
1186 : *
1187 : * CoerceToDomainValue would have the same issue if domain CHECK expressions
1188 : * could get inlined into larger expressions, but presently that's impossible.
1189 : * Still, it might be allowed in future, or other node types with similar
1190 : * issues might get invented. So give this function a generic name, and set
1191 : * up the recursion state to allow multiple flag bits.
1192 : */
1193 : static bool
1194 2546 : contain_context_dependent_node(Node *clause)
1195 : {
1196 2546 : int flags = 0;
1197 :
1198 2546 : return contain_context_dependent_node_walker(clause, &flags);
1199 : }
1200 :
1201 : #define CCDN_CASETESTEXPR_OK 0x0001 /* CaseTestExpr okay here? */
1202 :
1203 : static bool
1204 7820 : contain_context_dependent_node_walker(Node *node, int *flags)
1205 : {
1206 7820 : if (node == NULL)
1207 136 : return false;
1208 7684 : if (IsA(node, CaseTestExpr))
1209 5 : return !(*flags & CCDN_CASETESTEXPR_OK);
1210 7679 : else if (IsA(node, CaseExpr))
1211 : {
1212 0 : CaseExpr *caseexpr = (CaseExpr *) node;
1213 :
1214 : /*
1215 : * If this CASE doesn't have a test expression, then it doesn't create
1216 : * a context in which CaseTestExprs should appear, so just fall
1217 : * through and treat it as a generic expression node.
1218 : */
1219 0 : if (caseexpr->arg)
1220 : {
1221 0 : int save_flags = *flags;
1222 : bool res;
1223 :
1224 : /*
1225 : * Note: in principle, we could distinguish the various sub-parts
1226 : * of a CASE construct and set the flag bit only for some of them,
1227 : * since we are only expecting CaseTestExprs to appear in the
1228 : * "expr" subtree of the CaseWhen nodes. But it doesn't really
1229 : * seem worth any extra code. If there are any bare CaseTestExprs
1230 : * elsewhere in the CASE, something's wrong already.
1231 : */
1232 0 : *flags |= CCDN_CASETESTEXPR_OK;
1233 0 : res = expression_tree_walker(node,
1234 : contain_context_dependent_node_walker,
1235 : flags);
1236 0 : *flags = save_flags;
1237 0 : return res;
1238 : }
1239 : }
1240 7679 : else if (IsA(node, ArrayCoerceExpr))
1241 : {
1242 0 : ArrayCoerceExpr *ac = (ArrayCoerceExpr *) node;
1243 : int save_flags;
1244 : bool res;
1245 :
1246 : /* Check the array expression */
1247 0 : if (contain_context_dependent_node_walker((Node *) ac->arg, flags))
1248 0 : return true;
1249 :
1250 : /* Check the elemexpr, which is allowed to contain CaseTestExpr */
1251 0 : save_flags = *flags;
1252 0 : *flags |= CCDN_CASETESTEXPR_OK;
1253 0 : res = contain_context_dependent_node_walker((Node *) ac->elemexpr,
1254 : flags);
1255 0 : *flags = save_flags;
1256 0 : return res;
1257 : }
1258 7679 : return expression_tree_walker(node, contain_context_dependent_node_walker,
1259 : flags);
1260 : }
1261 :
1262 : /*****************************************************************************
1263 : * Check clauses for Vars passed to non-leakproof functions
1264 : *****************************************************************************/
1265 :
1266 : /*
1267 : * contain_leaked_vars
1268 : * Recursively scan a clause to discover whether it contains any Var
1269 : * nodes (of the current query level) that are passed as arguments to
1270 : * leaky functions.
1271 : *
1272 : * Returns true if the clause contains any non-leakproof functions that are
1273 : * passed Var nodes of the current query level, and which might therefore leak
1274 : * data. Such clauses must be applied after any lower-level security barrier
1275 : * clauses.
1276 : */
1277 : bool
1278 6761 : contain_leaked_vars(Node *clause)
1279 : {
1280 6761 : return contain_leaked_vars_walker(clause, NULL);
1281 : }
1282 :
1283 : static bool
1284 6646 : contain_leaked_vars_checker(Oid func_id, void *context)
1285 : {
1286 6646 : return !get_func_leakproof(func_id);
1287 : }
1288 :
1289 : static bool
1290 15369 : contain_leaked_vars_walker(Node *node, void *context)
1291 : {
1292 15369 : if (node == NULL)
1293 0 : return false;
1294 :
1295 15369 : switch (nodeTag(node))
1296 : {
1297 8663 : case T_Var:
1298 : case T_Const:
1299 : case T_Param:
1300 : case T_ArrayExpr:
1301 : case T_FieldSelect:
1302 : case T_FieldStore:
1303 : case T_NamedArgExpr:
1304 : case T_BoolExpr:
1305 : case T_RelabelType:
1306 : case T_CollateExpr:
1307 : case T_CaseExpr:
1308 : case T_CaseTestExpr:
1309 : case T_RowExpr:
1310 : case T_SQLValueFunction:
1311 : case T_NullTest:
1312 : case T_BooleanTest:
1313 : case T_NextValueExpr:
1314 : case T_ReturningExpr:
1315 : case T_List:
1316 :
1317 : /*
1318 : * We know these node types don't contain function calls; but
1319 : * something further down in the node tree might.
1320 : */
1321 8663 : break;
1322 :
1323 6646 : case T_FuncExpr:
1324 : case T_OpExpr:
1325 : case T_DistinctExpr:
1326 : case T_NullIfExpr:
1327 : case T_ScalarArrayOpExpr:
1328 : case T_CoerceViaIO:
1329 : case T_ArrayCoerceExpr:
1330 :
1331 : /*
1332 : * If node contains a leaky function call, and there's any Var
1333 : * underneath it, reject.
1334 : */
1335 6646 : if (check_functions_in_node(node, contain_leaked_vars_checker,
1336 2390 : context) &&
1337 2390 : contain_var_clause(node))
1338 2346 : return true;
1339 4300 : break;
1340 :
1341 0 : case T_SubscriptingRef:
1342 : {
1343 0 : SubscriptingRef *sbsref = (SubscriptingRef *) node;
1344 : const SubscriptRoutines *sbsroutines;
1345 :
1346 : /* Consult the subscripting support method info */
1347 0 : sbsroutines = getSubscriptingRoutines(sbsref->refcontainertype,
1348 : NULL);
1349 0 : if (!sbsroutines ||
1350 0 : !(sbsref->refassgnexpr != NULL ?
1351 0 : sbsroutines->store_leakproof :
1352 0 : sbsroutines->fetch_leakproof))
1353 : {
1354 : /* Node is leaky, so reject if it contains Vars */
1355 0 : if (contain_var_clause(node))
1356 0 : return true;
1357 : }
1358 : }
1359 0 : break;
1360 :
1361 0 : case T_RowCompareExpr:
1362 : {
1363 : /*
1364 : * It's worth special-casing this because a leaky comparison
1365 : * function only compromises one pair of row elements, which
1366 : * might not contain Vars while others do.
1367 : */
1368 0 : RowCompareExpr *rcexpr = (RowCompareExpr *) node;
1369 : ListCell *opid;
1370 : ListCell *larg;
1371 : ListCell *rarg;
1372 :
1373 0 : forthree(opid, rcexpr->opnos,
1374 : larg, rcexpr->largs,
1375 : rarg, rcexpr->rargs)
1376 : {
1377 0 : Oid funcid = get_opcode(lfirst_oid(opid));
1378 :
1379 0 : if (!get_func_leakproof(funcid) &&
1380 0 : (contain_var_clause((Node *) lfirst(larg)) ||
1381 0 : contain_var_clause((Node *) lfirst(rarg))))
1382 0 : return true;
1383 : }
1384 : }
1385 0 : break;
1386 :
1387 0 : case T_MinMaxExpr:
1388 : {
1389 : /*
1390 : * MinMaxExpr is leakproof if the comparison function it calls
1391 : * is leakproof.
1392 : */
1393 0 : MinMaxExpr *minmaxexpr = (MinMaxExpr *) node;
1394 : TypeCacheEntry *typentry;
1395 : bool leakproof;
1396 :
1397 : /* Look up the btree comparison function for the datatype */
1398 0 : typentry = lookup_type_cache(minmaxexpr->minmaxtype,
1399 : TYPECACHE_CMP_PROC);
1400 0 : if (OidIsValid(typentry->cmp_proc))
1401 0 : leakproof = get_func_leakproof(typentry->cmp_proc);
1402 : else
1403 : {
1404 : /*
1405 : * The executor will throw an error, but here we just
1406 : * treat the missing function as leaky.
1407 : */
1408 0 : leakproof = false;
1409 : }
1410 :
1411 0 : if (!leakproof &&
1412 0 : contain_var_clause((Node *) minmaxexpr->args))
1413 0 : return true;
1414 : }
1415 0 : break;
1416 :
1417 35 : case T_CurrentOfExpr:
1418 :
1419 : /*
1420 : * WHERE CURRENT OF doesn't contain leaky function calls.
1421 : * Moreover, it is essential that this is considered non-leaky,
1422 : * since the planner must always generate a TID scan when CURRENT
1423 : * OF is present -- cf. cost_tidscan.
1424 : */
1425 35 : return false;
1426 :
1427 25 : default:
1428 :
1429 : /*
1430 : * If we don't recognize the node tag, assume it might be leaky.
1431 : * This prevents an unexpected security hole if someone adds a new
1432 : * node type that can call a function.
1433 : */
1434 25 : return true;
1435 : }
1436 12963 : return expression_tree_walker(node, contain_leaked_vars_walker,
1437 : context);
1438 : }
1439 :
1440 : /*****************************************************************************
1441 : * Nullability analysis
1442 : *****************************************************************************/
1443 :
1444 : /*
1445 : * find_nonnullable_rels
1446 : * Determine which base rels are forced nonnullable by given clause.
1447 : *
1448 : * Returns the set of all Relids that are referenced in the clause in such
1449 : * a way that the clause cannot possibly return TRUE if any of these Relids
1450 : * is an all-NULL row. (It is OK to err on the side of conservatism; hence
1451 : * the analysis here is simplistic.)
1452 : *
1453 : * The semantics here are subtly different from contain_nonstrict_functions:
1454 : * that function is concerned with NULL results from arbitrary expressions,
1455 : * but here we assume that the input is a Boolean expression, and wish to
1456 : * see if NULL inputs will provably cause a FALSE-or-NULL result. We expect
1457 : * the expression to have been AND/OR flattened and converted to implicit-AND
1458 : * format.
1459 : *
1460 : * Note: this function is largely duplicative of find_nonnullable_vars().
1461 : * The reason not to simplify this function into a thin wrapper around
1462 : * find_nonnullable_vars() is that the tested conditions really are different:
1463 : * a clause like "t1.v1 IS NOT NULL OR t1.v2 IS NOT NULL" does not prove
1464 : * that either v1 or v2 can't be NULL, but it does prove that the t1 row
1465 : * as a whole can't be all-NULL. Also, the behavior for PHVs is different.
1466 : *
1467 : * top_level is true while scanning top-level AND/OR structure; here, showing
1468 : * the result is either FALSE or NULL is good enough. top_level is false when
1469 : * we have descended below a NOT or a strict function: now we must be able to
1470 : * prove that the subexpression goes to NULL.
1471 : *
1472 : * We don't use expression_tree_walker here because we don't want to descend
1473 : * through very many kinds of nodes; only the ones we can be sure are strict.
1474 : */
1475 : Relids
1476 82237 : find_nonnullable_rels(Node *clause)
1477 : {
1478 82237 : return find_nonnullable_rels_walker(clause, true);
1479 : }
1480 :
1481 : static Relids
1482 545294 : find_nonnullable_rels_walker(Node *node, bool top_level)
1483 : {
1484 545294 : Relids result = NULL;
1485 : ListCell *l;
1486 :
1487 545294 : if (node == NULL)
1488 5163 : return NULL;
1489 540131 : if (IsA(node, Var))
1490 : {
1491 173919 : Var *var = (Var *) node;
1492 :
1493 173919 : if (var->varlevelsup == 0)
1494 173919 : result = bms_make_singleton(var->varno);
1495 : }
1496 366212 : else if (IsA(node, List))
1497 : {
1498 : /*
1499 : * At top level, we are examining an implicit-AND list: if any of the
1500 : * arms produces FALSE-or-NULL then the result is FALSE-or-NULL. If
1501 : * not at top level, we are examining the arguments of a strict
1502 : * function: if any of them produce NULL then the result of the
1503 : * function must be NULL. So in both cases, the set of nonnullable
1504 : * rels is the union of those found in the arms, and we pass down the
1505 : * top_level flag unmodified.
1506 : */
1507 525622 : foreach(l, (List *) node)
1508 : {
1509 334145 : result = bms_join(result,
1510 334145 : find_nonnullable_rels_walker(lfirst(l),
1511 : top_level));
1512 : }
1513 : }
1514 174735 : else if (IsA(node, FuncExpr))
1515 : {
1516 6759 : FuncExpr *expr = (FuncExpr *) node;
1517 :
1518 6759 : if (func_strict(expr->funcid))
1519 6605 : result = find_nonnullable_rels_walker((Node *) expr->args, false);
1520 : }
1521 167976 : else if (IsA(node, OpExpr))
1522 : {
1523 97819 : OpExpr *expr = (OpExpr *) node;
1524 :
1525 97819 : set_opfuncid(expr);
1526 97819 : if (func_strict(expr->opfuncid))
1527 97819 : result = find_nonnullable_rels_walker((Node *) expr->args, false);
1528 : }
1529 70157 : else if (IsA(node, ScalarArrayOpExpr))
1530 : {
1531 6378 : ScalarArrayOpExpr *expr = (ScalarArrayOpExpr *) node;
1532 :
1533 6378 : if (is_strict_saop(expr, true))
1534 6378 : result = find_nonnullable_rels_walker((Node *) expr->args, false);
1535 : }
1536 63779 : else if (IsA(node, BoolExpr))
1537 : {
1538 7346 : BoolExpr *expr = (BoolExpr *) node;
1539 :
1540 7346 : switch (expr->boolop)
1541 : {
1542 329 : case AND_EXPR:
1543 : /* At top level we can just recurse (to the List case) */
1544 329 : if (top_level)
1545 : {
1546 329 : result = find_nonnullable_rels_walker((Node *) expr->args,
1547 : top_level);
1548 329 : break;
1549 : }
1550 :
1551 : /*
1552 : * Below top level, even if one arm produces NULL, the result
1553 : * could be FALSE (hence not NULL). However, if *all* the
1554 : * arms produce NULL then the result is NULL, so we can take
1555 : * the intersection of the sets of nonnullable rels, just as
1556 : * for OR. Fall through to share code.
1557 : */
1558 : pg_fallthrough;
1559 : case OR_EXPR:
1560 :
1561 : /*
1562 : * OR is strict if all of its arms are, so we can take the
1563 : * intersection of the sets of nonnullable rels for each arm.
1564 : * This works for both values of top_level.
1565 : */
1566 9250 : foreach(l, expr->args)
1567 : {
1568 : Relids subresult;
1569 :
1570 7451 : subresult = find_nonnullable_rels_walker(lfirst(l),
1571 : top_level);
1572 7451 : if (result == NULL) /* first subresult? */
1573 3745 : result = subresult;
1574 : else
1575 3706 : result = bms_int_members(result, subresult);
1576 :
1577 : /*
1578 : * If the intersection is empty, we can stop looking. This
1579 : * also justifies the test for first-subresult above.
1580 : */
1581 7451 : if (bms_is_empty(result))
1582 1946 : break;
1583 : }
1584 3745 : break;
1585 3272 : case NOT_EXPR:
1586 : /* NOT will return null if its arg is null */
1587 3272 : result = find_nonnullable_rels_walker((Node *) expr->args,
1588 : false);
1589 3272 : break;
1590 0 : default:
1591 0 : elog(ERROR, "unrecognized boolop: %d", (int) expr->boolop);
1592 : break;
1593 : }
1594 : }
1595 56433 : else if (IsA(node, RelabelType))
1596 : {
1597 3480 : RelabelType *expr = (RelabelType *) node;
1598 :
1599 3480 : result = find_nonnullable_rels_walker((Node *) expr->arg, top_level);
1600 : }
1601 52953 : else if (IsA(node, CoerceViaIO))
1602 : {
1603 : /* not clear this is useful, but it can't hurt */
1604 177 : CoerceViaIO *expr = (CoerceViaIO *) node;
1605 :
1606 177 : result = find_nonnullable_rels_walker((Node *) expr->arg, top_level);
1607 : }
1608 52776 : else if (IsA(node, ArrayCoerceExpr))
1609 : {
1610 : /* ArrayCoerceExpr is strict at the array level; ignore elemexpr */
1611 0 : ArrayCoerceExpr *expr = (ArrayCoerceExpr *) node;
1612 :
1613 0 : result = find_nonnullable_rels_walker((Node *) expr->arg, top_level);
1614 : }
1615 52776 : else if (IsA(node, ConvertRowtypeExpr))
1616 : {
1617 : /* not clear this is useful, but it can't hurt */
1618 0 : ConvertRowtypeExpr *expr = (ConvertRowtypeExpr *) node;
1619 :
1620 0 : result = find_nonnullable_rels_walker((Node *) expr->arg, top_level);
1621 : }
1622 52776 : else if (IsA(node, CollateExpr))
1623 : {
1624 0 : CollateExpr *expr = (CollateExpr *) node;
1625 :
1626 0 : result = find_nonnullable_rels_walker((Node *) expr->arg, top_level);
1627 : }
1628 52776 : else if (IsA(node, NullTest))
1629 : {
1630 : /* IS NOT NULL can be considered strict, but only at top level */
1631 4284 : NullTest *expr = (NullTest *) node;
1632 :
1633 4284 : if (top_level && expr->nulltesttype == IS_NOT_NULL && !expr->argisrow)
1634 2822 : result = find_nonnullable_rels_walker((Node *) expr->arg, false);
1635 : }
1636 48492 : else if (IsA(node, BooleanTest))
1637 : {
1638 : /* Boolean tests that reject NULL are strict at top level */
1639 109 : BooleanTest *expr = (BooleanTest *) node;
1640 :
1641 109 : if (top_level &&
1642 109 : (expr->booltesttype == IS_TRUE ||
1643 109 : expr->booltesttype == IS_FALSE ||
1644 5 : expr->booltesttype == IS_NOT_UNKNOWN))
1645 104 : result = find_nonnullable_rels_walker((Node *) expr->arg, false);
1646 : }
1647 48383 : else if (IsA(node, SubPlan))
1648 : {
1649 108 : SubPlan *splan = (SubPlan *) node;
1650 :
1651 : /*
1652 : * For some types of SubPlan, we can infer strictness from Vars in the
1653 : * testexpr (the LHS of the original SubLink).
1654 : *
1655 : * For ANY_SUBLINK, if the subquery produces zero rows, the result is
1656 : * always FALSE. If the subquery produces more than one row, the
1657 : * per-row results of the testexpr are combined using OR semantics.
1658 : * Hence ANY_SUBLINK can be strict only at top level, but there it's
1659 : * as strict as the testexpr is.
1660 : *
1661 : * For ROWCOMPARE_SUBLINK, if the subquery produces zero rows, the
1662 : * result is always NULL. Otherwise, the result is as strict as the
1663 : * testexpr is. So we can check regardless of top_level.
1664 : *
1665 : * We can't prove anything for other sublink types (in particular,
1666 : * note that ALL_SUBLINK will return TRUE if the subquery is empty).
1667 : */
1668 108 : if ((top_level && splan->subLinkType == ANY_SUBLINK) ||
1669 73 : splan->subLinkType == ROWCOMPARE_SUBLINK)
1670 35 : result = find_nonnullable_rels_walker(splan->testexpr, top_level);
1671 : }
1672 48275 : else if (IsA(node, PlaceHolderVar))
1673 : {
1674 440 : PlaceHolderVar *phv = (PlaceHolderVar *) node;
1675 :
1676 : /*
1677 : * If the contained expression forces any rels non-nullable, so does
1678 : * the PHV.
1679 : */
1680 440 : result = find_nonnullable_rels_walker((Node *) phv->phexpr, top_level);
1681 :
1682 : /*
1683 : * If the PHV's syntactic scope is exactly one rel, it will be forced
1684 : * to be evaluated at that rel, and so it will behave like a Var of
1685 : * that rel: if the rel's entire output goes to null, so will the PHV.
1686 : * (If the syntactic scope is a join, we know that the PHV will go to
1687 : * null if the whole join does; but that is AND semantics while we
1688 : * need OR semantics for find_nonnullable_rels' result, so we can't do
1689 : * anything with the knowledge.)
1690 : */
1691 880 : if (phv->phlevelsup == 0 &&
1692 440 : bms_membership(phv->phrels) == BMS_SINGLETON)
1693 280 : result = bms_add_members(result, phv->phrels);
1694 : }
1695 540131 : return result;
1696 : }
1697 :
1698 : /*
1699 : * find_nonnullable_vars
1700 : * Determine which Vars are forced nonnullable by given clause.
1701 : *
1702 : * Returns the set of all level-zero Vars that are referenced in the clause in
1703 : * such a way that the clause cannot possibly return TRUE if any of these Vars
1704 : * is NULL. (It is OK to err on the side of conservatism; hence the analysis
1705 : * here is simplistic.)
1706 : *
1707 : * The semantics here are subtly different from contain_nonstrict_functions:
1708 : * that function is concerned with NULL results from arbitrary expressions,
1709 : * but here we assume that the input is a Boolean expression, and wish to
1710 : * see if NULL inputs will provably cause a FALSE-or-NULL result. We expect
1711 : * the expression to have been AND/OR flattened and converted to implicit-AND
1712 : * format (but the results are still good if it wasn't AND/OR flattened).
1713 : *
1714 : * Attnos of the identified Vars are returned in a multibitmapset (a List of
1715 : * Bitmapsets). List indexes correspond to relids (varnos), while the per-rel
1716 : * Bitmapsets hold varattnos offset by FirstLowInvalidHeapAttributeNumber.
1717 : *
1718 : * top_level is true while scanning top-level AND/OR structure; here, showing
1719 : * the result is either FALSE or NULL is good enough. top_level is false when
1720 : * we have descended below a NOT or a strict function: now we must be able to
1721 : * prove that the subexpression goes to NULL.
1722 : *
1723 : * We don't use expression_tree_walker here because we don't want to descend
1724 : * through very many kinds of nodes; only the ones we can be sure are strict.
1725 : */
1726 : List *
1727 1175 : find_nonnullable_vars(Node *clause)
1728 : {
1729 1175 : return find_nonnullable_vars_walker(clause, true);
1730 : }
1731 :
1732 : static List *
1733 7748 : find_nonnullable_vars_walker(Node *node, bool top_level)
1734 : {
1735 7748 : List *result = NIL;
1736 : ListCell *l;
1737 :
1738 7748 : if (node == NULL)
1739 35 : return NIL;
1740 7713 : if (IsA(node, Var))
1741 : {
1742 3048 : Var *var = (Var *) node;
1743 :
1744 3048 : if (var->varlevelsup == 0)
1745 3048 : result = mbms_add_member(result,
1746 : var->varno,
1747 3048 : var->varattno - FirstLowInvalidHeapAttributeNumber);
1748 : }
1749 4665 : else if (IsA(node, List))
1750 : {
1751 : /*
1752 : * At top level, we are examining an implicit-AND list: if any of the
1753 : * arms produces FALSE-or-NULL then the result is FALSE-or-NULL. If
1754 : * not at top level, we are examining the arguments of a strict
1755 : * function: if any of them produce NULL then the result of the
1756 : * function must be NULL. So in both cases, the set of nonnullable
1757 : * vars is the union of those found in the arms, and we pass down the
1758 : * top_level flag unmodified.
1759 : */
1760 7460 : foreach(l, (List *) node)
1761 : {
1762 4727 : result = mbms_add_members(result,
1763 4727 : find_nonnullable_vars_walker(lfirst(l),
1764 : top_level));
1765 : }
1766 : }
1767 1932 : else if (IsA(node, FuncExpr))
1768 : {
1769 10 : FuncExpr *expr = (FuncExpr *) node;
1770 :
1771 10 : if (func_strict(expr->funcid))
1772 10 : result = find_nonnullable_vars_walker((Node *) expr->args, false);
1773 : }
1774 1922 : else if (IsA(node, OpExpr))
1775 : {
1776 1563 : OpExpr *expr = (OpExpr *) node;
1777 :
1778 1563 : set_opfuncid(expr);
1779 1563 : if (func_strict(expr->opfuncid))
1780 1563 : result = find_nonnullable_vars_walker((Node *) expr->args, false);
1781 : }
1782 359 : else if (IsA(node, ScalarArrayOpExpr))
1783 : {
1784 0 : ScalarArrayOpExpr *expr = (ScalarArrayOpExpr *) node;
1785 :
1786 0 : if (is_strict_saop(expr, true))
1787 0 : result = find_nonnullable_vars_walker((Node *) expr->args, false);
1788 : }
1789 359 : else if (IsA(node, BoolExpr))
1790 : {
1791 98 : BoolExpr *expr = (BoolExpr *) node;
1792 :
1793 98 : switch (expr->boolop)
1794 : {
1795 0 : case AND_EXPR:
1796 :
1797 : /*
1798 : * At top level we can just recurse (to the List case), since
1799 : * the result should be the union of what we can prove in each
1800 : * arm.
1801 : */
1802 0 : if (top_level)
1803 : {
1804 0 : result = find_nonnullable_vars_walker((Node *) expr->args,
1805 : top_level);
1806 0 : break;
1807 : }
1808 :
1809 : /*
1810 : * Below top level, even if one arm produces NULL, the result
1811 : * could be FALSE (hence not NULL). However, if *all* the
1812 : * arms produce NULL then the result is NULL, so we can take
1813 : * the intersection of the sets of nonnullable vars, just as
1814 : * for OR. Fall through to share code.
1815 : */
1816 : pg_fallthrough;
1817 : case OR_EXPR:
1818 :
1819 : /*
1820 : * OR is strict if all of its arms are, so we can take the
1821 : * intersection of the sets of nonnullable vars for each arm.
1822 : * This works for both values of top_level.
1823 : */
1824 176 : foreach(l, expr->args)
1825 : {
1826 : List *subresult;
1827 :
1828 176 : subresult = find_nonnullable_vars_walker(lfirst(l),
1829 : top_level);
1830 176 : if (result == NIL) /* first subresult? */
1831 78 : result = subresult;
1832 : else
1833 98 : result = mbms_int_members(result, subresult);
1834 :
1835 : /*
1836 : * If the intersection is empty, we can stop looking. This
1837 : * also justifies the test for first-subresult above.
1838 : */
1839 176 : if (result == NIL)
1840 78 : break;
1841 : }
1842 78 : break;
1843 20 : case NOT_EXPR:
1844 : /* NOT will return null if its arg is null */
1845 20 : result = find_nonnullable_vars_walker((Node *) expr->args,
1846 : false);
1847 20 : break;
1848 0 : default:
1849 0 : elog(ERROR, "unrecognized boolop: %d", (int) expr->boolop);
1850 : break;
1851 : }
1852 : }
1853 261 : else if (IsA(node, RelabelType))
1854 : {
1855 46 : RelabelType *expr = (RelabelType *) node;
1856 :
1857 46 : result = find_nonnullable_vars_walker((Node *) expr->arg, top_level);
1858 : }
1859 215 : else if (IsA(node, CoerceViaIO))
1860 : {
1861 : /* not clear this is useful, but it can't hurt */
1862 16 : CoerceViaIO *expr = (CoerceViaIO *) node;
1863 :
1864 16 : result = find_nonnullable_vars_walker((Node *) expr->arg, false);
1865 : }
1866 199 : else if (IsA(node, ArrayCoerceExpr))
1867 : {
1868 : /* ArrayCoerceExpr is strict at the array level; ignore elemexpr */
1869 0 : ArrayCoerceExpr *expr = (ArrayCoerceExpr *) node;
1870 :
1871 0 : result = find_nonnullable_vars_walker((Node *) expr->arg, top_level);
1872 : }
1873 199 : else if (IsA(node, ConvertRowtypeExpr))
1874 : {
1875 : /* not clear this is useful, but it can't hurt */
1876 0 : ConvertRowtypeExpr *expr = (ConvertRowtypeExpr *) node;
1877 :
1878 0 : result = find_nonnullable_vars_walker((Node *) expr->arg, top_level);
1879 : }
1880 199 : else if (IsA(node, CollateExpr))
1881 : {
1882 0 : CollateExpr *expr = (CollateExpr *) node;
1883 :
1884 0 : result = find_nonnullable_vars_walker((Node *) expr->arg, top_level);
1885 : }
1886 199 : else if (IsA(node, NullTest))
1887 : {
1888 : /* IS NOT NULL can be considered strict, but only at top level */
1889 93 : NullTest *expr = (NullTest *) node;
1890 :
1891 93 : if (top_level && expr->nulltesttype == IS_NOT_NULL && !expr->argisrow)
1892 15 : result = find_nonnullable_vars_walker((Node *) expr->arg, false);
1893 : }
1894 106 : else if (IsA(node, BooleanTest))
1895 : {
1896 : /* Boolean tests that reject NULL are strict at top level */
1897 0 : BooleanTest *expr = (BooleanTest *) node;
1898 :
1899 0 : if (top_level &&
1900 0 : (expr->booltesttype == IS_TRUE ||
1901 0 : expr->booltesttype == IS_FALSE ||
1902 0 : expr->booltesttype == IS_NOT_UNKNOWN))
1903 0 : result = find_nonnullable_vars_walker((Node *) expr->arg, false);
1904 : }
1905 106 : else if (IsA(node, SubPlan))
1906 : {
1907 0 : SubPlan *splan = (SubPlan *) node;
1908 :
1909 : /* See analysis in find_nonnullable_rels_walker */
1910 0 : if ((top_level && splan->subLinkType == ANY_SUBLINK) ||
1911 0 : splan->subLinkType == ROWCOMPARE_SUBLINK)
1912 0 : result = find_nonnullable_vars_walker(splan->testexpr, top_level);
1913 : }
1914 106 : else if (IsA(node, PlaceHolderVar))
1915 : {
1916 0 : PlaceHolderVar *phv = (PlaceHolderVar *) node;
1917 :
1918 0 : result = find_nonnullable_vars_walker((Node *) phv->phexpr, top_level);
1919 : }
1920 7713 : return result;
1921 : }
1922 :
1923 : /*
1924 : * find_forced_null_vars
1925 : * Determine which Vars must be NULL for the given clause to return TRUE.
1926 : *
1927 : * This is the complement of find_nonnullable_vars: find the level-zero Vars
1928 : * that must be NULL for the clause to return TRUE. (It is OK to err on the
1929 : * side of conservatism; hence the analysis here is simplistic. In fact,
1930 : * we only detect simple "var IS NULL" tests at the top level.)
1931 : *
1932 : * As with find_nonnullable_vars, we return the varattnos of the identified
1933 : * Vars in a multibitmapset.
1934 : */
1935 : List *
1936 94211 : find_forced_null_vars(Node *node)
1937 : {
1938 94211 : List *result = NIL;
1939 : Var *var;
1940 : ListCell *l;
1941 :
1942 94211 : if (node == NULL)
1943 4452 : return NIL;
1944 : /* Check single-clause cases using subroutine */
1945 89759 : var = find_forced_null_var(node);
1946 89759 : if (var)
1947 : {
1948 1161 : result = mbms_add_member(result,
1949 : var->varno,
1950 1161 : var->varattno - FirstLowInvalidHeapAttributeNumber);
1951 : }
1952 : /* Otherwise, handle AND-conditions */
1953 88598 : else if (IsA(node, List))
1954 : {
1955 : /*
1956 : * At top level, we are examining an implicit-AND list: if any of the
1957 : * arms produces FALSE-or-NULL then the result is FALSE-or-NULL.
1958 : */
1959 89759 : foreach(l, (List *) node)
1960 : {
1961 54878 : result = mbms_add_members(result,
1962 54878 : find_forced_null_vars((Node *) lfirst(l)));
1963 : }
1964 : }
1965 53717 : else if (IsA(node, BoolExpr))
1966 : {
1967 4421 : BoolExpr *expr = (BoolExpr *) node;
1968 :
1969 : /*
1970 : * We don't bother considering the OR case, because it's fairly
1971 : * unlikely anyone would write "v1 IS NULL OR v1 IS NULL". Likewise,
1972 : * the NOT case isn't worth expending code on.
1973 : */
1974 4421 : if (expr->boolop == AND_EXPR)
1975 : {
1976 : /* At top level we can just recurse (to the List case) */
1977 0 : result = find_forced_null_vars((Node *) expr->args);
1978 : }
1979 : }
1980 89759 : return result;
1981 : }
1982 :
1983 : /*
1984 : * find_forced_null_var
1985 : * Return the Var forced null by the given clause, or NULL if it's
1986 : * not an IS NULL-type clause. For success, the clause must enforce
1987 : * *only* nullness of the particular Var, not any other conditions.
1988 : *
1989 : * This is just the single-clause case of find_forced_null_vars(), without
1990 : * any allowance for AND conditions. It's used by initsplan.c on individual
1991 : * qual clauses. The reason for not just applying find_forced_null_vars()
1992 : * is that if an AND of an IS NULL clause with something else were to somehow
1993 : * survive AND/OR flattening, initsplan.c might get fooled into discarding
1994 : * the whole clause when only the IS NULL part of it had been proved redundant.
1995 : */
1996 : Var *
1997 474725 : find_forced_null_var(Node *node)
1998 : {
1999 474725 : if (node == NULL)
2000 0 : return NULL;
2001 474725 : if (IsA(node, NullTest))
2002 : {
2003 : /* check for var IS NULL */
2004 9575 : NullTest *expr = (NullTest *) node;
2005 :
2006 9575 : if (expr->nulltesttype == IS_NULL && !expr->argisrow)
2007 : {
2008 3521 : Var *var = (Var *) expr->arg;
2009 :
2010 3521 : if (var && IsA(var, Var) &&
2011 3413 : var->varlevelsup == 0)
2012 3413 : return var;
2013 : }
2014 : }
2015 465150 : else if (IsA(node, BooleanTest))
2016 : {
2017 : /* var IS UNKNOWN is equivalent to var IS NULL */
2018 570 : BooleanTest *expr = (BooleanTest *) node;
2019 :
2020 570 : if (expr->booltesttype == IS_UNKNOWN)
2021 : {
2022 45 : Var *var = (Var *) expr->arg;
2023 :
2024 45 : if (var && IsA(var, Var) &&
2025 45 : var->varlevelsup == 0)
2026 45 : return var;
2027 : }
2028 : }
2029 471267 : return NULL;
2030 : }
2031 :
2032 : /*
2033 : * query_outputs_are_not_nullable
2034 : * Returns TRUE if the output values of the Query are certainly not NULL.
2035 : * All output columns must return non-NULL to answer TRUE.
2036 : *
2037 : * The reason this takes a Query, and not just an individual tlist expression,
2038 : * is so that we can make use of the query's WHERE/ON clauses to prove it does
2039 : * not return nulls.
2040 : *
2041 : * In current usage, the passed sub-Query hasn't yet been through any planner
2042 : * processing. This means that applying find_nonnullable_vars() to its WHERE
2043 : * clauses isn't really ideal: for lack of const-simplification, we might be
2044 : * unable to prove not-nullness in some cases where we could have proved it
2045 : * afterwards. However, we should not get any false positive results.
2046 : *
2047 : * Like the other forms of nullability analysis above, we can err on the
2048 : * side of conservatism: if we're not sure, it's okay to return FALSE.
2049 : */
2050 : bool
2051 120 : query_outputs_are_not_nullable(Query *query)
2052 : {
2053 : PlannerInfo subroot;
2054 120 : List *safe_quals = NIL;
2055 120 : List *nonnullable_vars = NIL;
2056 120 : bool computed_nonnullable_vars = false;
2057 :
2058 : /*
2059 : * If the query contains set operations, punt. The set ops themselves
2060 : * couldn't introduce nulls that weren't in their inputs, but the tlist
2061 : * present in the top-level query is just dummy and won't give us useful
2062 : * info. We could get an answer by recursing to examine each leaf query,
2063 : * but for the moment it doesn't seem worth the extra complication.
2064 : */
2065 120 : if (query->setOperations)
2066 0 : return false;
2067 :
2068 : /*
2069 : * If the query contains grouping sets, punt. Grouping sets can introduce
2070 : * NULL values, and we currently lack the PlannerInfo needed to flatten
2071 : * grouping Vars in the query's outputs.
2072 : */
2073 120 : if (query->groupingSets)
2074 5 : return false;
2075 :
2076 : /*
2077 : * We need a PlannerInfo to pass to expr_is_nonnullable. Fortunately, we
2078 : * can cons up an entirely dummy one, because only the "parse" link in the
2079 : * struct is used by expr_is_nonnullable.
2080 : */
2081 10810 : MemSet(&subroot, 0, sizeof(subroot));
2082 115 : subroot.parse = query;
2083 :
2084 : /*
2085 : * Examine each targetlist entry to prove that it can't produce NULL.
2086 : */
2087 300 : foreach_node(TargetEntry, tle, query->targetList)
2088 : {
2089 130 : Expr *expr = tle->expr;
2090 :
2091 : /* Resjunk columns can be ignored: they don't produce output values */
2092 130 : if (tle->resjunk)
2093 0 : continue;
2094 :
2095 : /*
2096 : * Look through binary relabelings, since we know those don't
2097 : * introduce nulls.
2098 : */
2099 130 : while (expr && IsA(expr, RelabelType))
2100 0 : expr = ((RelabelType *) expr)->arg;
2101 :
2102 130 : if (expr == NULL) /* paranoia */
2103 30 : return false;
2104 :
2105 : /*
2106 : * Since the subquery hasn't yet been through expression
2107 : * preprocessing, we must explicitly flatten grouping Vars and join
2108 : * alias Vars in the given expression. Note that flatten_group_exprs
2109 : * must be applied before flatten_join_alias_vars, as grouping Vars
2110 : * can wrap join alias Vars.
2111 : *
2112 : * We must also apply flatten_join_alias_vars to the quals extracted
2113 : * by find_subquery_safe_quals. We do not need to apply
2114 : * flatten_group_exprs to these quals, though, because grouping Vars
2115 : * cannot appear in jointree quals.
2116 : */
2117 :
2118 : /*
2119 : * We have verified that the query does not contain grouping sets,
2120 : * meaning the grouping Vars will not have varnullingrels that need
2121 : * preserving, so it's safe to use NULL as the root here.
2122 : */
2123 130 : if (query->hasGroupRTE)
2124 10 : expr = (Expr *) flatten_group_exprs(NULL, query, (Node *) expr);
2125 :
2126 : /*
2127 : * We won't be dealing with arbitrary expressions, so it's safe to use
2128 : * NULL as the root, so long as adjust_standard_join_alias_expression
2129 : * can handle everything the parser would make as a join alias
2130 : * expression.
2131 : */
2132 130 : expr = (Expr *) flatten_join_alias_vars(NULL, query, (Node *) expr);
2133 :
2134 : /*
2135 : * Check to see if the expr cannot be NULL. Since we're on a raw
2136 : * parse tree, we need to look up the not-null constraints from the
2137 : * system catalogs.
2138 : */
2139 130 : if (expr_is_nonnullable(&subroot, expr, NOTNULL_SOURCE_CATALOG))
2140 80 : continue;
2141 :
2142 50 : if (IsA(expr, Var))
2143 : {
2144 50 : Var *var = (Var *) expr;
2145 :
2146 : /*
2147 : * For a plain Var, even if that didn't work, we can conclude that
2148 : * the Var is not nullable if find_nonnullable_vars can find a
2149 : * "var IS NOT NULL" or similarly strict condition among the quals
2150 : * on non-outerjoined-rels. Compute the list of Vars having such
2151 : * quals if we didn't already.
2152 : */
2153 50 : if (!computed_nonnullable_vars)
2154 : {
2155 50 : find_subquery_safe_quals((Node *) query->jointree, &safe_quals);
2156 50 : safe_quals = (List *)
2157 50 : flatten_join_alias_vars(NULL, query, (Node *) safe_quals);
2158 50 : nonnullable_vars = find_nonnullable_vars((Node *) safe_quals);
2159 50 : computed_nonnullable_vars = true;
2160 : }
2161 :
2162 50 : if (!mbms_is_member(var->varno,
2163 50 : var->varattno - FirstLowInvalidHeapAttributeNumber,
2164 : nonnullable_vars))
2165 30 : return false; /* we failed to prove the Var non-null */
2166 : }
2167 : else
2168 : {
2169 : /* Punt otherwise */
2170 0 : return false;
2171 : }
2172 : }
2173 :
2174 85 : return true;
2175 : }
2176 :
2177 : /*
2178 : * find_subquery_safe_quals
2179 : * Traverse jointree to locate quals on non-outerjoined-rels.
2180 : *
2181 : * We locate all WHERE and JOIN/ON quals that constrain the rels that are not
2182 : * below the nullable side of any outer join, and add them to the *safe_quals
2183 : * list (forming a list with implicit-AND semantics). These quals can be used
2184 : * to prove non-nullability of the subquery's outputs.
2185 : *
2186 : * Top-level caller must initialize *safe_quals to NIL.
2187 : */
2188 : static void
2189 135 : find_subquery_safe_quals(Node *jtnode, List **safe_quals)
2190 : {
2191 135 : if (jtnode == NULL)
2192 0 : return;
2193 135 : if (IsA(jtnode, RangeTblRef))
2194 : {
2195 : /* Leaf node: nothing to do */
2196 60 : return;
2197 : }
2198 75 : else if (IsA(jtnode, FromExpr))
2199 : {
2200 50 : FromExpr *f = (FromExpr *) jtnode;
2201 :
2202 : /* All elements of the FROM list are allowable */
2203 155 : foreach_ptr(Node, child_node, f->fromlist)
2204 55 : find_subquery_safe_quals(child_node, safe_quals);
2205 : /* ... and its WHERE quals are too */
2206 50 : if (f->quals)
2207 15 : *safe_quals = lappend(*safe_quals, f->quals);
2208 : }
2209 25 : else if (IsA(jtnode, JoinExpr))
2210 : {
2211 25 : JoinExpr *j = (JoinExpr *) jtnode;
2212 :
2213 25 : switch (j->jointype)
2214 : {
2215 5 : case JOIN_INNER:
2216 : /* visit both children */
2217 5 : find_subquery_safe_quals(j->larg, safe_quals);
2218 5 : find_subquery_safe_quals(j->rarg, safe_quals);
2219 : /* and grab the ON quals too */
2220 5 : if (j->quals)
2221 5 : *safe_quals = lappend(*safe_quals, j->quals);
2222 5 : break;
2223 :
2224 20 : case JOIN_LEFT:
2225 : case JOIN_SEMI:
2226 : case JOIN_ANTI:
2227 :
2228 : /*
2229 : * Only the left input is possibly non-nullable; furthermore,
2230 : * the quals of this join don't constrain the left input.
2231 : * Note: we probably can't see SEMI or ANTI joins at this
2232 : * point, but if we do, we can treat them like LEFT joins.
2233 : */
2234 20 : find_subquery_safe_quals(j->larg, safe_quals);
2235 20 : break;
2236 :
2237 0 : case JOIN_RIGHT:
2238 : /* Reverse of the above case */
2239 0 : find_subquery_safe_quals(j->rarg, safe_quals);
2240 0 : break;
2241 :
2242 0 : case JOIN_FULL:
2243 : /* Neither side is non-nullable, so stop descending */
2244 0 : break;
2245 :
2246 0 : default:
2247 0 : elog(ERROR, "unrecognized join type: %d",
2248 : (int) j->jointype);
2249 : break;
2250 : }
2251 : }
2252 : else
2253 0 : elog(ERROR, "unrecognized node type: %d",
2254 : (int) nodeTag(jtnode));
2255 : }
2256 :
2257 : /*
2258 : * Can we treat a ScalarArrayOpExpr as strict?
2259 : *
2260 : * If "falseOK" is true, then a "false" result can be considered strict,
2261 : * else we need to guarantee an actual NULL result for NULL input.
2262 : *
2263 : * "foo op ALL array" is strict if the op is strict *and* we can prove
2264 : * that the array input isn't an empty array. We can check that
2265 : * for the cases of an array constant and an ARRAY[] construct.
2266 : *
2267 : * "foo op ANY array" is strict in the falseOK sense if the op is strict.
2268 : * If not falseOK, the test is the same as for "foo op ALL array".
2269 : */
2270 : static bool
2271 6378 : is_strict_saop(ScalarArrayOpExpr *expr, bool falseOK)
2272 : {
2273 : Node *rightop;
2274 :
2275 : /* The contained operator must be strict. */
2276 6378 : set_sa_opfuncid(expr);
2277 6378 : if (!func_strict(expr->opfuncid))
2278 0 : return false;
2279 : /* If ANY and falseOK, that's all we need to check. */
2280 6378 : if (expr->useOr && falseOK)
2281 6272 : return true;
2282 : /* Else, we have to see if the array is provably non-empty. */
2283 : Assert(list_length(expr->args) == 2);
2284 106 : rightop = (Node *) lsecond(expr->args);
2285 106 : if (rightop && IsA(rightop, Const))
2286 0 : {
2287 106 : Datum arraydatum = ((Const *) rightop)->constvalue;
2288 106 : bool arrayisnull = ((Const *) rightop)->constisnull;
2289 : ArrayType *arrayval;
2290 : int nitems;
2291 :
2292 106 : if (arrayisnull)
2293 0 : return false;
2294 106 : arrayval = DatumGetArrayTypeP(arraydatum);
2295 106 : nitems = ArrayGetNItems(ARR_NDIM(arrayval), ARR_DIMS(arrayval));
2296 106 : if (nitems > 0)
2297 106 : return true;
2298 : }
2299 0 : else if (rightop && IsA(rightop, ArrayExpr))
2300 : {
2301 0 : ArrayExpr *arrayexpr = (ArrayExpr *) rightop;
2302 :
2303 0 : if (arrayexpr->elements != NIL && !arrayexpr->multidims)
2304 0 : return true;
2305 : }
2306 0 : return false;
2307 : }
2308 :
2309 :
2310 : /*****************************************************************************
2311 : * Check for "pseudo-constant" clauses
2312 : *****************************************************************************/
2313 :
2314 : /*
2315 : * is_pseudo_constant_clause
2316 : * Detect whether an expression is "pseudo constant", ie, it contains no
2317 : * variables of the current query level and no uses of volatile functions.
2318 : * Such an expr is not necessarily a true constant: it can still contain
2319 : * Params and outer-level Vars, not to mention functions whose results
2320 : * may vary from one statement to the next. However, the expr's value
2321 : * will be constant over any one scan of the current query, so it can be
2322 : * used as, eg, an indexscan key. (Actually, the condition for indexscan
2323 : * keys is weaker than this; see is_pseudo_constant_for_index().)
2324 : *
2325 : * CAUTION: this function omits to test for one very important class of
2326 : * not-constant expressions, namely aggregates (Aggrefs). In current usage
2327 : * this is only applied to WHERE clauses and so a check for Aggrefs would be
2328 : * a waste of cycles; but be sure to also check contain_agg_clause() if you
2329 : * want to know about pseudo-constness in other contexts. The same goes
2330 : * for window functions (WindowFuncs).
2331 : */
2332 : bool
2333 4772 : is_pseudo_constant_clause(Node *clause)
2334 : {
2335 : /*
2336 : * We could implement this check in one recursive scan. But since the
2337 : * check for volatile functions is both moderately expensive and unlikely
2338 : * to fail, it seems better to look for Vars first and only check for
2339 : * volatile functions if we find no Vars.
2340 : */
2341 4772 : if (!contain_var_clause(clause) &&
2342 4772 : !contain_volatile_functions(clause))
2343 4772 : return true;
2344 0 : return false;
2345 : }
2346 :
2347 : /*
2348 : * is_pseudo_constant_clause_relids
2349 : * Same as above, except caller already has available the var membership
2350 : * of the expression; this lets us avoid the contain_var_clause() scan.
2351 : */
2352 : bool
2353 353821 : is_pseudo_constant_clause_relids(Node *clause, Relids relids)
2354 : {
2355 353821 : if (bms_is_empty(relids) &&
2356 347360 : !contain_volatile_functions(clause))
2357 347360 : return true;
2358 6461 : return false;
2359 : }
2360 :
2361 :
2362 : /*****************************************************************************
2363 : * *
2364 : * General clause-manipulating routines *
2365 : * *
2366 : *****************************************************************************/
2367 :
2368 : /*
2369 : * NumRelids
2370 : * (formerly clause_relids)
2371 : *
2372 : * Returns the number of different base relations referenced in 'clause'.
2373 : */
2374 : int
2375 1407 : NumRelids(PlannerInfo *root, Node *clause)
2376 : {
2377 : int result;
2378 1407 : Relids varnos = pull_varnos(root, clause);
2379 :
2380 1407 : varnos = bms_del_members(varnos, root->outer_join_rels);
2381 1407 : result = bms_num_members(varnos);
2382 1407 : bms_free(varnos);
2383 1407 : return result;
2384 : }
2385 :
2386 : /*
2387 : * CommuteOpExpr: commute a binary operator clause
2388 : *
2389 : * XXX the clause is destructively modified!
2390 : */
2391 : void
2392 18838 : CommuteOpExpr(OpExpr *clause)
2393 : {
2394 : Oid opoid;
2395 : Node *temp;
2396 :
2397 : /* Sanity checks: caller is at fault if these fail */
2398 37676 : if (!is_opclause(clause) ||
2399 18838 : list_length(clause->args) != 2)
2400 0 : elog(ERROR, "cannot commute non-binary-operator clause");
2401 :
2402 18838 : opoid = get_commutator(clause->opno);
2403 :
2404 18838 : if (!OidIsValid(opoid))
2405 0 : elog(ERROR, "could not find commutator for operator %u",
2406 : clause->opno);
2407 :
2408 : /*
2409 : * modify the clause in-place!
2410 : */
2411 18838 : clause->opno = opoid;
2412 18838 : clause->opfuncid = InvalidOid;
2413 : /* opresulttype, opretset, opcollid, inputcollid need not change */
2414 :
2415 18838 : temp = linitial(clause->args);
2416 18838 : linitial(clause->args) = lsecond(clause->args);
2417 18838 : lsecond(clause->args) = temp;
2418 18838 : }
2419 :
2420 : /*
2421 : * Helper for eval_const_expressions: check that datatype of an attribute
2422 : * is still what it was when the expression was parsed. This is needed to
2423 : * guard against improper simplification after ALTER COLUMN TYPE. (XXX we
2424 : * may well need to make similar checks elsewhere?)
2425 : *
2426 : * rowtypeid may come from a whole-row Var, and therefore it can be a domain
2427 : * over composite, but for this purpose we only care about checking the type
2428 : * of a contained field.
2429 : */
2430 : static bool
2431 594 : rowtype_field_matches(Oid rowtypeid, int fieldnum,
2432 : Oid expectedtype, int32 expectedtypmod,
2433 : Oid expectedcollation)
2434 : {
2435 : TupleDesc tupdesc;
2436 : Form_pg_attribute attr;
2437 :
2438 : /* No issue for RECORD, since there is no way to ALTER such a type */
2439 594 : if (rowtypeid == RECORDOID)
2440 42 : return true;
2441 552 : tupdesc = lookup_rowtype_tupdesc_domain(rowtypeid, -1, false);
2442 552 : if (fieldnum <= 0 || fieldnum > tupdesc->natts)
2443 : {
2444 0 : ReleaseTupleDesc(tupdesc);
2445 0 : return false;
2446 : }
2447 552 : attr = TupleDescAttr(tupdesc, fieldnum - 1);
2448 552 : if (attr->attisdropped ||
2449 552 : attr->atttypid != expectedtype ||
2450 552 : attr->atttypmod != expectedtypmod ||
2451 552 : attr->attcollation != expectedcollation)
2452 : {
2453 0 : ReleaseTupleDesc(tupdesc);
2454 0 : return false;
2455 : }
2456 552 : ReleaseTupleDesc(tupdesc);
2457 552 : return true;
2458 : }
2459 :
2460 :
2461 : /*--------------------
2462 : * eval_const_expressions
2463 : *
2464 : * Reduce any recognizably constant subexpressions of the given
2465 : * expression tree, for example "2 + 2" => "4". More interestingly,
2466 : * we can reduce certain boolean expressions even when they contain
2467 : * non-constant subexpressions: "x OR true" => "true" no matter what
2468 : * the subexpression x is. (XXX We assume that no such subexpression
2469 : * will have important side-effects, which is not necessarily a good
2470 : * assumption in the presence of user-defined functions; do we need a
2471 : * pg_proc flag that prevents discarding the execution of a function?)
2472 : *
2473 : * We do understand that certain functions may deliver non-constant
2474 : * results even with constant inputs, "nextval()" being the classic
2475 : * example. Functions that are not marked "immutable" in pg_proc
2476 : * will not be pre-evaluated here, although we will reduce their
2477 : * arguments as far as possible.
2478 : *
2479 : * Whenever a function is eliminated from the expression by means of
2480 : * constant-expression evaluation or inlining, we add the function to
2481 : * root->glob->invalItems. This ensures the plan is known to depend on
2482 : * such functions, even though they aren't referenced anymore.
2483 : *
2484 : * We assume that the tree has already been type-checked and contains
2485 : * only operators and functions that are reasonable to try to execute.
2486 : *
2487 : * NOTE: "root" can be passed as NULL if the caller never wants to do any
2488 : * Param substitutions nor receive info about inlined functions nor reduce
2489 : * NullTest for Vars to constant true or constant false.
2490 : *
2491 : * NOTE: the planner assumes that this will always flatten nested AND and
2492 : * OR clauses into N-argument form. See comments in prepqual.c.
2493 : *
2494 : * NOTE: another critical effect is that any function calls that require
2495 : * default arguments will be expanded, and named-argument calls will be
2496 : * converted to positional notation. The executor won't handle either.
2497 : *--------------------
2498 : */
2499 : Node *
2500 901444 : eval_const_expressions(PlannerInfo *root, Node *node)
2501 : {
2502 : eval_const_expressions_context context;
2503 :
2504 901444 : if (root)
2505 757090 : context.boundParams = root->glob->boundParams; /* bound Params */
2506 : else
2507 144354 : context.boundParams = NULL;
2508 901444 : context.root = root; /* for inlined-function dependencies */
2509 901444 : context.active_fns = NIL; /* nothing being recursively simplified */
2510 901444 : context.case_val = NULL; /* no CASE being examined */
2511 901444 : context.estimate = false; /* safe transformations only */
2512 901444 : return eval_const_expressions_mutator(node, &context);
2513 : }
2514 :
2515 : #define MIN_ARRAY_SIZE_FOR_HASHED_SAOP 9
2516 : /*--------------------
2517 : * convert_saop_to_hashed_saop
2518 : *
2519 : * Recursively search 'node' for ScalarArrayOpExprs and fill in the hash
2520 : * function for any ScalarArrayOpExpr that looks like it would be useful to
2521 : * evaluate using a hash table rather than a linear search.
2522 : *
2523 : * We'll use a hash table if all of the following conditions are met:
2524 : * 1. The 2nd argument of the array contain only Consts.
2525 : * 2. useOr is true or there is a valid negator operator for the
2526 : * ScalarArrayOpExpr's opno.
2527 : * 3. There's valid hash function for both left and righthand operands and
2528 : * these hash functions are the same.
2529 : * 4. If the array contains enough elements for us to consider it to be
2530 : * worthwhile using a hash table rather than a linear search.
2531 : */
2532 : void
2533 658427 : convert_saop_to_hashed_saop(Node *node)
2534 : {
2535 658427 : (void) convert_saop_to_hashed_saop_walker(node, NULL);
2536 658427 : }
2537 :
2538 : static bool
2539 4847481 : convert_saop_to_hashed_saop_walker(Node *node, void *context)
2540 : {
2541 4847481 : if (node == NULL)
2542 112921 : return false;
2543 :
2544 4734560 : if (IsA(node, ScalarArrayOpExpr))
2545 : {
2546 25582 : ScalarArrayOpExpr *saop = (ScalarArrayOpExpr *) node;
2547 25582 : Node *leftarg = (Node *) linitial(saop->args);
2548 25582 : Node *arrayarg = (Node *) lsecond(saop->args);
2549 : Oid lefthashfunc;
2550 : Oid righthashfunc;
2551 :
2552 25582 : if (arrayarg && IsA(arrayarg, Const) &&
2553 13061 : !((Const *) arrayarg)->constisnull)
2554 : {
2555 13036 : if (saop->useOr)
2556 : {
2557 11182 : if (get_op_hash_functions_ext(saop->opno, exprType(leftarg),
2558 10905 : &lefthashfunc, &righthashfunc) &&
2559 10905 : lefthashfunc == righthashfunc)
2560 : {
2561 10868 : Datum arrdatum = ((Const *) arrayarg)->constvalue;
2562 10868 : ArrayType *arr = (ArrayType *) DatumGetPointer(arrdatum);
2563 : int nitems;
2564 :
2565 : /*
2566 : * Only fill in the hash functions if the array looks
2567 : * large enough for it to be worth hashing instead of
2568 : * doing a linear search.
2569 : */
2570 10868 : nitems = ArrayGetNItems(ARR_NDIM(arr), ARR_DIMS(arr));
2571 :
2572 10868 : if (nitems >= MIN_ARRAY_SIZE_FOR_HASHED_SAOP)
2573 : {
2574 : /* Looks good. Fill in the hash functions */
2575 161 : saop->hashfuncid = lefthashfunc;
2576 : }
2577 12581 : return false;
2578 : }
2579 : }
2580 : else /* !saop->useOr */
2581 : {
2582 1854 : Oid negator = get_negator(saop->opno);
2583 :
2584 : /*
2585 : * Check if this is a NOT IN using an operator whose negator
2586 : * is hashable. If so we can still build a hash table and
2587 : * just ensure the lookup items are not in the hash table.
2588 : */
2589 3708 : if (OidIsValid(negator) &&
2590 1854 : get_op_hash_functions_ext(negator, exprType(leftarg),
2591 1713 : &lefthashfunc, &righthashfunc) &&
2592 1713 : lefthashfunc == righthashfunc)
2593 : {
2594 1713 : Datum arrdatum = ((Const *) arrayarg)->constvalue;
2595 1713 : ArrayType *arr = (ArrayType *) DatumGetPointer(arrdatum);
2596 : int nitems;
2597 :
2598 : /*
2599 : * Only fill in the hash functions if the array looks
2600 : * large enough for it to be worth hashing instead of
2601 : * doing a linear search.
2602 : */
2603 1713 : nitems = ArrayGetNItems(ARR_NDIM(arr), ARR_DIMS(arr));
2604 :
2605 1713 : if (nitems >= MIN_ARRAY_SIZE_FOR_HASHED_SAOP)
2606 : {
2607 : /* Looks good. Fill in the hash functions */
2608 82 : saop->hashfuncid = lefthashfunc;
2609 :
2610 : /*
2611 : * Also set the negfuncid. The executor will need
2612 : * that to perform hashtable lookups.
2613 : */
2614 82 : saop->negfuncid = get_opcode(negator);
2615 : }
2616 1713 : return false;
2617 : }
2618 : }
2619 : }
2620 : }
2621 :
2622 4721979 : return expression_tree_walker(node, convert_saop_to_hashed_saop_walker, NULL);
2623 : }
2624 :
2625 :
2626 : /*--------------------
2627 : * estimate_expression_value
2628 : *
2629 : * This function attempts to estimate the value of an expression for
2630 : * planning purposes. It is in essence a more aggressive version of
2631 : * eval_const_expressions(): we will perform constant reductions that are
2632 : * not necessarily 100% safe, but are reasonable for estimation purposes.
2633 : *
2634 : * Currently the extra steps that are taken in this mode are:
2635 : * 1. Substitute values for Params, where a bound Param value has been made
2636 : * available by the caller of planner(), even if the Param isn't marked
2637 : * constant. This effectively means that we plan using the first supplied
2638 : * value of the Param.
2639 : * 2. Fold stable, as well as immutable, functions to constants.
2640 : * 3. Reduce PlaceHolderVar nodes to their contained expressions.
2641 : *--------------------
2642 : */
2643 : Node *
2644 715317 : estimate_expression_value(PlannerInfo *root, Node *node)
2645 : {
2646 : eval_const_expressions_context context;
2647 :
2648 715317 : context.boundParams = root->glob->boundParams; /* bound Params */
2649 : /* we do not need to mark the plan as depending on inlined functions */
2650 715317 : context.root = NULL;
2651 715317 : context.active_fns = NIL; /* nothing being recursively simplified */
2652 715317 : context.case_val = NULL; /* no CASE being examined */
2653 715317 : context.estimate = true; /* unsafe transformations OK */
2654 715317 : return eval_const_expressions_mutator(node, &context);
2655 : }
2656 :
2657 : /*
2658 : * The generic case in eval_const_expressions_mutator is to recurse using
2659 : * expression_tree_mutator, which will copy the given node unchanged but
2660 : * const-simplify its arguments (if any) as far as possible. If the node
2661 : * itself does immutable processing, and each of its arguments were reduced
2662 : * to a Const, we can then reduce it to a Const using evaluate_expr. (Some
2663 : * node types need more complicated logic; for example, a CASE expression
2664 : * might be reducible to a constant even if not all its subtrees are.)
2665 : */
2666 : #define ece_generic_processing(node) \
2667 : expression_tree_mutator((Node *) (node), eval_const_expressions_mutator, \
2668 : context)
2669 :
2670 : /*
2671 : * Check whether all arguments of the given node were reduced to Consts.
2672 : * By going directly to expression_tree_walker, contain_non_const_walker
2673 : * is not applied to the node itself, only to its children.
2674 : */
2675 : #define ece_all_arguments_const(node) \
2676 : (!expression_tree_walker((Node *) (node), contain_non_const_walker, NULL))
2677 :
2678 : /* Generic macro for applying evaluate_expr */
2679 : #define ece_evaluate_expr(node) \
2680 : ((Node *) evaluate_expr((Expr *) (node), \
2681 : exprType((Node *) (node)), \
2682 : exprTypmod((Node *) (node)), \
2683 : exprCollation((Node *) (node))))
2684 :
2685 : /*
2686 : * Recursive guts of eval_const_expressions/estimate_expression_value
2687 : */
2688 : static Node *
2689 7170124 : eval_const_expressions_mutator(Node *node,
2690 : eval_const_expressions_context *context)
2691 : {
2692 :
2693 : /* since this function recurses, it could be driven to stack overflow */
2694 7170124 : check_stack_depth();
2695 :
2696 7170124 : if (node == NULL)
2697 310211 : return NULL;
2698 6859913 : switch (nodeTag(node))
2699 : {
2700 112176 : case T_Param:
2701 : {
2702 112176 : Param *param = (Param *) node;
2703 112176 : ParamListInfo paramLI = context->boundParams;
2704 :
2705 : /* Look to see if we've been given a value for this Param */
2706 112176 : if (param->paramkind == PARAM_EXTERN &&
2707 32961 : paramLI != NULL &&
2708 32961 : param->paramid > 0 &&
2709 32961 : param->paramid <= paramLI->numParams)
2710 : {
2711 : ParamExternData *prm;
2712 : ParamExternData prmdata;
2713 :
2714 : /*
2715 : * Give hook a chance in case parameter is dynamic. Tell
2716 : * it that this fetch is speculative, so it should avoid
2717 : * erroring out if parameter is unavailable.
2718 : */
2719 32961 : if (paramLI->paramFetch != NULL)
2720 4274 : prm = paramLI->paramFetch(paramLI, param->paramid,
2721 : true, &prmdata);
2722 : else
2723 28687 : prm = ¶mLI->params[param->paramid - 1];
2724 :
2725 : /*
2726 : * We don't just check OidIsValid, but insist that the
2727 : * fetched type match the Param, just in case the hook did
2728 : * something unexpected. No need to throw an error here
2729 : * though; leave that for runtime.
2730 : */
2731 32961 : if (OidIsValid(prm->ptype) &&
2732 32961 : prm->ptype == param->paramtype)
2733 : {
2734 : /* OK to substitute parameter value? */
2735 32961 : if (context->estimate ||
2736 32961 : (prm->pflags & PARAM_FLAG_CONST))
2737 : {
2738 : /*
2739 : * Return a Const representing the param value.
2740 : * Must copy pass-by-ref datatypes, since the
2741 : * Param might be in a memory context
2742 : * shorter-lived than our output plan should be.
2743 : */
2744 : int16 typLen;
2745 : bool typByVal;
2746 : Datum pval;
2747 : Const *con;
2748 :
2749 32961 : get_typlenbyval(param->paramtype,
2750 : &typLen, &typByVal);
2751 32961 : if (prm->isnull || typByVal)
2752 20687 : pval = prm->value;
2753 : else
2754 12274 : pval = datumCopy(prm->value, typByVal, typLen);
2755 32961 : con = makeConst(param->paramtype,
2756 : param->paramtypmod,
2757 : param->paramcollid,
2758 : (int) typLen,
2759 : pval,
2760 32961 : prm->isnull,
2761 : typByVal);
2762 32961 : con->location = param->location;
2763 32961 : return (Node *) con;
2764 : }
2765 : }
2766 : }
2767 :
2768 : /*
2769 : * Not replaceable, so just copy the Param (no need to
2770 : * recurse)
2771 : */
2772 79215 : return (Node *) copyObject(param);
2773 : }
2774 3092 : case T_WindowFunc:
2775 : {
2776 3092 : WindowFunc *expr = (WindowFunc *) node;
2777 3092 : Oid funcid = expr->winfnoid;
2778 : List *args;
2779 : Expr *aggfilter;
2780 : HeapTuple func_tuple;
2781 : WindowFunc *newexpr;
2782 :
2783 : /*
2784 : * We can't really simplify a WindowFunc node, but we mustn't
2785 : * just fall through to the default processing, because we
2786 : * have to apply expand_function_arguments to its argument
2787 : * list. That takes care of inserting default arguments and
2788 : * expanding named-argument notation.
2789 : */
2790 3092 : func_tuple = SearchSysCache1(PROCOID, ObjectIdGetDatum(funcid));
2791 3092 : if (!HeapTupleIsValid(func_tuple))
2792 0 : elog(ERROR, "cache lookup failed for function %u", funcid);
2793 :
2794 3092 : args = expand_function_arguments(expr->args,
2795 : false, expr->wintype,
2796 : func_tuple);
2797 :
2798 3092 : ReleaseSysCache(func_tuple);
2799 :
2800 : /* Now, recursively simplify the args (which are a List) */
2801 : args = (List *)
2802 3092 : expression_tree_mutator((Node *) args,
2803 : eval_const_expressions_mutator,
2804 : context);
2805 : /* ... and the filter expression, which isn't */
2806 : aggfilter = (Expr *)
2807 3092 : eval_const_expressions_mutator((Node *) expr->aggfilter,
2808 : context);
2809 :
2810 : /* And build the replacement WindowFunc node */
2811 3092 : newexpr = makeNode(WindowFunc);
2812 3092 : newexpr->winfnoid = expr->winfnoid;
2813 3092 : newexpr->wintype = expr->wintype;
2814 3092 : newexpr->wincollid = expr->wincollid;
2815 3092 : newexpr->inputcollid = expr->inputcollid;
2816 3092 : newexpr->args = args;
2817 3092 : newexpr->aggfilter = aggfilter;
2818 3092 : newexpr->runCondition = expr->runCondition;
2819 3092 : newexpr->winref = expr->winref;
2820 3092 : newexpr->winstar = expr->winstar;
2821 3092 : newexpr->winagg = expr->winagg;
2822 3092 : newexpr->ignore_nulls = expr->ignore_nulls;
2823 3092 : newexpr->location = expr->location;
2824 :
2825 3092 : return (Node *) newexpr;
2826 : }
2827 382204 : case T_FuncExpr:
2828 : {
2829 382204 : FuncExpr *expr = (FuncExpr *) node;
2830 382204 : List *args = expr->args;
2831 : Expr *simple;
2832 : FuncExpr *newexpr;
2833 :
2834 : /*
2835 : * Code for op/func reduction is pretty bulky, so split it out
2836 : * as a separate function. Note: exprTypmod normally returns
2837 : * -1 for a FuncExpr, but not when the node is recognizably a
2838 : * length coercion; we want to preserve the typmod in the
2839 : * eventual Const if so.
2840 : */
2841 382204 : simple = simplify_function(expr->funcid,
2842 : expr->funcresulttype,
2843 : exprTypmod(node),
2844 : expr->funccollid,
2845 : expr->inputcollid,
2846 : &args,
2847 382204 : expr->funcvariadic,
2848 : true,
2849 : true,
2850 : context);
2851 380336 : if (simple) /* successfully simplified it */
2852 111321 : return (Node *) simple;
2853 :
2854 : /*
2855 : * The expression cannot be simplified any further, so build
2856 : * and return a replacement FuncExpr node using the
2857 : * possibly-simplified arguments. Note that we have also
2858 : * converted the argument list to positional notation.
2859 : */
2860 269015 : newexpr = makeNode(FuncExpr);
2861 269015 : newexpr->funcid = expr->funcid;
2862 269015 : newexpr->funcresulttype = expr->funcresulttype;
2863 269015 : newexpr->funcretset = expr->funcretset;
2864 269015 : newexpr->funcvariadic = expr->funcvariadic;
2865 269015 : newexpr->funcformat = expr->funcformat;
2866 269015 : newexpr->funccollid = expr->funccollid;
2867 269015 : newexpr->inputcollid = expr->inputcollid;
2868 269015 : newexpr->args = args;
2869 269015 : newexpr->location = expr->location;
2870 269015 : return (Node *) newexpr;
2871 : }
2872 38285 : case T_Aggref:
2873 38285 : node = ece_generic_processing(node);
2874 38285 : if (context->root != NULL)
2875 38275 : return simplify_aggref((Aggref *) node, context);
2876 10 : return node;
2877 558483 : case T_OpExpr:
2878 : {
2879 558483 : OpExpr *expr = (OpExpr *) node;
2880 558483 : List *args = expr->args;
2881 : Expr *simple;
2882 : OpExpr *newexpr;
2883 :
2884 : /*
2885 : * Need to get OID of underlying function. Okay to scribble
2886 : * on input to this extent.
2887 : */
2888 558483 : set_opfuncid(expr);
2889 :
2890 : /*
2891 : * Code for op/func reduction is pretty bulky, so split it out
2892 : * as a separate function.
2893 : */
2894 558483 : simple = simplify_function(expr->opfuncid,
2895 : expr->opresulttype, -1,
2896 : expr->opcollid,
2897 : expr->inputcollid,
2898 : &args,
2899 : false,
2900 : true,
2901 : true,
2902 : context);
2903 557701 : if (simple) /* successfully simplified it */
2904 20270 : return (Node *) simple;
2905 :
2906 : /*
2907 : * If the operator is boolean equality or inequality, we know
2908 : * how to simplify cases involving one constant and one
2909 : * non-constant argument.
2910 : */
2911 537431 : if (expr->opno == BooleanEqualOperator ||
2912 535775 : expr->opno == BooleanNotEqualOperator)
2913 : {
2914 1796 : simple = (Expr *) simplify_boolean_equality(expr->opno,
2915 : args);
2916 1796 : if (simple) /* successfully simplified it */
2917 1311 : return (Node *) simple;
2918 : }
2919 :
2920 : /*
2921 : * The expression cannot be simplified any further, so build
2922 : * and return a replacement OpExpr node using the
2923 : * possibly-simplified arguments.
2924 : */
2925 536120 : newexpr = makeNode(OpExpr);
2926 536120 : newexpr->opno = expr->opno;
2927 536120 : newexpr->opfuncid = expr->opfuncid;
2928 536120 : newexpr->opresulttype = expr->opresulttype;
2929 536120 : newexpr->opretset = expr->opretset;
2930 536120 : newexpr->opcollid = expr->opcollid;
2931 536120 : newexpr->inputcollid = expr->inputcollid;
2932 536120 : newexpr->args = args;
2933 536120 : newexpr->location = expr->location;
2934 536120 : return (Node *) newexpr;
2935 : }
2936 960 : case T_DistinctExpr:
2937 : {
2938 960 : DistinctExpr *expr = (DistinctExpr *) node;
2939 : List *args;
2940 : ListCell *arg;
2941 960 : bool has_null_input = false;
2942 960 : bool all_null_input = true;
2943 960 : bool has_nonconst_input = false;
2944 960 : bool has_nullable_nonconst = false;
2945 : Expr *simple;
2946 : DistinctExpr *newexpr;
2947 :
2948 : /*
2949 : * Reduce constants in the DistinctExpr's arguments. We know
2950 : * args is either NIL or a List node, so we can call
2951 : * expression_tree_mutator directly rather than recursing to
2952 : * self.
2953 : */
2954 960 : args = (List *) expression_tree_mutator((Node *) expr->args,
2955 : eval_const_expressions_mutator,
2956 : context);
2957 :
2958 : /*
2959 : * We must do our own check for NULLs because DistinctExpr has
2960 : * different results for NULL input than the underlying
2961 : * operator does. We also check if any non-constant input is
2962 : * potentially nullable.
2963 : */
2964 2880 : foreach(arg, args)
2965 : {
2966 1920 : if (IsA(lfirst(arg), Const))
2967 : {
2968 335 : has_null_input |= ((Const *) lfirst(arg))->constisnull;
2969 335 : all_null_input &= ((Const *) lfirst(arg))->constisnull;
2970 : }
2971 : else
2972 : {
2973 1585 : has_nonconst_input = true;
2974 1585 : all_null_input = false;
2975 :
2976 1585 : if (!has_nullable_nonconst &&
2977 940 : !expr_is_nonnullable(context->root,
2978 940 : (Expr *) lfirst(arg),
2979 : NOTNULL_SOURCE_HASHTABLE))
2980 855 : has_nullable_nonconst = true;
2981 : }
2982 : }
2983 :
2984 960 : if (!has_nonconst_input)
2985 : {
2986 : /*
2987 : * All inputs are constants. We can optimize this out
2988 : * completely.
2989 : */
2990 :
2991 : /* all nulls? then not distinct */
2992 45 : if (all_null_input)
2993 10 : return makeBoolConst(false, false);
2994 :
2995 : /* one null? then distinct */
2996 35 : if (has_null_input)
2997 15 : return makeBoolConst(true, false);
2998 :
2999 : /* otherwise try to evaluate the '=' operator */
3000 : /* (NOT okay to try to inline it, though!) */
3001 :
3002 : /*
3003 : * Need to get OID of underlying function. Okay to
3004 : * scribble on input to this extent.
3005 : */
3006 20 : set_opfuncid((OpExpr *) expr); /* rely on struct
3007 : * equivalence */
3008 :
3009 : /*
3010 : * Code for op/func reduction is pretty bulky, so split it
3011 : * out as a separate function.
3012 : */
3013 20 : simple = simplify_function(expr->opfuncid,
3014 : expr->opresulttype, -1,
3015 : expr->opcollid,
3016 : expr->inputcollid,
3017 : &args,
3018 : false,
3019 : false,
3020 : false,
3021 : context);
3022 20 : if (simple) /* successfully simplified it */
3023 : {
3024 : /*
3025 : * Since the underlying operator is "=", must negate
3026 : * its result
3027 : */
3028 20 : Const *csimple = castNode(Const, simple);
3029 :
3030 20 : csimple->constvalue =
3031 20 : BoolGetDatum(!DatumGetBool(csimple->constvalue));
3032 20 : return (Node *) csimple;
3033 : }
3034 : }
3035 915 : else if (!has_nullable_nonconst)
3036 : {
3037 : /*
3038 : * There are non-constant inputs, but since all of them
3039 : * are proven non-nullable, "IS DISTINCT FROM" semantics
3040 : * are much simpler.
3041 : */
3042 :
3043 : OpExpr *eqexpr;
3044 :
3045 : /*
3046 : * If one input is an explicit NULL constant, and the
3047 : * other is a non-nullable expression, the result is
3048 : * always TRUE.
3049 : */
3050 60 : if (has_null_input)
3051 20 : return makeBoolConst(true, false);
3052 :
3053 : /*
3054 : * Otherwise, both inputs are known non-nullable. In this
3055 : * case, "IS DISTINCT FROM" is equivalent to the standard
3056 : * inequality operator (usually "<>"). We convert this to
3057 : * an OpExpr, which is a more efficient representation for
3058 : * the planner. It can enable the use of partial indexes
3059 : * and constraint exclusion. Furthermore, if the clause
3060 : * is negated (ie, "IS NOT DISTINCT FROM"), the resulting
3061 : * "=" operator can allow the planner to use index scans,
3062 : * merge joins, hash joins, and EC-based qual deductions.
3063 : */
3064 40 : eqexpr = makeNode(OpExpr);
3065 40 : eqexpr->opno = expr->opno;
3066 40 : eqexpr->opfuncid = expr->opfuncid;
3067 40 : eqexpr->opresulttype = BOOLOID;
3068 40 : eqexpr->opretset = expr->opretset;
3069 40 : eqexpr->opcollid = expr->opcollid;
3070 40 : eqexpr->inputcollid = expr->inputcollid;
3071 40 : eqexpr->args = args;
3072 40 : eqexpr->location = expr->location;
3073 :
3074 40 : return eval_const_expressions_mutator(negate_clause((Node *) eqexpr),
3075 : context);
3076 : }
3077 855 : else if (has_null_input)
3078 : {
3079 : /*
3080 : * One input is a nullable non-constant expression, and
3081 : * the other is an explicit NULL constant. We can
3082 : * transform this to a NullTest with !argisrow, which is
3083 : * much more amenable to optimization.
3084 : */
3085 :
3086 40 : NullTest *nt = makeNode(NullTest);
3087 :
3088 80 : nt->arg = (Expr *) (IsA(linitial(args), Const) ?
3089 40 : lsecond(args) : linitial(args));
3090 40 : nt->nulltesttype = IS_NOT_NULL;
3091 :
3092 : /*
3093 : * argisrow = false is correct whether or not arg is
3094 : * composite
3095 : */
3096 40 : nt->argisrow = false;
3097 40 : nt->location = expr->location;
3098 :
3099 40 : return eval_const_expressions_mutator((Node *) nt, context);
3100 : }
3101 :
3102 : /*
3103 : * The expression cannot be simplified any further, so build
3104 : * and return a replacement DistinctExpr node using the
3105 : * possibly-simplified arguments.
3106 : */
3107 815 : newexpr = makeNode(DistinctExpr);
3108 815 : newexpr->opno = expr->opno;
3109 815 : newexpr->opfuncid = expr->opfuncid;
3110 815 : newexpr->opresulttype = expr->opresulttype;
3111 815 : newexpr->opretset = expr->opretset;
3112 815 : newexpr->opcollid = expr->opcollid;
3113 815 : newexpr->inputcollid = expr->inputcollid;
3114 815 : newexpr->args = args;
3115 815 : newexpr->location = expr->location;
3116 815 : return (Node *) newexpr;
3117 : }
3118 904 : case T_NullIfExpr:
3119 : {
3120 : NullIfExpr *expr;
3121 : ListCell *arg;
3122 904 : bool has_nonconst_input = false;
3123 :
3124 : /* Copy the node and const-simplify its arguments */
3125 904 : expr = (NullIfExpr *) ece_generic_processing(node);
3126 :
3127 : /* If either argument is NULL they can't be equal */
3128 2707 : foreach(arg, expr->args)
3129 : {
3130 1808 : if (!IsA(lfirst(arg), Const))
3131 878 : has_nonconst_input = true;
3132 930 : else if (((Const *) lfirst(arg))->constisnull)
3133 5 : return (Node *) linitial(expr->args);
3134 : }
3135 :
3136 : /*
3137 : * Need to get OID of underlying function before checking if
3138 : * the function is OK to evaluate.
3139 : */
3140 899 : set_opfuncid((OpExpr *) expr);
3141 :
3142 930 : if (!has_nonconst_input &&
3143 31 : ece_function_is_safe(expr->opfuncid, context))
3144 31 : return ece_evaluate_expr(expr);
3145 :
3146 868 : return (Node *) expr;
3147 : }
3148 29384 : case T_ScalarArrayOpExpr:
3149 : {
3150 : ScalarArrayOpExpr *saop;
3151 :
3152 : /* Copy the node and const-simplify its arguments */
3153 29384 : saop = (ScalarArrayOpExpr *) ece_generic_processing(node);
3154 :
3155 : /* Make sure we know underlying function */
3156 29384 : set_sa_opfuncid(saop);
3157 :
3158 : /*
3159 : * If all arguments are Consts, and it's a safe function, we
3160 : * can fold to a constant
3161 : */
3162 29653 : if (ece_all_arguments_const(saop) &&
3163 269 : ece_function_is_safe(saop->opfuncid, context))
3164 269 : return ece_evaluate_expr(saop);
3165 29115 : return (Node *) saop;
3166 : }
3167 147321 : case T_BoolExpr:
3168 : {
3169 147321 : BoolExpr *expr = (BoolExpr *) node;
3170 :
3171 147321 : switch (expr->boolop)
3172 : {
3173 15354 : case OR_EXPR:
3174 : {
3175 : List *newargs;
3176 15354 : bool haveNull = false;
3177 15354 : bool forceTrue = false;
3178 :
3179 15354 : newargs = simplify_or_arguments(expr->args,
3180 : context,
3181 : &haveNull,
3182 : &forceTrue);
3183 15354 : if (forceTrue)
3184 106 : return makeBoolConst(true, false);
3185 15248 : if (haveNull)
3186 3802 : newargs = lappend(newargs,
3187 3802 : makeBoolConst(false, true));
3188 : /* If all the inputs are FALSE, result is FALSE */
3189 15248 : if (newargs == NIL)
3190 23 : return makeBoolConst(false, false);
3191 :
3192 : /*
3193 : * If only one nonconst-or-NULL input, it's the
3194 : * result
3195 : */
3196 15225 : if (list_length(newargs) == 1)
3197 87 : return (Node *) linitial(newargs);
3198 : /* Else we still need an OR node */
3199 15138 : return (Node *) make_orclause(newargs);
3200 : }
3201 116987 : case AND_EXPR:
3202 : {
3203 : List *newargs;
3204 116987 : bool haveNull = false;
3205 116987 : bool forceFalse = false;
3206 :
3207 116987 : newargs = simplify_and_arguments(expr->args,
3208 : context,
3209 : &haveNull,
3210 : &forceFalse);
3211 116987 : if (forceFalse)
3212 645 : return makeBoolConst(false, false);
3213 116342 : if (haveNull)
3214 25 : newargs = lappend(newargs,
3215 25 : makeBoolConst(false, true));
3216 : /* If all the inputs are TRUE, result is TRUE */
3217 116342 : if (newargs == NIL)
3218 186 : return makeBoolConst(true, false);
3219 :
3220 : /*
3221 : * If only one nonconst-or-NULL input, it's the
3222 : * result
3223 : */
3224 116156 : if (list_length(newargs) == 1)
3225 177 : return (Node *) linitial(newargs);
3226 : /* Else we still need an AND node */
3227 115979 : return (Node *) make_andclause(newargs);
3228 : }
3229 14980 : case NOT_EXPR:
3230 : {
3231 : Node *arg;
3232 :
3233 : Assert(list_length(expr->args) == 1);
3234 14980 : arg = eval_const_expressions_mutator(linitial(expr->args),
3235 : context);
3236 :
3237 : /*
3238 : * Use negate_clause() to see if we can simplify
3239 : * away the NOT.
3240 : */
3241 14980 : return negate_clause(arg);
3242 : }
3243 0 : default:
3244 0 : elog(ERROR, "unrecognized boolop: %d",
3245 : (int) expr->boolop);
3246 : break;
3247 : }
3248 : break;
3249 : }
3250 637 : case T_JsonValueExpr:
3251 : {
3252 637 : JsonValueExpr *jve = (JsonValueExpr *) node;
3253 637 : Node *raw_expr = (Node *) jve->raw_expr;
3254 637 : Node *formatted_expr = (Node *) jve->formatted_expr;
3255 :
3256 : /*
3257 : * If we can fold formatted_expr to a constant, we can elide
3258 : * the JsonValueExpr altogether. Otherwise we must process
3259 : * raw_expr too. But JsonFormat is a flat node and requires
3260 : * no simplification, only copying.
3261 : */
3262 637 : formatted_expr = eval_const_expressions_mutator(formatted_expr,
3263 : context);
3264 637 : if (formatted_expr && IsA(formatted_expr, Const))
3265 443 : return formatted_expr;
3266 :
3267 194 : raw_expr = eval_const_expressions_mutator(raw_expr, context);
3268 :
3269 194 : return (Node *) makeJsonValueExpr((Expr *) raw_expr,
3270 : (Expr *) formatted_expr,
3271 194 : copyObject(jve->format));
3272 : }
3273 1423 : case T_JsonConstructorExpr:
3274 : {
3275 1423 : JsonConstructorExpr *jce = (JsonConstructorExpr *) node;
3276 :
3277 : /*
3278 : * JSCTOR_JSON_ARRAY_QUERY carries a pre-built executable form
3279 : * in its func field (a COALESCE-wrapped JSON_ARRAYAGG
3280 : * subquery, constructed during parse analysis). Replace the
3281 : * node with that expression and continue simplifying.
3282 : */
3283 1423 : if (jce->type == JSCTOR_JSON_ARRAY_QUERY)
3284 70 : return eval_const_expressions_mutator((Node *) jce->func,
3285 : context);
3286 : }
3287 1353 : break;
3288 485 : case T_SubPlan:
3289 : case T_AlternativeSubPlan:
3290 :
3291 : /*
3292 : * Return a SubPlan unchanged --- too late to do anything with it.
3293 : *
3294 : * XXX should we ereport() here instead? Probably this routine
3295 : * should never be invoked after SubPlan creation.
3296 : */
3297 485 : return node;
3298 130427 : case T_RelabelType:
3299 : {
3300 130427 : RelabelType *relabel = (RelabelType *) node;
3301 : Node *arg;
3302 :
3303 : /* Simplify the input ... */
3304 130427 : arg = eval_const_expressions_mutator((Node *) relabel->arg,
3305 : context);
3306 : /* ... and attach a new RelabelType node, if needed */
3307 130423 : return applyRelabelType(arg,
3308 : relabel->resulttype,
3309 : relabel->resulttypmod,
3310 : relabel->resultcollid,
3311 : relabel->relabelformat,
3312 : relabel->location,
3313 : true);
3314 : }
3315 24996 : case T_CoerceViaIO:
3316 : {
3317 24996 : CoerceViaIO *expr = (CoerceViaIO *) node;
3318 : List *args;
3319 : Oid outfunc;
3320 : bool outtypisvarlena;
3321 : Oid infunc;
3322 : Oid intypioparam;
3323 : Expr *simple;
3324 : CoerceViaIO *newexpr;
3325 :
3326 : /* Make a List so we can use simplify_function */
3327 24996 : args = list_make1(expr->arg);
3328 :
3329 : /*
3330 : * CoerceViaIO represents calling the source type's output
3331 : * function then the result type's input function. So, try to
3332 : * simplify it as though it were a stack of two such function
3333 : * calls. First we need to know what the functions are.
3334 : *
3335 : * Note that the coercion functions are assumed not to care
3336 : * about input collation, so we just pass InvalidOid for that.
3337 : */
3338 24996 : getTypeOutputInfo(exprType((Node *) expr->arg),
3339 : &outfunc, &outtypisvarlena);
3340 24996 : getTypeInputInfo(expr->resulttype,
3341 : &infunc, &intypioparam);
3342 :
3343 24996 : simple = simplify_function(outfunc,
3344 : CSTRINGOID, -1,
3345 : InvalidOid,
3346 : InvalidOid,
3347 : &args,
3348 : false,
3349 : true,
3350 : true,
3351 : context);
3352 24996 : if (simple) /* successfully simplified output fn */
3353 : {
3354 : /*
3355 : * Input functions may want 1 to 3 arguments. We always
3356 : * supply all three, trusting that nothing downstream will
3357 : * complain.
3358 : */
3359 1927 : args = list_make3(simple,
3360 : makeConst(OIDOID,
3361 : -1,
3362 : InvalidOid,
3363 : sizeof(Oid),
3364 : ObjectIdGetDatum(intypioparam),
3365 : false,
3366 : true),
3367 : makeConst(INT4OID,
3368 : -1,
3369 : InvalidOid,
3370 : sizeof(int32),
3371 : Int32GetDatum(-1),
3372 : false,
3373 : true));
3374 :
3375 1927 : simple = simplify_function(infunc,
3376 : expr->resulttype, -1,
3377 : expr->resultcollid,
3378 : InvalidOid,
3379 : &args,
3380 : false,
3381 : false,
3382 : true,
3383 : context);
3384 1850 : if (simple) /* successfully simplified input fn */
3385 1787 : return (Node *) simple;
3386 : }
3387 :
3388 : /*
3389 : * The expression cannot be simplified any further, so build
3390 : * and return a replacement CoerceViaIO node using the
3391 : * possibly-simplified argument.
3392 : */
3393 23132 : newexpr = makeNode(CoerceViaIO);
3394 23132 : newexpr->arg = (Expr *) linitial(args);
3395 23132 : newexpr->resulttype = expr->resulttype;
3396 23132 : newexpr->resultcollid = expr->resultcollid;
3397 23132 : newexpr->coerceformat = expr->coerceformat;
3398 23132 : newexpr->location = expr->location;
3399 23132 : return (Node *) newexpr;
3400 : }
3401 8186 : case T_ArrayCoerceExpr:
3402 : {
3403 8186 : ArrayCoerceExpr *ac = makeNode(ArrayCoerceExpr);
3404 : Node *save_case_val;
3405 :
3406 : /*
3407 : * Copy the node and const-simplify its arguments. We can't
3408 : * use ece_generic_processing() here because we need to mess
3409 : * with case_val only while processing the elemexpr.
3410 : */
3411 8186 : memcpy(ac, node, sizeof(ArrayCoerceExpr));
3412 8186 : ac->arg = (Expr *)
3413 8186 : eval_const_expressions_mutator((Node *) ac->arg,
3414 : context);
3415 :
3416 : /*
3417 : * Set up for the CaseTestExpr node contained in the elemexpr.
3418 : * We must prevent it from absorbing any outer CASE value.
3419 : */
3420 8186 : save_case_val = context->case_val;
3421 8186 : context->case_val = NULL;
3422 :
3423 8186 : ac->elemexpr = (Expr *)
3424 8186 : eval_const_expressions_mutator((Node *) ac->elemexpr,
3425 : context);
3426 :
3427 8186 : context->case_val = save_case_val;
3428 :
3429 : /*
3430 : * If constant argument and the per-element expression is
3431 : * immutable, we can simplify the whole thing to a constant.
3432 : * Exception: although contain_mutable_functions considers
3433 : * CoerceToDomain immutable for historical reasons, let's not
3434 : * do so here; this ensures coercion to an array-over-domain
3435 : * does not apply the domain's constraints until runtime.
3436 : */
3437 8186 : if (ac->arg && IsA(ac->arg, Const) &&
3438 903 : ac->elemexpr && !IsA(ac->elemexpr, CoerceToDomain) &&
3439 883 : !contain_mutable_functions((Node *) ac->elemexpr))
3440 883 : return ece_evaluate_expr(ac);
3441 :
3442 7303 : return (Node *) ac;
3443 : }
3444 8424 : case T_CollateExpr:
3445 : {
3446 : /*
3447 : * We replace CollateExpr with RelabelType, so as to improve
3448 : * uniformity of expression representation and thus simplify
3449 : * comparison of expressions. Hence this looks very nearly
3450 : * the same as the RelabelType case, and we can apply the same
3451 : * optimizations to avoid unnecessary RelabelTypes.
3452 : */
3453 8424 : CollateExpr *collate = (CollateExpr *) node;
3454 : Node *arg;
3455 :
3456 : /* Simplify the input ... */
3457 8424 : arg = eval_const_expressions_mutator((Node *) collate->arg,
3458 : context);
3459 : /* ... and attach a new RelabelType node, if needed */
3460 8424 : return applyRelabelType(arg,
3461 : exprType(arg),
3462 : exprTypmod(arg),
3463 : collate->collOid,
3464 : COERCE_IMPLICIT_CAST,
3465 : collate->location,
3466 : true);
3467 : }
3468 28438 : case T_CaseExpr:
3469 : {
3470 : /*----------
3471 : * CASE expressions can be simplified if there are constant
3472 : * condition clauses:
3473 : * FALSE (or NULL): drop the alternative
3474 : * TRUE: drop all remaining alternatives
3475 : * If the first non-FALSE alternative is a constant TRUE,
3476 : * we can simplify the entire CASE to that alternative's
3477 : * expression. If there are no non-FALSE alternatives,
3478 : * we simplify the entire CASE to the default result (ELSE).
3479 : *
3480 : * If we have a simple-form CASE with constant test
3481 : * expression, we substitute the constant value for contained
3482 : * CaseTestExpr placeholder nodes, so that we have the
3483 : * opportunity to reduce constant test conditions. For
3484 : * example this allows
3485 : * CASE 0 WHEN 0 THEN 1 ELSE 1/0 END
3486 : * to reduce to 1 rather than drawing a divide-by-0 error.
3487 : * Note that when the test expression is constant, we don't
3488 : * have to include it in the resulting CASE; for example
3489 : * CASE 0 WHEN x THEN y ELSE z END
3490 : * is transformed by the parser to
3491 : * CASE 0 WHEN CaseTestExpr = x THEN y ELSE z END
3492 : * which we can simplify to
3493 : * CASE WHEN 0 = x THEN y ELSE z END
3494 : * It is not necessary for the executor to evaluate the "arg"
3495 : * expression when executing the CASE, since any contained
3496 : * CaseTestExprs that might have referred to it will have been
3497 : * replaced by the constant.
3498 : *----------
3499 : */
3500 28438 : CaseExpr *caseexpr = (CaseExpr *) node;
3501 : CaseExpr *newcase;
3502 : Node *save_case_val;
3503 : Node *newarg;
3504 : List *newargs;
3505 : bool const_true_cond;
3506 28438 : Node *defresult = NULL;
3507 : ListCell *arg;
3508 :
3509 : /* Simplify the test expression, if any */
3510 28438 : newarg = eval_const_expressions_mutator((Node *) caseexpr->arg,
3511 : context);
3512 :
3513 : /* Set up for contained CaseTestExpr nodes */
3514 28438 : save_case_val = context->case_val;
3515 28438 : if (newarg && IsA(newarg, Const))
3516 : {
3517 65 : context->case_val = newarg;
3518 65 : newarg = NULL; /* not needed anymore, see above */
3519 : }
3520 : else
3521 28373 : context->case_val = NULL;
3522 :
3523 : /* Simplify the WHEN clauses */
3524 28438 : newargs = NIL;
3525 28438 : const_true_cond = false;
3526 87593 : foreach(arg, caseexpr->args)
3527 : {
3528 59566 : CaseWhen *oldcasewhen = lfirst_node(CaseWhen, arg);
3529 : Node *casecond;
3530 : Node *caseresult;
3531 :
3532 : /* Simplify this alternative's test condition */
3533 59566 : casecond = eval_const_expressions_mutator((Node *) oldcasewhen->expr,
3534 : context);
3535 :
3536 : /*
3537 : * If the test condition is constant FALSE (or NULL), then
3538 : * drop this WHEN clause completely, without processing
3539 : * the result.
3540 : */
3541 59566 : if (casecond && IsA(casecond, Const))
3542 : {
3543 843 : Const *const_input = (Const *) casecond;
3544 :
3545 843 : if (const_input->constisnull ||
3546 843 : !DatumGetBool(const_input->constvalue))
3547 436 : continue; /* drop alternative with FALSE cond */
3548 : /* Else it's constant TRUE */
3549 407 : const_true_cond = true;
3550 : }
3551 :
3552 : /* Simplify this alternative's result value */
3553 59130 : caseresult = eval_const_expressions_mutator((Node *) oldcasewhen->result,
3554 : context);
3555 :
3556 : /* If non-constant test condition, emit a new WHEN node */
3557 59126 : if (!const_true_cond)
3558 58719 : {
3559 58719 : CaseWhen *newcasewhen = makeNode(CaseWhen);
3560 :
3561 58719 : newcasewhen->expr = (Expr *) casecond;
3562 58719 : newcasewhen->result = (Expr *) caseresult;
3563 58719 : newcasewhen->location = oldcasewhen->location;
3564 58719 : newargs = lappend(newargs, newcasewhen);
3565 58719 : continue;
3566 : }
3567 :
3568 : /*
3569 : * Found a TRUE condition, so none of the remaining
3570 : * alternatives can be reached. We treat the result as
3571 : * the default result.
3572 : */
3573 407 : defresult = caseresult;
3574 407 : break;
3575 : }
3576 :
3577 : /* Simplify the default result, unless we replaced it above */
3578 28434 : if (!const_true_cond)
3579 28027 : defresult = eval_const_expressions_mutator((Node *) caseexpr->defresult,
3580 : context);
3581 :
3582 28434 : context->case_val = save_case_val;
3583 :
3584 : /*
3585 : * If no non-FALSE alternatives, CASE reduces to the default
3586 : * result
3587 : */
3588 28434 : if (newargs == NIL)
3589 623 : return defresult;
3590 : /* Otherwise we need a new CASE node */
3591 27811 : newcase = makeNode(CaseExpr);
3592 27811 : newcase->casetype = caseexpr->casetype;
3593 27811 : newcase->casecollid = caseexpr->casecollid;
3594 27811 : newcase->arg = (Expr *) newarg;
3595 27811 : newcase->args = newargs;
3596 27811 : newcase->defresult = (Expr *) defresult;
3597 27811 : newcase->location = caseexpr->location;
3598 27811 : return (Node *) newcase;
3599 : }
3600 28243 : case T_CaseTestExpr:
3601 : {
3602 : /*
3603 : * If we know a constant test value for the current CASE
3604 : * construct, substitute it for the placeholder. Else just
3605 : * return the placeholder as-is.
3606 : */
3607 28243 : if (context->case_val)
3608 107 : return copyObject(context->case_val);
3609 : else
3610 28136 : return copyObject(node);
3611 : }
3612 48766 : case T_SubscriptingRef:
3613 : case T_ArrayExpr:
3614 : case T_RowExpr:
3615 : case T_MinMaxExpr:
3616 : {
3617 : /*
3618 : * Generic handling for node types whose own processing is
3619 : * known to be immutable, and for which we need no smarts
3620 : * beyond "simplify if all inputs are constants".
3621 : *
3622 : * Treating SubscriptingRef this way assumes that subscripting
3623 : * fetch and assignment are both immutable. This constrains
3624 : * type-specific subscripting implementations; maybe we should
3625 : * relax it someday.
3626 : *
3627 : * Treating MinMaxExpr this way amounts to assuming that the
3628 : * btree comparison function it calls is immutable; see the
3629 : * reasoning in contain_mutable_functions_walker.
3630 : */
3631 :
3632 : /* Copy the node and const-simplify its arguments */
3633 48766 : node = ece_generic_processing(node);
3634 : /* If all arguments are Consts, we can fold to a constant */
3635 48766 : if (ece_all_arguments_const(node))
3636 23371 : return ece_evaluate_expr(node);
3637 25395 : return node;
3638 : }
3639 2473 : case T_CoalesceExpr:
3640 : {
3641 2473 : CoalesceExpr *coalesceexpr = (CoalesceExpr *) node;
3642 : CoalesceExpr *newcoalesce;
3643 : List *newargs;
3644 : ListCell *arg;
3645 :
3646 2473 : newargs = NIL;
3647 5890 : foreach(arg, coalesceexpr->args)
3648 : {
3649 : Node *e;
3650 :
3651 4854 : e = eval_const_expressions_mutator((Node *) lfirst(arg),
3652 : context);
3653 :
3654 : /*
3655 : * We can remove null constants from the list. For a
3656 : * nonnullable expression, if it has not been preceded by
3657 : * any non-null-constant expressions then it is the
3658 : * result. Otherwise, it's the next argument, but we can
3659 : * drop following arguments since they will never be
3660 : * reached.
3661 : */
3662 4854 : if (IsA(e, Const))
3663 : {
3664 1403 : if (((Const *) e)->constisnull)
3665 46 : continue; /* drop null constant */
3666 1357 : if (newargs == NIL)
3667 133 : return e; /* first expr */
3668 1274 : newargs = lappend(newargs, e);
3669 1274 : break;
3670 : }
3671 3451 : if (expr_is_nonnullable(context->root, (Expr *) e,
3672 : NOTNULL_SOURCE_HASHTABLE))
3673 : {
3674 80 : if (newargs == NIL)
3675 50 : return e; /* first expr */
3676 30 : newargs = lappend(newargs, e);
3677 30 : break;
3678 : }
3679 :
3680 3371 : newargs = lappend(newargs, e);
3681 : }
3682 :
3683 : /*
3684 : * If all the arguments were constant null, the result is just
3685 : * null
3686 : */
3687 2340 : if (newargs == NIL)
3688 0 : return (Node *) makeNullConst(coalesceexpr->coalescetype,
3689 : -1,
3690 : coalesceexpr->coalescecollid);
3691 :
3692 : /*
3693 : * If there's exactly one surviving argument, we no longer
3694 : * need COALESCE at all: the result is that argument
3695 : */
3696 2340 : if (list_length(newargs) == 1)
3697 15 : return (Node *) linitial(newargs);
3698 :
3699 2325 : newcoalesce = makeNode(CoalesceExpr);
3700 2325 : newcoalesce->coalescetype = coalesceexpr->coalescetype;
3701 2325 : newcoalesce->coalescecollid = coalesceexpr->coalescecollid;
3702 2325 : newcoalesce->args = newargs;
3703 2325 : newcoalesce->location = coalesceexpr->location;
3704 2325 : return (Node *) newcoalesce;
3705 : }
3706 4105 : case T_SQLValueFunction:
3707 : {
3708 : /*
3709 : * All variants of SQLValueFunction are stable, so if we are
3710 : * estimating the expression's value, we should evaluate the
3711 : * current function value. Otherwise just copy.
3712 : */
3713 4105 : SQLValueFunction *svf = (SQLValueFunction *) node;
3714 :
3715 4105 : if (context->estimate)
3716 742 : return (Node *) evaluate_expr((Expr *) svf,
3717 : svf->type,
3718 : svf->typmod,
3719 : InvalidOid);
3720 : else
3721 3363 : return copyObject((Node *) svf);
3722 : }
3723 24907 : case T_FieldSelect:
3724 : {
3725 : /*
3726 : * We can optimize field selection from a whole-row Var into a
3727 : * simple Var. (This case won't be generated directly by the
3728 : * parser, because ParseComplexProjection short-circuits it.
3729 : * But it can arise while simplifying functions.) Also, we
3730 : * can optimize field selection from a RowExpr construct, or
3731 : * of course from a constant.
3732 : *
3733 : * However, replacing a whole-row Var in this way has a
3734 : * pitfall: if we've already built the rel targetlist for the
3735 : * source relation, then the whole-row Var is scheduled to be
3736 : * produced by the relation scan, but the simple Var probably
3737 : * isn't, which will lead to a failure in setrefs.c. This is
3738 : * not a problem when handling simple single-level queries, in
3739 : * which expression simplification always happens first. It
3740 : * is a risk for lateral references from subqueries, though.
3741 : * To avoid such failures, don't optimize uplevel references.
3742 : *
3743 : * We must also check that the declared type of the field is
3744 : * still the same as when the FieldSelect was created --- this
3745 : * can change if someone did ALTER COLUMN TYPE on the rowtype.
3746 : * If it isn't, we skip the optimization; the case will
3747 : * probably fail at runtime, but that's not our problem here.
3748 : */
3749 24907 : FieldSelect *fselect = (FieldSelect *) node;
3750 : FieldSelect *newfselect;
3751 : Node *arg;
3752 :
3753 24907 : arg = eval_const_expressions_mutator((Node *) fselect->arg,
3754 : context);
3755 24907 : if (arg && IsA(arg, Var) &&
3756 21928 : ((Var *) arg)->varattno == InvalidAttrNumber &&
3757 75 : ((Var *) arg)->varlevelsup == 0)
3758 : {
3759 65 : if (rowtype_field_matches(((Var *) arg)->vartype,
3760 65 : fselect->fieldnum,
3761 : fselect->resulttype,
3762 : fselect->resulttypmod,
3763 : fselect->resultcollid))
3764 : {
3765 : Var *newvar;
3766 :
3767 65 : newvar = makeVar(((Var *) arg)->varno,
3768 65 : fselect->fieldnum,
3769 : fselect->resulttype,
3770 : fselect->resulttypmod,
3771 : fselect->resultcollid,
3772 : ((Var *) arg)->varlevelsup);
3773 : /* New Var has same OLD/NEW returning as old one */
3774 65 : newvar->varreturningtype = ((Var *) arg)->varreturningtype;
3775 : /* New Var is nullable by same rels as the old one */
3776 65 : newvar->varnullingrels = ((Var *) arg)->varnullingrels;
3777 65 : return (Node *) newvar;
3778 : }
3779 : }
3780 24842 : if (arg && IsA(arg, RowExpr))
3781 : {
3782 20 : RowExpr *rowexpr = (RowExpr *) arg;
3783 :
3784 40 : if (fselect->fieldnum > 0 &&
3785 20 : fselect->fieldnum <= list_length(rowexpr->args))
3786 : {
3787 20 : Node *fld = (Node *) list_nth(rowexpr->args,
3788 20 : fselect->fieldnum - 1);
3789 :
3790 20 : if (rowtype_field_matches(rowexpr->row_typeid,
3791 20 : fselect->fieldnum,
3792 : fselect->resulttype,
3793 : fselect->resulttypmod,
3794 20 : fselect->resultcollid) &&
3795 40 : fselect->resulttype == exprType(fld) &&
3796 40 : fselect->resulttypmod == exprTypmod(fld) &&
3797 20 : fselect->resultcollid == exprCollation(fld))
3798 20 : return fld;
3799 : }
3800 : }
3801 24822 : newfselect = makeNode(FieldSelect);
3802 24822 : newfselect->arg = (Expr *) arg;
3803 24822 : newfselect->fieldnum = fselect->fieldnum;
3804 24822 : newfselect->resulttype = fselect->resulttype;
3805 24822 : newfselect->resulttypmod = fselect->resulttypmod;
3806 24822 : newfselect->resultcollid = fselect->resultcollid;
3807 24822 : if (arg && IsA(arg, Const))
3808 : {
3809 509 : Const *con = (Const *) arg;
3810 :
3811 509 : if (rowtype_field_matches(con->consttype,
3812 509 : newfselect->fieldnum,
3813 : newfselect->resulttype,
3814 : newfselect->resulttypmod,
3815 : newfselect->resultcollid))
3816 509 : return ece_evaluate_expr(newfselect);
3817 : }
3818 24313 : return (Node *) newfselect;
3819 : }
3820 28124 : case T_NullTest:
3821 : {
3822 28124 : NullTest *ntest = (NullTest *) node;
3823 : NullTest *newntest;
3824 : Node *arg;
3825 :
3826 28124 : arg = eval_const_expressions_mutator((Node *) ntest->arg,
3827 : context);
3828 28123 : if (ntest->argisrow && arg && IsA(arg, RowExpr))
3829 : {
3830 : /*
3831 : * We break ROW(...) IS [NOT] NULL into separate tests on
3832 : * its component fields. This form is usually more
3833 : * efficient to evaluate, as well as being more amenable
3834 : * to optimization.
3835 : */
3836 37 : RowExpr *rarg = (RowExpr *) arg;
3837 37 : List *newargs = NIL;
3838 : ListCell *l;
3839 :
3840 136 : foreach(l, rarg->args)
3841 : {
3842 99 : Node *relem = (Node *) lfirst(l);
3843 :
3844 : /*
3845 : * A constant field refutes the whole NullTest if it's
3846 : * of the wrong nullness; else we can discard it.
3847 : */
3848 99 : if (relem && IsA(relem, Const))
3849 0 : {
3850 0 : Const *carg = (Const *) relem;
3851 :
3852 0 : if (carg->constisnull ?
3853 0 : (ntest->nulltesttype == IS_NOT_NULL) :
3854 0 : (ntest->nulltesttype == IS_NULL))
3855 0 : return makeBoolConst(false, false);
3856 0 : continue;
3857 : }
3858 :
3859 : /*
3860 : * A proven non-nullable field refutes the whole
3861 : * NullTest if the test is IS NULL; else we can
3862 : * discard it.
3863 : */
3864 198 : if (relem &&
3865 99 : expr_is_nonnullable(context->root, (Expr *) relem,
3866 : NOTNULL_SOURCE_HASHTABLE))
3867 : {
3868 0 : if (ntest->nulltesttype == IS_NULL)
3869 0 : return makeBoolConst(false, false);
3870 0 : continue;
3871 : }
3872 :
3873 : /*
3874 : * Else, make a scalar (argisrow == false) NullTest
3875 : * for this field. Scalar semantics are required
3876 : * because IS [NOT] NULL doesn't recurse; see comments
3877 : * in ExecEvalRowNullInt().
3878 : */
3879 99 : newntest = makeNode(NullTest);
3880 99 : newntest->arg = (Expr *) relem;
3881 99 : newntest->nulltesttype = ntest->nulltesttype;
3882 99 : newntest->argisrow = false;
3883 99 : newntest->location = ntest->location;
3884 99 : newargs = lappend(newargs, newntest);
3885 : }
3886 : /* If all the inputs were constants, result is TRUE */
3887 37 : if (newargs == NIL)
3888 0 : return makeBoolConst(true, false);
3889 : /* If only one nonconst input, it's the result */
3890 37 : if (list_length(newargs) == 1)
3891 0 : return (Node *) linitial(newargs);
3892 : /* Else we need an AND node */
3893 37 : return (Node *) make_andclause(newargs);
3894 : }
3895 28086 : if (!ntest->argisrow && arg && IsA(arg, Const))
3896 : {
3897 281 : Const *carg = (Const *) arg;
3898 : bool result;
3899 :
3900 281 : switch (ntest->nulltesttype)
3901 : {
3902 238 : case IS_NULL:
3903 238 : result = carg->constisnull;
3904 238 : break;
3905 43 : case IS_NOT_NULL:
3906 43 : result = !carg->constisnull;
3907 43 : break;
3908 0 : default:
3909 0 : elog(ERROR, "unrecognized nulltesttype: %d",
3910 : (int) ntest->nulltesttype);
3911 : result = false; /* keep compiler quiet */
3912 : break;
3913 : }
3914 :
3915 281 : return makeBoolConst(result, false);
3916 : }
3917 55268 : if (!ntest->argisrow && arg &&
3918 27463 : expr_is_nonnullable(context->root, (Expr *) arg,
3919 : NOTNULL_SOURCE_HASHTABLE))
3920 : {
3921 : bool result;
3922 :
3923 536 : switch (ntest->nulltesttype)
3924 : {
3925 128 : case IS_NULL:
3926 128 : result = false;
3927 128 : break;
3928 408 : case IS_NOT_NULL:
3929 408 : result = true;
3930 408 : break;
3931 0 : default:
3932 0 : elog(ERROR, "unrecognized nulltesttype: %d",
3933 : (int) ntest->nulltesttype);
3934 : result = false; /* keep compiler quiet */
3935 : break;
3936 : }
3937 :
3938 536 : return makeBoolConst(result, false);
3939 : }
3940 :
3941 27269 : newntest = makeNode(NullTest);
3942 27269 : newntest->arg = (Expr *) arg;
3943 27269 : newntest->nulltesttype = ntest->nulltesttype;
3944 27269 : newntest->argisrow = ntest->argisrow;
3945 27269 : newntest->location = ntest->location;
3946 27269 : return (Node *) newntest;
3947 : }
3948 1684 : case T_BooleanTest:
3949 : {
3950 : /*
3951 : * This case could be folded into the generic handling used
3952 : * for ArrayExpr etc. But because the simplification logic is
3953 : * so trivial, applying evaluate_expr() to perform it would be
3954 : * a heavy overhead. BooleanTest is probably common enough to
3955 : * justify keeping this bespoke implementation.
3956 : */
3957 1684 : BooleanTest *btest = (BooleanTest *) node;
3958 : BooleanTest *newbtest;
3959 : Node *arg;
3960 :
3961 1684 : arg = eval_const_expressions_mutator((Node *) btest->arg,
3962 : context);
3963 1684 : if (arg && IsA(arg, Const))
3964 : {
3965 : /*
3966 : * If arg is Const, simplify to constant.
3967 : */
3968 195 : Const *carg = (Const *) arg;
3969 : bool result;
3970 :
3971 195 : switch (btest->booltesttype)
3972 : {
3973 0 : case IS_TRUE:
3974 0 : result = (!carg->constisnull &&
3975 0 : DatumGetBool(carg->constvalue));
3976 0 : break;
3977 195 : case IS_NOT_TRUE:
3978 390 : result = (carg->constisnull ||
3979 195 : !DatumGetBool(carg->constvalue));
3980 195 : break;
3981 0 : case IS_FALSE:
3982 0 : result = (!carg->constisnull &&
3983 0 : !DatumGetBool(carg->constvalue));
3984 0 : break;
3985 0 : case IS_NOT_FALSE:
3986 0 : result = (carg->constisnull ||
3987 0 : DatumGetBool(carg->constvalue));
3988 0 : break;
3989 0 : case IS_UNKNOWN:
3990 0 : result = carg->constisnull;
3991 0 : break;
3992 0 : case IS_NOT_UNKNOWN:
3993 0 : result = !carg->constisnull;
3994 0 : break;
3995 0 : default:
3996 0 : elog(ERROR, "unrecognized booltesttype: %d",
3997 : (int) btest->booltesttype);
3998 : result = false; /* keep compiler quiet */
3999 : break;
4000 : }
4001 :
4002 195 : return makeBoolConst(result, false);
4003 : }
4004 2978 : if (arg &&
4005 1489 : expr_is_nonnullable(context->root, (Expr *) arg,
4006 : NOTNULL_SOURCE_HASHTABLE))
4007 : {
4008 : /*
4009 : * If arg is proven non-nullable, simplify to boolean
4010 : * expression or constant.
4011 : */
4012 62 : switch (btest->booltesttype)
4013 : {
4014 20 : case IS_TRUE:
4015 : case IS_NOT_FALSE:
4016 20 : return arg;
4017 :
4018 22 : case IS_FALSE:
4019 : case IS_NOT_TRUE:
4020 22 : return (Node *) make_notclause((Expr *) arg);
4021 :
4022 10 : case IS_UNKNOWN:
4023 10 : return makeBoolConst(false, false);
4024 :
4025 10 : case IS_NOT_UNKNOWN:
4026 10 : return makeBoolConst(true, false);
4027 :
4028 0 : default:
4029 0 : elog(ERROR, "unrecognized booltesttype: %d",
4030 : (int) btest->booltesttype);
4031 : break;
4032 : }
4033 : }
4034 :
4035 1427 : newbtest = makeNode(BooleanTest);
4036 1427 : newbtest->arg = (Expr *) arg;
4037 1427 : newbtest->booltesttype = btest->booltesttype;
4038 1427 : newbtest->location = btest->location;
4039 1427 : return (Node *) newbtest;
4040 : }
4041 18449 : case T_CoerceToDomain:
4042 : {
4043 : /*
4044 : * If the domain currently has no constraints, we replace the
4045 : * CoerceToDomain node with a simple RelabelType, which is
4046 : * both far faster to execute and more amenable to later
4047 : * optimization. We must then mark the plan as needing to be
4048 : * rebuilt if the domain's constraints change.
4049 : *
4050 : * Also, in estimation mode, always replace CoerceToDomain
4051 : * nodes, effectively assuming that the coercion will succeed.
4052 : */
4053 18449 : CoerceToDomain *cdomain = (CoerceToDomain *) node;
4054 : CoerceToDomain *newcdomain;
4055 : Node *arg;
4056 :
4057 18449 : arg = eval_const_expressions_mutator((Node *) cdomain->arg,
4058 : context);
4059 18429 : if (context->estimate ||
4060 18389 : !DomainHasConstraints(cdomain->resulttype, NULL))
4061 : {
4062 : /* Record dependency, if this isn't estimation mode */
4063 12273 : if (context->root && !context->estimate)
4064 12189 : record_plan_type_dependency(context->root,
4065 : cdomain->resulttype);
4066 :
4067 : /* Generate RelabelType to substitute for CoerceToDomain */
4068 12273 : return applyRelabelType(arg,
4069 : cdomain->resulttype,
4070 : cdomain->resulttypmod,
4071 : cdomain->resultcollid,
4072 : cdomain->coercionformat,
4073 : cdomain->location,
4074 : true);
4075 : }
4076 :
4077 6156 : newcdomain = makeNode(CoerceToDomain);
4078 6156 : newcdomain->arg = (Expr *) arg;
4079 6156 : newcdomain->resulttype = cdomain->resulttype;
4080 6156 : newcdomain->resulttypmod = cdomain->resulttypmod;
4081 6156 : newcdomain->resultcollid = cdomain->resultcollid;
4082 6156 : newcdomain->coercionformat = cdomain->coercionformat;
4083 6156 : newcdomain->location = cdomain->location;
4084 6156 : return (Node *) newcdomain;
4085 : }
4086 3907 : case T_PlaceHolderVar:
4087 :
4088 : /*
4089 : * In estimation mode, just strip the PlaceHolderVar node
4090 : * altogether; this amounts to estimating that the contained value
4091 : * won't be forced to null by an outer join. In regular mode we
4092 : * just use the default behavior (ie, simplify the expression but
4093 : * leave the PlaceHolderVar node intact).
4094 : */
4095 3907 : if (context->estimate)
4096 : {
4097 710 : PlaceHolderVar *phv = (PlaceHolderVar *) node;
4098 :
4099 710 : return eval_const_expressions_mutator((Node *) phv->phexpr,
4100 : context);
4101 : }
4102 3197 : break;
4103 75 : case T_ConvertRowtypeExpr:
4104 : {
4105 75 : ConvertRowtypeExpr *cre = castNode(ConvertRowtypeExpr, node);
4106 : Node *arg;
4107 : ConvertRowtypeExpr *newcre;
4108 :
4109 75 : arg = eval_const_expressions_mutator((Node *) cre->arg,
4110 : context);
4111 :
4112 75 : newcre = makeNode(ConvertRowtypeExpr);
4113 75 : newcre->resulttype = cre->resulttype;
4114 75 : newcre->convertformat = cre->convertformat;
4115 75 : newcre->location = cre->location;
4116 :
4117 : /*
4118 : * In case of a nested ConvertRowtypeExpr, we can convert the
4119 : * leaf row directly to the topmost row format without any
4120 : * intermediate conversions. (This works because
4121 : * ConvertRowtypeExpr is used only for child->parent
4122 : * conversion in inheritance trees, which works by exact match
4123 : * of column name, and a column absent in an intermediate
4124 : * result can't be present in the final result.)
4125 : *
4126 : * No need to check more than one level deep, because the
4127 : * above recursion will have flattened anything else.
4128 : */
4129 75 : if (arg != NULL && IsA(arg, ConvertRowtypeExpr))
4130 : {
4131 10 : ConvertRowtypeExpr *argcre = (ConvertRowtypeExpr *) arg;
4132 :
4133 10 : arg = (Node *) argcre->arg;
4134 :
4135 : /*
4136 : * Make sure an outer implicit conversion can't hide an
4137 : * inner explicit one.
4138 : */
4139 10 : if (newcre->convertformat == COERCE_IMPLICIT_CAST)
4140 0 : newcre->convertformat = argcre->convertformat;
4141 : }
4142 :
4143 75 : newcre->arg = (Expr *) arg;
4144 :
4145 75 : if (arg != NULL && IsA(arg, Const))
4146 15 : return ece_evaluate_expr((Node *) newcre);
4147 60 : return (Node *) newcre;
4148 : }
4149 5223355 : default:
4150 5223355 : break;
4151 : }
4152 :
4153 : /*
4154 : * For any node type not handled above, copy the node unchanged but
4155 : * const-simplify its subexpressions. This is the correct thing for node
4156 : * types whose behavior might change between planning and execution, such
4157 : * as CurrentOfExpr. It's also a safe default for new node types not
4158 : * known to this routine.
4159 : */
4160 5227905 : return ece_generic_processing(node);
4161 : }
4162 :
4163 : /*
4164 : * Subroutine for eval_const_expressions: check for non-Const nodes.
4165 : *
4166 : * We can abort recursion immediately on finding a non-Const node. This is
4167 : * critical for performance, else eval_const_expressions_mutator would take
4168 : * O(N^2) time on non-simplifiable trees. However, we do need to descend
4169 : * into List nodes since expression_tree_walker sometimes invokes the walker
4170 : * function directly on List subtrees.
4171 : */
4172 : static bool
4173 168410 : contain_non_const_walker(Node *node, void *context)
4174 : {
4175 168410 : if (node == NULL)
4176 596 : return false;
4177 167814 : if (IsA(node, Const))
4178 86684 : return false;
4179 81130 : if (IsA(node, List))
4180 26620 : return expression_tree_walker(node, contain_non_const_walker, context);
4181 : /* Otherwise, abort the tree traversal and return true */
4182 54510 : return true;
4183 : }
4184 :
4185 : /*
4186 : * Subroutine for eval_const_expressions: check if a function is OK to evaluate
4187 : */
4188 : static bool
4189 300 : ece_function_is_safe(Oid funcid, eval_const_expressions_context *context)
4190 : {
4191 300 : char provolatile = func_volatile(funcid);
4192 :
4193 : /*
4194 : * Ordinarily we are only allowed to simplify immutable functions. But for
4195 : * purposes of estimation, we consider it okay to simplify functions that
4196 : * are merely stable; the risk that the result might change from planning
4197 : * time to execution time is worth taking in preference to not being able
4198 : * to estimate the value at all.
4199 : */
4200 300 : if (provolatile == PROVOLATILE_IMMUTABLE)
4201 300 : return true;
4202 0 : if (context->estimate && provolatile == PROVOLATILE_STABLE)
4203 0 : return true;
4204 0 : return false;
4205 : }
4206 :
4207 : /*
4208 : * Subroutine for eval_const_expressions: process arguments of an OR clause
4209 : *
4210 : * This includes flattening of nested ORs as well as recursion to
4211 : * eval_const_expressions to simplify the OR arguments.
4212 : *
4213 : * After simplification, OR arguments are handled as follows:
4214 : * non constant: keep
4215 : * FALSE: drop (does not affect result)
4216 : * TRUE: force result to TRUE
4217 : * NULL: keep only one
4218 : * We must keep one NULL input because OR expressions evaluate to NULL when no
4219 : * input is TRUE and at least one is NULL. We don't actually include the NULL
4220 : * here, that's supposed to be done by the caller.
4221 : *
4222 : * The output arguments *haveNull and *forceTrue must be initialized false
4223 : * by the caller. They will be set true if a NULL constant or TRUE constant,
4224 : * respectively, is detected anywhere in the argument list.
4225 : */
4226 : static List *
4227 15354 : simplify_or_arguments(List *args,
4228 : eval_const_expressions_context *context,
4229 : bool *haveNull, bool *forceTrue)
4230 : {
4231 15354 : List *newargs = NIL;
4232 : List *unprocessed_args;
4233 :
4234 : /*
4235 : * We want to ensure that any OR immediately beneath another OR gets
4236 : * flattened into a single OR-list, so as to simplify later reasoning.
4237 : *
4238 : * To avoid stack overflow from recursion of eval_const_expressions, we
4239 : * resort to some tenseness here: we keep a list of not-yet-processed
4240 : * inputs, and handle flattening of nested ORs by prepending to the to-do
4241 : * list instead of recursing. Now that the parser generates N-argument
4242 : * ORs from simple lists, this complexity is probably less necessary than
4243 : * it once was, but we might as well keep the logic.
4244 : */
4245 15354 : unprocessed_args = list_copy(args);
4246 49760 : while (unprocessed_args)
4247 : {
4248 34512 : Node *arg = (Node *) linitial(unprocessed_args);
4249 :
4250 34512 : unprocessed_args = list_delete_first(unprocessed_args);
4251 :
4252 : /* flatten nested ORs as per above comment */
4253 34512 : if (is_orclause(arg))
4254 7 : {
4255 7 : List *subargs = ((BoolExpr *) arg)->args;
4256 7 : List *oldlist = unprocessed_args;
4257 :
4258 7 : unprocessed_args = list_concat_copy(subargs, unprocessed_args);
4259 : /* perhaps-overly-tense code to avoid leaking old lists */
4260 7 : list_free(oldlist);
4261 7 : continue;
4262 : }
4263 :
4264 : /* If it's not an OR, simplify it */
4265 34505 : arg = eval_const_expressions_mutator(arg, context);
4266 :
4267 : /*
4268 : * It is unlikely but not impossible for simplification of a non-OR
4269 : * clause to produce an OR. Recheck, but don't be too tense about it
4270 : * since it's not a mainstream case. In particular we don't worry
4271 : * about const-simplifying the input twice, nor about list leakage.
4272 : */
4273 34505 : if (is_orclause(arg))
4274 0 : {
4275 0 : List *subargs = ((BoolExpr *) arg)->args;
4276 :
4277 0 : unprocessed_args = list_concat_copy(subargs, unprocessed_args);
4278 0 : continue;
4279 : }
4280 :
4281 : /*
4282 : * OK, we have a const-simplified non-OR argument. Process it per
4283 : * comments above.
4284 : */
4285 34505 : if (IsA(arg, Const))
4286 3949 : {
4287 4055 : Const *const_input = (Const *) arg;
4288 :
4289 4055 : if (const_input->constisnull)
4290 3813 : *haveNull = true;
4291 242 : else if (DatumGetBool(const_input->constvalue))
4292 : {
4293 106 : *forceTrue = true;
4294 :
4295 : /*
4296 : * Once we detect a TRUE result we can just exit the loop
4297 : * immediately. However, if we ever add a notion of
4298 : * non-removable functions, we'd need to keep scanning.
4299 : */
4300 106 : return NIL;
4301 : }
4302 : /* otherwise, we can drop the constant-false input */
4303 3949 : continue;
4304 : }
4305 :
4306 : /* else emit the simplified arg into the result list */
4307 30450 : newargs = lappend(newargs, arg);
4308 : }
4309 :
4310 15248 : return newargs;
4311 : }
4312 :
4313 : /*
4314 : * Subroutine for eval_const_expressions: process arguments of an AND clause
4315 : *
4316 : * This includes flattening of nested ANDs as well as recursion to
4317 : * eval_const_expressions to simplify the AND arguments.
4318 : *
4319 : * After simplification, AND arguments are handled as follows:
4320 : * non constant: keep
4321 : * TRUE: drop (does not affect result)
4322 : * FALSE: force result to FALSE
4323 : * NULL: keep only one
4324 : * We must keep one NULL input because AND expressions evaluate to NULL when
4325 : * no input is FALSE and at least one is NULL. We don't actually include the
4326 : * NULL here, that's supposed to be done by the caller.
4327 : *
4328 : * The output arguments *haveNull and *forceFalse must be initialized false
4329 : * by the caller. They will be set true if a null constant or false constant,
4330 : * respectively, is detected anywhere in the argument list.
4331 : */
4332 : static List *
4333 116987 : simplify_and_arguments(List *args,
4334 : eval_const_expressions_context *context,
4335 : bool *haveNull, bool *forceFalse)
4336 : {
4337 116987 : List *newargs = NIL;
4338 : List *unprocessed_args;
4339 :
4340 : /* See comments in simplify_or_arguments */
4341 116987 : unprocessed_args = list_copy(args);
4342 425485 : while (unprocessed_args)
4343 : {
4344 309143 : Node *arg = (Node *) linitial(unprocessed_args);
4345 :
4346 309143 : unprocessed_args = list_delete_first(unprocessed_args);
4347 :
4348 : /* flatten nested ANDs as per above comment */
4349 309143 : if (is_andclause(arg))
4350 4120 : {
4351 4120 : List *subargs = ((BoolExpr *) arg)->args;
4352 4120 : List *oldlist = unprocessed_args;
4353 :
4354 4120 : unprocessed_args = list_concat_copy(subargs, unprocessed_args);
4355 : /* perhaps-overly-tense code to avoid leaking old lists */
4356 4120 : list_free(oldlist);
4357 4120 : continue;
4358 : }
4359 :
4360 : /* If it's not an AND, simplify it */
4361 305023 : arg = eval_const_expressions_mutator(arg, context);
4362 :
4363 : /*
4364 : * It is unlikely but not impossible for simplification of a non-AND
4365 : * clause to produce an AND. Recheck, but don't be too tense about it
4366 : * since it's not a mainstream case. In particular we don't worry
4367 : * about const-simplifying the input twice, nor about list leakage.
4368 : */
4369 305023 : if (is_andclause(arg))
4370 30 : {
4371 30 : List *subargs = ((BoolExpr *) arg)->args;
4372 :
4373 30 : unprocessed_args = list_concat_copy(subargs, unprocessed_args);
4374 30 : continue;
4375 : }
4376 :
4377 : /*
4378 : * OK, we have a const-simplified non-AND argument. Process it per
4379 : * comments above.
4380 : */
4381 304993 : if (IsA(arg, Const))
4382 1238 : {
4383 1883 : Const *const_input = (Const *) arg;
4384 :
4385 1883 : if (const_input->constisnull)
4386 35 : *haveNull = true;
4387 1848 : else if (!DatumGetBool(const_input->constvalue))
4388 : {
4389 645 : *forceFalse = true;
4390 :
4391 : /*
4392 : * Once we detect a FALSE result we can just exit the loop
4393 : * immediately. However, if we ever add a notion of
4394 : * non-removable functions, we'd need to keep scanning.
4395 : */
4396 645 : return NIL;
4397 : }
4398 : /* otherwise, we can drop the constant-true input */
4399 1238 : continue;
4400 : }
4401 :
4402 : /* else emit the simplified arg into the result list */
4403 303110 : newargs = lappend(newargs, arg);
4404 : }
4405 :
4406 116342 : return newargs;
4407 : }
4408 :
4409 : /*
4410 : * Subroutine for eval_const_expressions: try to simplify boolean equality
4411 : * or inequality condition
4412 : *
4413 : * Inputs are the operator OID and the simplified arguments to the operator.
4414 : * Returns a simplified expression if successful, or NULL if cannot
4415 : * simplify the expression.
4416 : *
4417 : * The idea here is to reduce "x = true" to "x" and "x = false" to "NOT x",
4418 : * or similarly "x <> true" to "NOT x" and "x <> false" to "x".
4419 : * This is only marginally useful in itself, but doing it in constant folding
4420 : * ensures that we will recognize these forms as being equivalent in, for
4421 : * example, partial index matching.
4422 : *
4423 : * We come here only if simplify_function has failed; therefore we cannot
4424 : * see two constant inputs, nor a constant-NULL input.
4425 : */
4426 : static Node *
4427 1796 : simplify_boolean_equality(Oid opno, List *args)
4428 : {
4429 : Node *leftop;
4430 : Node *rightop;
4431 :
4432 : Assert(list_length(args) == 2);
4433 1796 : leftop = linitial(args);
4434 1796 : rightop = lsecond(args);
4435 1796 : if (leftop && IsA(leftop, Const))
4436 : {
4437 : Assert(!((Const *) leftop)->constisnull);
4438 0 : if (opno == BooleanEqualOperator)
4439 : {
4440 0 : if (DatumGetBool(((Const *) leftop)->constvalue))
4441 0 : return rightop; /* true = foo */
4442 : else
4443 0 : return negate_clause(rightop); /* false = foo */
4444 : }
4445 : else
4446 : {
4447 0 : if (DatumGetBool(((Const *) leftop)->constvalue))
4448 0 : return negate_clause(rightop); /* true <> foo */
4449 : else
4450 0 : return rightop; /* false <> foo */
4451 : }
4452 : }
4453 1796 : if (rightop && IsA(rightop, Const))
4454 : {
4455 : Assert(!((Const *) rightop)->constisnull);
4456 1311 : if (opno == BooleanEqualOperator)
4457 : {
4458 1256 : if (DatumGetBool(((Const *) rightop)->constvalue))
4459 184 : return leftop; /* foo = true */
4460 : else
4461 1072 : return negate_clause(leftop); /* foo = false */
4462 : }
4463 : else
4464 : {
4465 55 : if (DatumGetBool(((Const *) rightop)->constvalue))
4466 50 : return negate_clause(leftop); /* foo <> true */
4467 : else
4468 5 : return leftop; /* foo <> false */
4469 : }
4470 : }
4471 485 : return NULL;
4472 : }
4473 :
4474 : /*
4475 : * Subroutine for eval_const_expressions: try to simplify a function call
4476 : * (which might originally have been an operator; we don't care)
4477 : *
4478 : * Inputs are the function OID, actual result type OID (which is needed for
4479 : * polymorphic functions), result typmod, result collation, the input
4480 : * collation to use for the function, the original argument list (not
4481 : * const-simplified yet, unless process_args is false), and some flags;
4482 : * also the context data for eval_const_expressions.
4483 : *
4484 : * Returns a simplified expression if successful, or NULL if cannot
4485 : * simplify the function call.
4486 : *
4487 : * This function is also responsible for converting named-notation argument
4488 : * lists into positional notation and/or adding any needed default argument
4489 : * expressions; which is a bit grotty, but it avoids extra fetches of the
4490 : * function's pg_proc tuple. For this reason, the args list is
4491 : * pass-by-reference. Conversion and const-simplification of the args list
4492 : * will be done even if simplification of the function call itself is not
4493 : * possible.
4494 : */
4495 : static Expr *
4496 967630 : simplify_function(Oid funcid, Oid result_type, int32 result_typmod,
4497 : Oid result_collid, Oid input_collid, List **args_p,
4498 : bool funcvariadic, bool process_args, bool allow_non_const,
4499 : eval_const_expressions_context *context)
4500 : {
4501 967630 : List *args = *args_p;
4502 : HeapTuple func_tuple;
4503 : Form_pg_proc func_form;
4504 : Expr *newexpr;
4505 :
4506 : /*
4507 : * We have three strategies for simplification: execute the function to
4508 : * deliver a constant result, use a transform function to generate a
4509 : * substitute node tree, or expand in-line the body of the function
4510 : * definition (which only works for simple SQL-language functions, but
4511 : * that is a common case). Each case needs access to the function's
4512 : * pg_proc tuple, so fetch it just once.
4513 : *
4514 : * Note: the allow_non_const flag suppresses both the second and third
4515 : * strategies; so if !allow_non_const, simplify_function can only return a
4516 : * Const or NULL. Argument-list rewriting happens anyway, though.
4517 : */
4518 967630 : func_tuple = SearchSysCache1(PROCOID, ObjectIdGetDatum(funcid));
4519 967630 : if (!HeapTupleIsValid(func_tuple))
4520 0 : elog(ERROR, "cache lookup failed for function %u", funcid);
4521 967630 : func_form = (Form_pg_proc) GETSTRUCT(func_tuple);
4522 :
4523 : /*
4524 : * Process the function arguments, unless the caller did it already.
4525 : *
4526 : * Here we must deal with named or defaulted arguments, and then
4527 : * recursively apply eval_const_expressions to the whole argument list.
4528 : */
4529 967630 : if (process_args)
4530 : {
4531 965683 : args = expand_function_arguments(args, false, result_type, func_tuple);
4532 965683 : args = (List *) expression_tree_mutator((Node *) args,
4533 : eval_const_expressions_mutator,
4534 : context);
4535 : /* Argument processing done, give it back to the caller */
4536 965606 : *args_p = args;
4537 : }
4538 :
4539 : /* Now attempt simplification of the function call proper. */
4540 :
4541 967553 : newexpr = evaluate_function(funcid, result_type, result_typmod,
4542 : result_collid, input_collid,
4543 : args, funcvariadic,
4544 : func_tuple, context);
4545 :
4546 964912 : if (!newexpr && allow_non_const && OidIsValid(func_form->prosupport))
4547 : {
4548 : /*
4549 : * Build a SupportRequestSimplify node to pass to the support
4550 : * function, pointing to a dummy FuncExpr node containing the
4551 : * simplified arg list. We use this approach to present a uniform
4552 : * interface to the support function regardless of how the target
4553 : * function is actually being invoked.
4554 : */
4555 : SupportRequestSimplify req;
4556 : FuncExpr fexpr;
4557 :
4558 27173 : fexpr.xpr.type = T_FuncExpr;
4559 27173 : fexpr.funcid = funcid;
4560 27173 : fexpr.funcresulttype = result_type;
4561 27173 : fexpr.funcretset = func_form->proretset;
4562 27173 : fexpr.funcvariadic = funcvariadic;
4563 27173 : fexpr.funcformat = COERCE_EXPLICIT_CALL;
4564 27173 : fexpr.funccollid = result_collid;
4565 27173 : fexpr.inputcollid = input_collid;
4566 27173 : fexpr.args = args;
4567 27173 : fexpr.location = -1;
4568 :
4569 27173 : req.type = T_SupportRequestSimplify;
4570 27173 : req.root = context->root;
4571 27173 : req.fcall = &fexpr;
4572 :
4573 : newexpr = (Expr *)
4574 27173 : DatumGetPointer(OidFunctionCall1(func_form->prosupport,
4575 : PointerGetDatum(&req)));
4576 :
4577 : /* catch a possible API misunderstanding */
4578 : Assert(newexpr != (Expr *) &fexpr);
4579 : }
4580 :
4581 964912 : if (!newexpr && allow_non_const)
4582 832127 : newexpr = inline_function(funcid, result_type, result_collid,
4583 : input_collid, args, funcvariadic,
4584 : func_tuple, context);
4585 :
4586 964903 : ReleaseSysCache(func_tuple);
4587 :
4588 964903 : return newexpr;
4589 : }
4590 :
4591 : /*
4592 : * simplify_aggref
4593 : * Call the Aggref.aggfnoid's prosupport function to allow it to
4594 : * determine if simplification of the Aggref is possible. Returns the
4595 : * newly simplified node if conversion took place; otherwise, returns the
4596 : * original Aggref.
4597 : *
4598 : * See SupportRequestSimplifyAggref comments in supportnodes.h for further
4599 : * details.
4600 : */
4601 : static Node *
4602 38275 : simplify_aggref(Aggref *aggref, eval_const_expressions_context *context)
4603 : {
4604 38275 : Oid prosupport = get_func_support(aggref->aggfnoid);
4605 :
4606 38275 : if (OidIsValid(prosupport))
4607 : {
4608 : SupportRequestSimplifyAggref req;
4609 : Node *newnode;
4610 :
4611 : /*
4612 : * Build a SupportRequestSimplifyAggref node to pass to the support
4613 : * function.
4614 : */
4615 14118 : req.type = T_SupportRequestSimplifyAggref;
4616 14118 : req.root = context->root;
4617 14118 : req.aggref = aggref;
4618 :
4619 14118 : newnode = (Node *) DatumGetPointer(OidFunctionCall1(prosupport,
4620 : PointerGetDatum(&req)));
4621 :
4622 : /*
4623 : * We expect the support function to return either a new Node or NULL
4624 : * (when simplification isn't possible).
4625 : */
4626 : Assert(newnode != (Node *) aggref || newnode == NULL);
4627 :
4628 14118 : if (newnode != NULL)
4629 303 : return newnode;
4630 : }
4631 :
4632 37972 : return (Node *) aggref;
4633 : }
4634 :
4635 : /*
4636 : * var_is_nonnullable: check to see if the Var cannot be NULL
4637 : *
4638 : * If the Var is defined NOT NULL and meanwhile is not nulled by any outer
4639 : * joins or grouping sets, then we can know that it cannot be NULL.
4640 : *
4641 : * "source" specifies where we should look for NOT NULL proofs.
4642 : */
4643 : bool
4644 25620 : var_is_nonnullable(PlannerInfo *root, Var *var, NotNullSource source)
4645 : {
4646 : Assert(IsA(var, Var));
4647 :
4648 : /* skip upper-level Vars */
4649 25620 : if (var->varlevelsup != 0)
4650 55 : return false;
4651 :
4652 : /* could the Var be nulled by any outer joins or grouping sets? */
4653 25565 : if (!bms_is_empty(var->varnullingrels))
4654 3596 : return false;
4655 :
4656 : /*
4657 : * If the Var has a non-default returning type, it could be NULL
4658 : * regardless of any NOT NULL constraint. For example, OLD.col is NULL
4659 : * for INSERT, and NEW.col is NULL for DELETE.
4660 : */
4661 21969 : if (var->varreturningtype != VAR_RETURNING_DEFAULT)
4662 20 : return false;
4663 :
4664 : /* system columns cannot be NULL */
4665 21949 : if (var->varattno < 0)
4666 30 : return true;
4667 :
4668 : /* we don't trust whole-row Vars */
4669 21919 : if (var->varattno == 0)
4670 48 : return false;
4671 :
4672 : /* Check if the Var is defined as NOT NULL. */
4673 21871 : switch (source)
4674 : {
4675 6280 : case NOTNULL_SOURCE_RELOPT:
4676 : {
4677 : /*
4678 : * We retrieve the column NOT NULL constraint information from
4679 : * the corresponding RelOptInfo.
4680 : */
4681 : RelOptInfo *rel;
4682 : Bitmapset *notnullattnums;
4683 :
4684 6280 : rel = find_base_rel(root, var->varno);
4685 6280 : notnullattnums = rel->notnullattnums;
4686 :
4687 6280 : return bms_is_member(var->varattno, notnullattnums);
4688 : }
4689 15476 : case NOTNULL_SOURCE_HASHTABLE:
4690 : {
4691 : /*
4692 : * We retrieve the column NOT NULL constraint information from
4693 : * the hash table.
4694 : */
4695 : RangeTblEntry *rte;
4696 : Bitmapset *notnullattnums;
4697 :
4698 15476 : rte = planner_rt_fetch(var->varno, root);
4699 :
4700 : /* We can only reason about ordinary relations */
4701 15476 : if (rte->rtekind != RTE_RELATION)
4702 1392 : return false;
4703 :
4704 : /*
4705 : * We must skip inheritance parent tables, as some child
4706 : * tables may have a NOT NULL constraint for a column while
4707 : * others may not. This cannot happen with partitioned
4708 : * tables, though.
4709 : */
4710 14084 : if (rte->inh && rte->relkind != RELKIND_PARTITIONED_TABLE)
4711 175 : return false;
4712 :
4713 13909 : notnullattnums = find_relation_notnullatts(root, rte->relid);
4714 :
4715 13909 : return bms_is_member(var->varattno, notnullattnums);
4716 : }
4717 115 : case NOTNULL_SOURCE_CATALOG:
4718 : {
4719 : /*
4720 : * We check the attnullability field in the tuple descriptor.
4721 : * This is necessary rather than checking the attnotnull field
4722 : * from the attribute relation, because attnotnull is also set
4723 : * for invalid (NOT VALID) NOT NULL constraints, which do not
4724 : * guarantee the absence of NULLs.
4725 : */
4726 : RangeTblEntry *rte;
4727 : Relation rel;
4728 : CompactAttribute *attr;
4729 : bool result;
4730 :
4731 115 : rte = planner_rt_fetch(var->varno, root);
4732 :
4733 : /* We can only reason about ordinary relations */
4734 115 : if (rte->rtekind != RTE_RELATION)
4735 0 : return false;
4736 :
4737 : /*
4738 : * We must skip inheritance parent tables, as some child
4739 : * tables may have a NOT NULL constraint for a column while
4740 : * others may not. This cannot happen with partitioned
4741 : * tables, though.
4742 : *
4743 : * Note that we need to check if the relation actually has any
4744 : * children, as we might not have done that yet.
4745 : */
4746 115 : if (rte->inh && has_subclass(rte->relid) &&
4747 0 : rte->relkind != RELKIND_PARTITIONED_TABLE)
4748 0 : return false;
4749 :
4750 : /* We need not lock the relation since it was already locked */
4751 115 : rel = table_open(rte->relid, NoLock);
4752 115 : attr = TupleDescCompactAttr(RelationGetDescr(rel),
4753 115 : var->varattno - 1);
4754 115 : result = (attr->attnullability == ATTNULLABLE_VALID);
4755 115 : table_close(rel, NoLock);
4756 :
4757 115 : return result;
4758 : }
4759 0 : default:
4760 0 : elog(ERROR, "unrecognized NotNullSource: %d",
4761 : (int) source);
4762 : break;
4763 : }
4764 :
4765 : return false;
4766 : }
4767 :
4768 : /*
4769 : * expr_is_nonnullable: check to see if the Expr cannot be NULL
4770 : *
4771 : * Returns true iff the given 'expr' cannot produce SQL NULLs.
4772 : *
4773 : * source: specifies where we should look for NOT NULL proofs for Vars.
4774 : * - NOTNULL_SOURCE_RELOPT: Used when RelOptInfos have been generated. We
4775 : * retrieve nullability information directly from the RelOptInfo corresponding
4776 : * to the Var.
4777 : * - NOTNULL_SOURCE_HASHTABLE: Used when RelOptInfos are not yet available,
4778 : * but we have already collected relation-level not-null constraints into the
4779 : * global hash table.
4780 : * - NOTNULL_SOURCE_CATALOG: Used for raw parse trees where neither
4781 : * RelOptInfos nor the hash table are available. In this case, we check the
4782 : * column's attnullability in the tuple descriptor.
4783 : *
4784 : * For now, we support only a limited set of expression types. Support for
4785 : * additional node types can be added in the future.
4786 : */
4787 : bool
4788 42487 : expr_is_nonnullable(PlannerInfo *root, Expr *expr, NotNullSource source)
4789 : {
4790 : /* since this function recurses, it could be driven to stack overflow */
4791 42487 : check_stack_depth();
4792 :
4793 42487 : switch (nodeTag(expr))
4794 : {
4795 37502 : case T_Var:
4796 : {
4797 37502 : if (root)
4798 25620 : return var_is_nonnullable(root, (Var *) expr, source);
4799 : }
4800 11882 : break;
4801 423 : case T_Const:
4802 423 : return !((Const *) expr)->constisnull;
4803 165 : case T_CoalesceExpr:
4804 : {
4805 : /*
4806 : * A CoalesceExpr returns NULL if and only if all its
4807 : * arguments are NULL. Therefore, we can determine that a
4808 : * CoalesceExpr cannot be NULL if at least one of its
4809 : * arguments can be proven non-nullable.
4810 : */
4811 165 : CoalesceExpr *coalesceexpr = (CoalesceExpr *) expr;
4812 :
4813 570 : foreach_ptr(Expr, arg, coalesceexpr->args)
4814 : {
4815 330 : if (expr_is_nonnullable(root, arg, source))
4816 45 : return true;
4817 : }
4818 : }
4819 120 : break;
4820 15 : case T_MinMaxExpr:
4821 : {
4822 : /*
4823 : * Like CoalesceExpr, a MinMaxExpr returns NULL only if all
4824 : * its arguments evaluate to NULL.
4825 : */
4826 15 : MinMaxExpr *minmaxexpr = (MinMaxExpr *) expr;
4827 :
4828 50 : foreach_ptr(Expr, arg, minmaxexpr->args)
4829 : {
4830 30 : if (expr_is_nonnullable(root, arg, source))
4831 5 : return true;
4832 : }
4833 : }
4834 10 : break;
4835 81 : case T_CaseExpr:
4836 : {
4837 : /*
4838 : * A CASE expression is non-nullable if all branch results are
4839 : * non-nullable. We must also verify that the default result
4840 : * (ELSE) exists and is non-nullable.
4841 : */
4842 81 : CaseExpr *caseexpr = (CaseExpr *) expr;
4843 :
4844 : /* The default result must be present and non-nullable */
4845 81 : if (caseexpr->defresult == NULL ||
4846 81 : !expr_is_nonnullable(root, caseexpr->defresult, source))
4847 66 : return false;
4848 :
4849 : /* All branch results must be non-nullable */
4850 25 : foreach_ptr(CaseWhen, casewhen, caseexpr->args)
4851 : {
4852 15 : if (!expr_is_nonnullable(root, casewhen->result, source))
4853 10 : return false;
4854 : }
4855 :
4856 5 : return true;
4857 : }
4858 : break;
4859 5 : case T_ArrayExpr:
4860 : {
4861 : /*
4862 : * An ARRAY[] expression always returns a valid Array object,
4863 : * even if it is empty (ARRAY[]) or contains NULLs
4864 : * (ARRAY[NULL]). It never evaluates to a SQL NULL.
4865 : */
4866 5 : return true;
4867 : }
4868 7 : case T_NullTest:
4869 : {
4870 : /*
4871 : * An IS NULL / IS NOT NULL expression always returns a
4872 : * boolean value. It never returns SQL NULL.
4873 : */
4874 7 : return true;
4875 : }
4876 5 : case T_BooleanTest:
4877 : {
4878 : /*
4879 : * A BooleanTest expression always evaluates to a boolean
4880 : * value. It never returns SQL NULL.
4881 : */
4882 5 : return true;
4883 : }
4884 5 : case T_DistinctExpr:
4885 : {
4886 : /*
4887 : * IS DISTINCT FROM never returns NULL, effectively acting as
4888 : * though NULL were a normal data value.
4889 : */
4890 5 : return true;
4891 : }
4892 63 : case T_RelabelType:
4893 : {
4894 : /*
4895 : * RelabelType does not change the nullability of the data.
4896 : * The result is non-nullable if and only if the argument is
4897 : * non-nullable.
4898 : */
4899 63 : return expr_is_nonnullable(root, ((RelabelType *) expr)->arg,
4900 : source);
4901 : }
4902 4216 : default:
4903 4216 : break;
4904 : }
4905 :
4906 16228 : return false;
4907 : }
4908 :
4909 : /*
4910 : * expand_function_arguments: convert named-notation args to positional args
4911 : * and/or insert default args, as needed
4912 : *
4913 : * Returns a possibly-transformed version of the args list.
4914 : *
4915 : * If include_out_arguments is true, then the args list and the result
4916 : * include OUT arguments.
4917 : *
4918 : * The expected result type of the call must be given, for sanity-checking
4919 : * purposes. Also, we ask the caller to provide the function's actual
4920 : * pg_proc tuple, not just its OID.
4921 : *
4922 : * If we need to change anything, the input argument list is copied, not
4923 : * modified.
4924 : *
4925 : * Note: this gets applied to operator argument lists too, even though the
4926 : * cases it handles should never occur there. This should be OK since it
4927 : * will fall through very quickly if there's nothing to do.
4928 : */
4929 : List *
4930 969067 : expand_function_arguments(List *args, bool include_out_arguments,
4931 : Oid result_type, HeapTuple func_tuple)
4932 : {
4933 969067 : Form_pg_proc funcform = (Form_pg_proc) GETSTRUCT(func_tuple);
4934 969067 : Oid *proargtypes = funcform->proargtypes.values;
4935 969067 : int pronargs = funcform->pronargs;
4936 969067 : bool has_named_args = false;
4937 : ListCell *lc;
4938 :
4939 : /*
4940 : * If we are asked to match to OUT arguments, then use the proallargtypes
4941 : * array (which includes those); otherwise use proargtypes (which
4942 : * doesn't). Of course, if proallargtypes is null, we always use
4943 : * proargtypes. (Fetching proallargtypes is annoyingly expensive
4944 : * considering that we may have nothing to do here, but fortunately the
4945 : * common case is include_out_arguments == false.)
4946 : */
4947 969067 : if (include_out_arguments)
4948 : {
4949 : Datum proallargtypes;
4950 : bool isNull;
4951 :
4952 291 : proallargtypes = SysCacheGetAttr(PROCOID, func_tuple,
4953 : Anum_pg_proc_proallargtypes,
4954 : &isNull);
4955 291 : if (!isNull)
4956 : {
4957 119 : ArrayType *arr = DatumGetArrayTypeP(proallargtypes);
4958 :
4959 119 : pronargs = ARR_DIMS(arr)[0];
4960 119 : if (ARR_NDIM(arr) != 1 ||
4961 119 : pronargs < 0 ||
4962 119 : ARR_HASNULL(arr) ||
4963 119 : ARR_ELEMTYPE(arr) != OIDOID)
4964 0 : elog(ERROR, "proallargtypes is not a 1-D Oid array or it contains nulls");
4965 : Assert(pronargs >= funcform->pronargs);
4966 119 : proargtypes = (Oid *) ARR_DATA_PTR(arr);
4967 : }
4968 : }
4969 :
4970 : /* Do we have any named arguments? */
4971 2675832 : foreach(lc, args)
4972 : {
4973 1716185 : Node *arg = (Node *) lfirst(lc);
4974 :
4975 1716185 : if (IsA(arg, NamedArgExpr))
4976 : {
4977 9420 : has_named_args = true;
4978 9420 : break;
4979 : }
4980 : }
4981 :
4982 : /* If so, we must apply reorder_function_arguments */
4983 969067 : if (has_named_args)
4984 : {
4985 9420 : args = reorder_function_arguments(args, pronargs, func_tuple);
4986 : /* Recheck argument types and add casts if needed */
4987 9420 : recheck_cast_function_args(args, result_type,
4988 : proargtypes, pronargs,
4989 : func_tuple);
4990 : }
4991 959647 : else if (list_length(args) < pronargs)
4992 : {
4993 : /* No named args, but we seem to be short some defaults */
4994 5513 : args = add_function_defaults(args, pronargs, func_tuple);
4995 : /* Recheck argument types and add casts if needed */
4996 5513 : recheck_cast_function_args(args, result_type,
4997 : proargtypes, pronargs,
4998 : func_tuple);
4999 : }
5000 :
5001 969067 : return args;
5002 : }
5003 :
5004 : /*
5005 : * reorder_function_arguments: convert named-notation args to positional args
5006 : *
5007 : * This function also inserts default argument values as needed, since it's
5008 : * impossible to form a truly valid positional call without that.
5009 : */
5010 : static List *
5011 9420 : reorder_function_arguments(List *args, int pronargs, HeapTuple func_tuple)
5012 : {
5013 9420 : Form_pg_proc funcform = (Form_pg_proc) GETSTRUCT(func_tuple);
5014 9420 : int nargsprovided = list_length(args);
5015 : Node *argarray[FUNC_MAX_ARGS];
5016 : ListCell *lc;
5017 : int i;
5018 :
5019 : Assert(nargsprovided <= pronargs);
5020 9420 : if (pronargs < 0 || pronargs > FUNC_MAX_ARGS)
5021 0 : elog(ERROR, "too many function arguments");
5022 9420 : memset(argarray, 0, pronargs * sizeof(Node *));
5023 :
5024 : /* Deconstruct the argument list into an array indexed by argnumber */
5025 9420 : i = 0;
5026 38160 : foreach(lc, args)
5027 : {
5028 28740 : Node *arg = (Node *) lfirst(lc);
5029 :
5030 28740 : if (!IsA(arg, NamedArgExpr))
5031 : {
5032 : /* positional argument, assumed to precede all named args */
5033 : Assert(argarray[i] == NULL);
5034 1862 : argarray[i++] = arg;
5035 : }
5036 : else
5037 : {
5038 26878 : NamedArgExpr *na = (NamedArgExpr *) arg;
5039 :
5040 : Assert(na->argnumber >= 0 && na->argnumber < pronargs);
5041 : Assert(argarray[na->argnumber] == NULL);
5042 26878 : argarray[na->argnumber] = (Node *) na->arg;
5043 : }
5044 : }
5045 :
5046 : /*
5047 : * Fetch default expressions, if needed, and insert into array at proper
5048 : * locations (they aren't necessarily consecutive or all used)
5049 : */
5050 9420 : if (nargsprovided < pronargs)
5051 : {
5052 4477 : List *defaults = fetch_function_defaults(func_tuple);
5053 :
5054 4477 : i = pronargs - funcform->pronargdefaults;
5055 24918 : foreach(lc, defaults)
5056 : {
5057 20441 : if (argarray[i] == NULL)
5058 8889 : argarray[i] = (Node *) lfirst(lc);
5059 20441 : i++;
5060 : }
5061 : }
5062 :
5063 : /* Now reconstruct the args list in proper order */
5064 9420 : args = NIL;
5065 47049 : for (i = 0; i < pronargs; i++)
5066 : {
5067 : Assert(argarray[i] != NULL);
5068 37629 : args = lappend(args, argarray[i]);
5069 : }
5070 :
5071 9420 : return args;
5072 : }
5073 :
5074 : /*
5075 : * add_function_defaults: add missing function arguments from its defaults
5076 : *
5077 : * This is used only when the argument list was positional to begin with,
5078 : * and so we know we just need to add defaults at the end.
5079 : */
5080 : static List *
5081 5513 : add_function_defaults(List *args, int pronargs, HeapTuple func_tuple)
5082 : {
5083 5513 : int nargsprovided = list_length(args);
5084 : List *defaults;
5085 : int ndelete;
5086 :
5087 : /* Get all the default expressions from the pg_proc tuple */
5088 5513 : defaults = fetch_function_defaults(func_tuple);
5089 :
5090 : /* Delete any unused defaults from the list */
5091 5513 : ndelete = nargsprovided + list_length(defaults) - pronargs;
5092 5513 : if (ndelete < 0)
5093 0 : elog(ERROR, "not enough default arguments");
5094 5513 : if (ndelete > 0)
5095 180 : defaults = list_delete_first_n(defaults, ndelete);
5096 :
5097 : /* And form the combined argument list, not modifying the input list */
5098 5513 : return list_concat_copy(args, defaults);
5099 : }
5100 :
5101 : /*
5102 : * fetch_function_defaults: get function's default arguments as expression list
5103 : */
5104 : static List *
5105 9990 : fetch_function_defaults(HeapTuple func_tuple)
5106 : {
5107 : List *defaults;
5108 : Datum proargdefaults;
5109 : char *str;
5110 :
5111 9990 : proargdefaults = SysCacheGetAttrNotNull(PROCOID, func_tuple,
5112 : Anum_pg_proc_proargdefaults);
5113 9990 : str = TextDatumGetCString(proargdefaults);
5114 9990 : defaults = castNode(List, stringToNode(str));
5115 9990 : pfree(str);
5116 9990 : return defaults;
5117 : }
5118 :
5119 : /*
5120 : * recheck_cast_function_args: recheck function args and typecast as needed
5121 : * after adding defaults.
5122 : *
5123 : * It is possible for some of the defaulted arguments to be polymorphic;
5124 : * therefore we can't assume that the default expressions have the correct
5125 : * data types already. We have to re-resolve polymorphics and do coercion
5126 : * just like the parser did.
5127 : *
5128 : * This should be a no-op if there are no polymorphic arguments,
5129 : * but we do it anyway to be sure.
5130 : *
5131 : * Note: if any casts are needed, the args list is modified in-place;
5132 : * caller should have already copied the list structure.
5133 : */
5134 : static void
5135 14933 : recheck_cast_function_args(List *args, Oid result_type,
5136 : Oid *proargtypes, int pronargs,
5137 : HeapTuple func_tuple)
5138 : {
5139 14933 : Form_pg_proc funcform = (Form_pg_proc) GETSTRUCT(func_tuple);
5140 : int nargs;
5141 : Oid actual_arg_types[FUNC_MAX_ARGS];
5142 : Oid declared_arg_types[FUNC_MAX_ARGS];
5143 : Oid rettype;
5144 : ListCell *lc;
5145 :
5146 14933 : if (list_length(args) > FUNC_MAX_ARGS)
5147 0 : elog(ERROR, "too many function arguments");
5148 14933 : nargs = 0;
5149 72971 : foreach(lc, args)
5150 : {
5151 58038 : actual_arg_types[nargs++] = exprType((Node *) lfirst(lc));
5152 : }
5153 : Assert(nargs == pronargs);
5154 14933 : memcpy(declared_arg_types, proargtypes, pronargs * sizeof(Oid));
5155 14933 : rettype = enforce_generic_type_consistency(actual_arg_types,
5156 : declared_arg_types,
5157 : nargs,
5158 : funcform->prorettype,
5159 : false);
5160 : /* let's just check we got the same answer as the parser did ... */
5161 14933 : if (rettype != result_type)
5162 0 : elog(ERROR, "function's resolved result type changed during planning");
5163 :
5164 : /* perform any necessary typecasting of arguments */
5165 14933 : make_fn_arguments(NULL, args, actual_arg_types, declared_arg_types);
5166 14933 : }
5167 :
5168 : /*
5169 : * evaluate_function: try to pre-evaluate a function call
5170 : *
5171 : * We can do this if the function is strict and has any constant-null inputs
5172 : * (just return a null constant), or if the function is immutable and has all
5173 : * constant inputs (call it and return the result as a Const node). In
5174 : * estimation mode we are willing to pre-evaluate stable functions too.
5175 : *
5176 : * Returns a simplified expression if successful, or NULL if cannot
5177 : * simplify the function.
5178 : */
5179 : static Expr *
5180 967554 : evaluate_function(Oid funcid, Oid result_type, int32 result_typmod,
5181 : Oid result_collid, Oid input_collid, List *args,
5182 : bool funcvariadic,
5183 : HeapTuple func_tuple,
5184 : eval_const_expressions_context *context)
5185 : {
5186 967554 : Form_pg_proc funcform = (Form_pg_proc) GETSTRUCT(func_tuple);
5187 967554 : bool has_nonconst_input = false;
5188 967554 : bool has_null_input = false;
5189 : ListCell *arg;
5190 : FuncExpr *newexpr;
5191 :
5192 : /*
5193 : * Can't simplify if it returns a set.
5194 : */
5195 967554 : if (funcform->proretset)
5196 46009 : return NULL;
5197 :
5198 : /*
5199 : * Can't simplify if it returns RECORD. The immediate problem is that it
5200 : * will be needing an expected tupdesc which we can't supply here.
5201 : *
5202 : * In the case where it has OUT parameters, we could build an expected
5203 : * tupdesc from those, but there may be other gotchas lurking. In
5204 : * particular, if the function were to return NULL, we would produce a
5205 : * null constant with no remaining indication of which concrete record
5206 : * type it is. For now, seems best to leave the function call unreduced.
5207 : */
5208 921545 : if (funcform->prorettype == RECORDOID)
5209 3919 : return NULL;
5210 :
5211 : /*
5212 : * Check for constant inputs and especially constant-NULL inputs.
5213 : */
5214 2557622 : foreach(arg, args)
5215 : {
5216 1639996 : if (IsA(lfirst(arg), Const))
5217 727913 : has_null_input |= ((Const *) lfirst(arg))->constisnull;
5218 : else
5219 912083 : has_nonconst_input = true;
5220 : }
5221 :
5222 : /*
5223 : * If the function is strict and has a constant-NULL input, it will never
5224 : * be called at all, so we can replace the call by a NULL constant, even
5225 : * if there are other inputs that aren't constant, and even if the
5226 : * function is not otherwise immutable.
5227 : */
5228 917626 : if (funcform->proisstrict && has_null_input)
5229 4438 : return (Expr *) makeNullConst(result_type, result_typmod,
5230 : result_collid);
5231 :
5232 : /*
5233 : * Otherwise, can simplify only if all inputs are constants. (For a
5234 : * non-strict function, constant NULL inputs are treated the same as
5235 : * constant non-NULL inputs.)
5236 : */
5237 913188 : if (has_nonconst_input)
5238 694895 : return NULL;
5239 :
5240 : /*
5241 : * Ordinarily we are only allowed to simplify immutable functions. But for
5242 : * purposes of estimation, we consider it okay to simplify functions that
5243 : * are merely stable; the risk that the result might change from planning
5244 : * time to execution time is worth taking in preference to not being able
5245 : * to estimate the value at all.
5246 : */
5247 218293 : if (funcform->provolatile == PROVOLATILE_IMMUTABLE)
5248 : /* okay */ ;
5249 89286 : else if (context->estimate && funcform->provolatile == PROVOLATILE_STABLE)
5250 : /* okay */ ;
5251 : else
5252 87404 : return NULL;
5253 :
5254 : /*
5255 : * OK, looks like we can simplify this operator/function.
5256 : *
5257 : * Build a new FuncExpr node containing the already-simplified arguments.
5258 : */
5259 130889 : newexpr = makeNode(FuncExpr);
5260 130889 : newexpr->funcid = funcid;
5261 130889 : newexpr->funcresulttype = result_type;
5262 130889 : newexpr->funcretset = false;
5263 130889 : newexpr->funcvariadic = funcvariadic;
5264 130889 : newexpr->funcformat = COERCE_EXPLICIT_CALL; /* doesn't matter */
5265 130889 : newexpr->funccollid = result_collid; /* doesn't matter */
5266 130889 : newexpr->inputcollid = input_collid;
5267 130889 : newexpr->args = args;
5268 130889 : newexpr->location = -1;
5269 :
5270 130889 : return evaluate_expr((Expr *) newexpr, result_type, result_typmod,
5271 : result_collid);
5272 : }
5273 :
5274 : /*
5275 : * inline_function: try to expand a function call inline
5276 : *
5277 : * If the function is a sufficiently simple SQL-language function
5278 : * (just "SELECT expression"), then we can inline it and avoid the rather
5279 : * high per-call overhead of SQL functions. Furthermore, this can expose
5280 : * opportunities for constant-folding within the function expression.
5281 : *
5282 : * We have to beware of some special cases however. A directly or
5283 : * indirectly recursive function would cause us to recurse forever,
5284 : * so we keep track of which functions we are already expanding and
5285 : * do not re-expand them. Also, if a parameter is used more than once
5286 : * in the SQL-function body, we require it not to contain any volatile
5287 : * functions (volatiles might deliver inconsistent answers) nor to be
5288 : * unreasonably expensive to evaluate. The expensiveness check not only
5289 : * prevents us from doing multiple evaluations of an expensive parameter
5290 : * at runtime, but is a safety value to limit growth of an expression due
5291 : * to repeated inlining.
5292 : *
5293 : * We must also beware of changing the volatility or strictness status of
5294 : * functions by inlining them.
5295 : *
5296 : * Also, at the moment we can't inline functions returning RECORD. This
5297 : * doesn't work in the general case because it discards information such
5298 : * as OUT-parameter declarations.
5299 : *
5300 : * Also, context-dependent expression nodes in the argument list are trouble.
5301 : *
5302 : * Returns a simplified expression if successful, or NULL if cannot
5303 : * simplify the function.
5304 : */
5305 : static Expr *
5306 832128 : inline_function(Oid funcid, Oid result_type, Oid result_collid,
5307 : Oid input_collid, List *args,
5308 : bool funcvariadic,
5309 : HeapTuple func_tuple,
5310 : eval_const_expressions_context *context)
5311 : {
5312 832128 : Form_pg_proc funcform = (Form_pg_proc) GETSTRUCT(func_tuple);
5313 : char *src;
5314 : Datum tmp;
5315 : bool isNull;
5316 : MemoryContext oldcxt;
5317 : MemoryContext mycxt;
5318 : inline_error_callback_arg callback_arg;
5319 : ErrorContextCallback sqlerrcontext;
5320 : FuncExpr *fexpr;
5321 : SQLFunctionParseInfoPtr pinfo;
5322 : TupleDesc rettupdesc;
5323 : ParseState *pstate;
5324 : List *raw_parsetree_list;
5325 : List *querytree_list;
5326 : Query *querytree;
5327 : Node *newexpr;
5328 : int *usecounts;
5329 : ListCell *arg;
5330 : int i;
5331 :
5332 : /*
5333 : * Forget it if the function is not SQL-language or has other showstopper
5334 : * properties. (The prokind and nargs checks are just paranoia.)
5335 : */
5336 832128 : if (funcform->prolang != SQLlanguageId ||
5337 7499 : funcform->prokind != PROKIND_FUNCTION ||
5338 7499 : funcform->prosecdef ||
5339 7489 : funcform->proretset ||
5340 6056 : funcform->prorettype == RECORDOID ||
5341 11567 : !heap_attisnull(func_tuple, Anum_pg_proc_proconfig, NULL) ||
5342 5766 : funcform->pronargs != list_length(args))
5343 826362 : return NULL;
5344 :
5345 : /* Check for recursive function, and give up trying to expand if so */
5346 5766 : if (list_member_oid(context->active_fns, funcid))
5347 10 : return NULL;
5348 :
5349 : /* Check permission to call function (fail later, if not) */
5350 5756 : if (object_aclcheck(ProcedureRelationId, funcid, GetUserId(), ACL_EXECUTE) != ACLCHECK_OK)
5351 13 : return NULL;
5352 :
5353 : /* Check whether a plugin wants to hook function entry/exit */
5354 5743 : if (FmgrHookIsNeeded(funcid))
5355 0 : return NULL;
5356 :
5357 : /*
5358 : * Make a temporary memory context, so that we don't leak all the stuff
5359 : * that parsing might create.
5360 : */
5361 5743 : mycxt = AllocSetContextCreate(CurrentMemoryContext,
5362 : "inline_function",
5363 : ALLOCSET_DEFAULT_SIZES);
5364 5743 : oldcxt = MemoryContextSwitchTo(mycxt);
5365 :
5366 : /*
5367 : * We need a dummy FuncExpr node containing the already-simplified
5368 : * arguments. (In some cases we don't really need it, but building it is
5369 : * cheap enough that it's not worth contortions to avoid.)
5370 : */
5371 5743 : fexpr = makeNode(FuncExpr);
5372 5743 : fexpr->funcid = funcid;
5373 5743 : fexpr->funcresulttype = result_type;
5374 5743 : fexpr->funcretset = false;
5375 5743 : fexpr->funcvariadic = funcvariadic;
5376 5743 : fexpr->funcformat = COERCE_EXPLICIT_CALL; /* doesn't matter */
5377 5743 : fexpr->funccollid = result_collid; /* doesn't matter */
5378 5743 : fexpr->inputcollid = input_collid;
5379 5743 : fexpr->args = args;
5380 5743 : fexpr->location = -1;
5381 :
5382 : /* Fetch the function body */
5383 5743 : tmp = SysCacheGetAttrNotNull(PROCOID, func_tuple, Anum_pg_proc_prosrc);
5384 5743 : src = TextDatumGetCString(tmp);
5385 :
5386 : /*
5387 : * Setup error traceback support for ereport(). This is so that we can
5388 : * finger the function that bad information came from.
5389 : */
5390 5743 : callback_arg.proname = NameStr(funcform->proname);
5391 5743 : callback_arg.prosrc = src;
5392 :
5393 5743 : sqlerrcontext.callback = sql_inline_error_callback;
5394 5743 : sqlerrcontext.arg = &callback_arg;
5395 5743 : sqlerrcontext.previous = error_context_stack;
5396 5743 : error_context_stack = &sqlerrcontext;
5397 :
5398 : /* If we have prosqlbody, pay attention to that not prosrc */
5399 5743 : tmp = SysCacheGetAttr(PROCOID,
5400 : func_tuple,
5401 : Anum_pg_proc_prosqlbody,
5402 : &isNull);
5403 5743 : if (!isNull)
5404 : {
5405 : Node *n;
5406 : List *query_list;
5407 :
5408 3299 : n = stringToNode(TextDatumGetCString(tmp));
5409 3299 : if (IsA(n, List))
5410 2652 : query_list = linitial_node(List, castNode(List, n));
5411 : else
5412 647 : query_list = list_make1(n);
5413 3299 : if (list_length(query_list) != 1)
5414 5 : goto fail;
5415 3294 : querytree = linitial(query_list);
5416 :
5417 : /*
5418 : * Because we'll insist below that the querytree have an empty rtable
5419 : * and no sublinks, it cannot have any relation references that need
5420 : * to be locked or rewritten. So we can omit those steps.
5421 : */
5422 : }
5423 : else
5424 : {
5425 : /* Set up to handle parameters while parsing the function body. */
5426 2444 : pinfo = prepare_sql_fn_parse_info(func_tuple,
5427 : (Node *) fexpr,
5428 : input_collid);
5429 :
5430 : /*
5431 : * We just do parsing and parse analysis, not rewriting, because
5432 : * rewriting will not affect table-free-SELECT-only queries, which is
5433 : * all that we care about. Also, we can punt as soon as we detect
5434 : * more than one command in the function body.
5435 : */
5436 2444 : raw_parsetree_list = pg_parse_query(src);
5437 2444 : if (list_length(raw_parsetree_list) != 1)
5438 45 : goto fail;
5439 :
5440 2399 : pstate = make_parsestate(NULL);
5441 2399 : pstate->p_sourcetext = src;
5442 2399 : sql_fn_parser_setup(pstate, pinfo);
5443 :
5444 2399 : querytree = transformTopLevelStmt(pstate, linitial(raw_parsetree_list));
5445 :
5446 2395 : free_parsestate(pstate);
5447 : }
5448 :
5449 : /*
5450 : * The single command must be a simple "SELECT expression".
5451 : *
5452 : * Note: if you change the tests involved in this, see also plpgsql's
5453 : * exec_simple_check_plan(). That generally needs to have the same idea
5454 : * of what's a "simple expression", so that inlining a function that
5455 : * previously wasn't inlined won't change plpgsql's conclusion.
5456 : */
5457 5689 : if (!IsA(querytree, Query) ||
5458 5689 : querytree->commandType != CMD_SELECT ||
5459 5588 : querytree->hasAggs ||
5460 5428 : querytree->hasWindowFuncs ||
5461 5428 : querytree->hasTargetSRFs ||
5462 5428 : querytree->hasSubLinks ||
5463 4287 : querytree->cteList ||
5464 4287 : querytree->rtable ||
5465 2725 : querytree->jointree->fromlist ||
5466 2725 : querytree->jointree->quals ||
5467 2725 : querytree->groupClause ||
5468 2725 : querytree->groupingSets ||
5469 2725 : querytree->havingQual ||
5470 2725 : querytree->windowClause ||
5471 2725 : querytree->distinctClause ||
5472 2725 : querytree->sortClause ||
5473 2725 : querytree->limitOffset ||
5474 2725 : querytree->limitCount ||
5475 5342 : querytree->setOperations ||
5476 2671 : list_length(querytree->targetList) != 1)
5477 3068 : goto fail;
5478 :
5479 : /* If the function result is composite, resolve it */
5480 2621 : (void) get_expr_result_type((Node *) fexpr,
5481 : NULL,
5482 : &rettupdesc);
5483 :
5484 : /*
5485 : * Make sure the function (still) returns what it's declared to. This
5486 : * will raise an error if wrong, but that's okay since the function would
5487 : * fail at runtime anyway. Note that check_sql_fn_retval will also insert
5488 : * a coercion if needed to make the tlist expression match the declared
5489 : * type of the function.
5490 : *
5491 : * Note: we do not try this until we have verified that no rewriting was
5492 : * needed; that's probably not important, but let's be careful.
5493 : */
5494 2621 : querytree_list = list_make1(querytree);
5495 2621 : if (check_sql_fn_retval(list_make1(querytree_list),
5496 : result_type, rettupdesc,
5497 2621 : funcform->prokind,
5498 : false))
5499 10 : goto fail; /* reject whole-tuple-result cases */
5500 :
5501 : /*
5502 : * Given the tests above, check_sql_fn_retval shouldn't have decided to
5503 : * inject a projection step, but let's just make sure.
5504 : */
5505 2607 : if (querytree != linitial(querytree_list))
5506 0 : goto fail;
5507 :
5508 : /* Now we can grab the tlist expression */
5509 2607 : newexpr = (Node *) ((TargetEntry *) linitial(querytree->targetList))->expr;
5510 :
5511 : /*
5512 : * If the SQL function returns VOID, we can only inline it if it is a
5513 : * SELECT of an expression returning VOID (ie, it's just a redirection to
5514 : * another VOID-returning function). In all non-VOID-returning cases,
5515 : * check_sql_fn_retval should ensure that newexpr returns the function's
5516 : * declared result type, so this test shouldn't fail otherwise; but we may
5517 : * as well cope gracefully if it does.
5518 : */
5519 2607 : if (exprType(newexpr) != result_type)
5520 15 : goto fail;
5521 :
5522 : /*
5523 : * Additional validity checks on the expression. It mustn't be more
5524 : * volatile than the surrounding function (this is to avoid breaking hacks
5525 : * that involve pretending a function is immutable when it really ain't).
5526 : * If the surrounding function is declared strict, then the expression
5527 : * must contain only strict constructs and must use all of the function
5528 : * parameters (this is overkill, but an exact analysis is hard).
5529 : */
5530 3150 : if (funcform->provolatile == PROVOLATILE_IMMUTABLE &&
5531 558 : contain_mutable_functions(newexpr))
5532 9 : goto fail;
5533 3357 : else if (funcform->provolatile == PROVOLATILE_STABLE &&
5534 774 : contain_volatile_functions(newexpr))
5535 0 : goto fail;
5536 :
5537 3912 : if (funcform->proisstrict &&
5538 1329 : contain_nonstrict_functions(newexpr))
5539 37 : goto fail;
5540 :
5541 : /*
5542 : * If any parameter expression contains a context-dependent node, we can't
5543 : * inline, for fear of putting such a node into the wrong context.
5544 : */
5545 2546 : if (contain_context_dependent_node((Node *) args))
5546 5 : goto fail;
5547 :
5548 : /*
5549 : * We may be able to do it; there are still checks on parameter usage to
5550 : * make, but those are most easily done in combination with the actual
5551 : * substitution of the inputs. So start building expression with inputs
5552 : * substituted.
5553 : */
5554 2541 : usecounts = (int *) palloc0(funcform->pronargs * sizeof(int));
5555 2541 : newexpr = substitute_actual_parameters(newexpr, funcform->pronargs,
5556 : args, usecounts);
5557 :
5558 : /* Now check for parameter usage */
5559 2541 : i = 0;
5560 6778 : foreach(arg, args)
5561 : {
5562 4237 : Node *param = lfirst(arg);
5563 :
5564 4237 : if (usecounts[i] == 0)
5565 : {
5566 : /* Param not used at all: uncool if func is strict */
5567 211 : if (funcform->proisstrict)
5568 0 : goto fail;
5569 : }
5570 4026 : else if (usecounts[i] != 1)
5571 : {
5572 : /* Param used multiple times: uncool if expensive or volatile */
5573 : QualCost eval_cost;
5574 :
5575 : /*
5576 : * We define "expensive" as "contains any subplan or more than 10
5577 : * operators". Note that the subplan search has to be done
5578 : * explicitly, since cost_qual_eval() will barf on unplanned
5579 : * subselects.
5580 : */
5581 281 : if (contain_subplans(param))
5582 0 : goto fail;
5583 281 : cost_qual_eval(&eval_cost, list_make1(param), NULL);
5584 281 : if (eval_cost.startup + eval_cost.per_tuple >
5585 281 : 10 * cpu_operator_cost)
5586 0 : goto fail;
5587 :
5588 : /*
5589 : * Check volatility last since this is more expensive than the
5590 : * above tests
5591 : */
5592 281 : if (contain_volatile_functions(param))
5593 0 : goto fail;
5594 : }
5595 4237 : i++;
5596 : }
5597 :
5598 : /*
5599 : * Whew --- we can make the substitution. Copy the modified expression
5600 : * out of the temporary memory context, and clean up.
5601 : */
5602 2541 : MemoryContextSwitchTo(oldcxt);
5603 :
5604 2541 : newexpr = copyObject(newexpr);
5605 :
5606 2541 : MemoryContextDelete(mycxt);
5607 :
5608 : /*
5609 : * If the result is of a collatable type, force the result to expose the
5610 : * correct collation. In most cases this does not matter, but it's
5611 : * possible that the function result is used directly as a sort key or in
5612 : * other places where we expect exprCollation() to tell the truth.
5613 : */
5614 2541 : if (OidIsValid(result_collid))
5615 : {
5616 1171 : Oid exprcoll = exprCollation(newexpr);
5617 :
5618 1171 : if (OidIsValid(exprcoll) && exprcoll != result_collid)
5619 : {
5620 18 : CollateExpr *newnode = makeNode(CollateExpr);
5621 :
5622 18 : newnode->arg = (Expr *) newexpr;
5623 18 : newnode->collOid = result_collid;
5624 18 : newnode->location = -1;
5625 :
5626 18 : newexpr = (Node *) newnode;
5627 : }
5628 : }
5629 :
5630 : /*
5631 : * Since there is now no trace of the function in the plan tree, we must
5632 : * explicitly record the plan's dependency on the function.
5633 : */
5634 2541 : if (context->root)
5635 2388 : record_plan_function_dependency(context->root, funcid);
5636 :
5637 : /*
5638 : * Recursively try to simplify the modified expression. Here we must add
5639 : * the current function to the context list of active functions.
5640 : */
5641 2541 : context->active_fns = lappend_oid(context->active_fns, funcid);
5642 2541 : newexpr = eval_const_expressions_mutator(newexpr, context);
5643 2540 : context->active_fns = list_delete_last(context->active_fns);
5644 :
5645 2540 : error_context_stack = sqlerrcontext.previous;
5646 :
5647 2540 : return (Expr *) newexpr;
5648 :
5649 : /* Here if func is not inlinable: release temp memory and return NULL */
5650 3194 : fail:
5651 3194 : MemoryContextSwitchTo(oldcxt);
5652 3194 : MemoryContextDelete(mycxt);
5653 3194 : error_context_stack = sqlerrcontext.previous;
5654 :
5655 3194 : return NULL;
5656 : }
5657 :
5658 : /*
5659 : * Replace Param nodes by appropriate actual parameters
5660 : */
5661 : static Node *
5662 2541 : substitute_actual_parameters(Node *expr, int nargs, List *args,
5663 : int *usecounts)
5664 : {
5665 : substitute_actual_parameters_context context;
5666 :
5667 2541 : context.nargs = nargs;
5668 2541 : context.args = args;
5669 2541 : context.usecounts = usecounts;
5670 :
5671 2541 : return substitute_actual_parameters_mutator(expr, &context);
5672 : }
5673 :
5674 : static Node *
5675 14469 : substitute_actual_parameters_mutator(Node *node,
5676 : substitute_actual_parameters_context *context)
5677 : {
5678 14469 : if (node == NULL)
5679 413 : return NULL;
5680 14056 : if (IsA(node, Param))
5681 : {
5682 4325 : Param *param = (Param *) node;
5683 :
5684 4325 : if (param->paramkind != PARAM_EXTERN)
5685 0 : elog(ERROR, "unexpected paramkind: %d", (int) param->paramkind);
5686 4325 : if (param->paramid <= 0 || param->paramid > context->nargs)
5687 0 : elog(ERROR, "invalid paramid: %d", param->paramid);
5688 :
5689 : /* Count usage of parameter */
5690 4325 : context->usecounts[param->paramid - 1]++;
5691 :
5692 : /* Select the appropriate actual arg and replace the Param with it */
5693 : /* We don't need to copy at this time (it'll get done later) */
5694 4325 : return list_nth(context->args, param->paramid - 1);
5695 : }
5696 9731 : return expression_tree_mutator(node, substitute_actual_parameters_mutator, context);
5697 : }
5698 :
5699 : /*
5700 : * error context callback to let us supply a call-stack traceback
5701 : */
5702 : static void
5703 13 : sql_inline_error_callback(void *arg)
5704 : {
5705 13 : inline_error_callback_arg *callback_arg = (inline_error_callback_arg *) arg;
5706 : int syntaxerrposition;
5707 :
5708 : /* If it's a syntax error, convert to internal syntax error report */
5709 13 : syntaxerrposition = geterrposition();
5710 13 : if (syntaxerrposition > 0)
5711 : {
5712 4 : errposition(0);
5713 4 : internalerrposition(syntaxerrposition);
5714 4 : internalerrquery(callback_arg->prosrc);
5715 : }
5716 :
5717 13 : errcontext("SQL function \"%s\" during inlining", callback_arg->proname);
5718 13 : }
5719 :
5720 : /*
5721 : * evaluate_expr: pre-evaluate a constant expression
5722 : *
5723 : * We use the executor's routine ExecEvalExpr() to avoid duplication of
5724 : * code and ensure we get the same result as the executor would get.
5725 : */
5726 : Expr *
5727 157695 : evaluate_expr(Expr *expr, Oid result_type, int32 result_typmod,
5728 : Oid result_collation)
5729 : {
5730 : EState *estate;
5731 : ExprState *exprstate;
5732 : MemoryContext oldcontext;
5733 : Datum const_val;
5734 : bool const_is_null;
5735 : int16 resultTypLen;
5736 : bool resultTypByVal;
5737 :
5738 : /*
5739 : * To use the executor, we need an EState.
5740 : */
5741 157695 : estate = CreateExecutorState();
5742 :
5743 : /* We can use the estate's working context to avoid memory leaks. */
5744 157695 : oldcontext = MemoryContextSwitchTo(estate->es_query_cxt);
5745 :
5746 : /* Make sure any opfuncids are filled in. */
5747 157695 : fix_opfuncids((Node *) expr);
5748 :
5749 : /*
5750 : * Prepare expr for execution. (Note: we can't use ExecPrepareExpr
5751 : * because it'd result in recursively invoking eval_const_expressions.)
5752 : */
5753 157695 : exprstate = ExecInitExpr(expr, NULL);
5754 :
5755 : /*
5756 : * And evaluate it.
5757 : *
5758 : * It is OK to use a default econtext because none of the ExecEvalExpr()
5759 : * code used in this situation will use econtext. That might seem
5760 : * fortuitous, but it's not so unreasonable --- a constant expression does
5761 : * not depend on context, by definition, n'est ce pas?
5762 : */
5763 157679 : const_val = ExecEvalExprSwitchContext(exprstate,
5764 157679 : GetPerTupleExprContext(estate),
5765 : &const_is_null);
5766 :
5767 : /* Get info needed about result datatype */
5768 155026 : get_typlenbyval(result_type, &resultTypLen, &resultTypByVal);
5769 :
5770 : /* Get back to outer memory context */
5771 155026 : MemoryContextSwitchTo(oldcontext);
5772 :
5773 : /*
5774 : * Must copy result out of sub-context used by expression eval.
5775 : *
5776 : * Also, if it's varlena, forcibly detoast it. This protects us against
5777 : * storing TOAST pointers into plans that might outlive the referenced
5778 : * data. (makeConst would handle detoasting anyway, but it's worth a few
5779 : * extra lines here so that we can do the copy and detoast in one step.)
5780 : */
5781 155026 : if (!const_is_null)
5782 : {
5783 150051 : if (resultTypLen == -1)
5784 70726 : const_val = PointerGetDatum(PG_DETOAST_DATUM_COPY(const_val));
5785 : else
5786 79325 : const_val = datumCopy(const_val, resultTypByVal, resultTypLen);
5787 : }
5788 :
5789 : /* Release all the junk we just created */
5790 155026 : FreeExecutorState(estate);
5791 :
5792 : /*
5793 : * Make the constant result node.
5794 : */
5795 155026 : return (Expr *) makeConst(result_type, result_typmod, result_collation,
5796 : resultTypLen,
5797 : const_val, const_is_null,
5798 : resultTypByVal);
5799 : }
5800 :
5801 :
5802 : /*
5803 : * inline_function_in_from
5804 : * Attempt to "inline" a function in the FROM clause.
5805 : *
5806 : * "rte" is an RTE_FUNCTION rangetable entry. If it represents a call of a
5807 : * function that can be inlined, expand the function and return the
5808 : * substitute Query structure. Otherwise, return NULL.
5809 : *
5810 : * We assume that the RTE's expression has already been put through
5811 : * eval_const_expressions(), which among other things will take care of
5812 : * default arguments and named-argument notation.
5813 : *
5814 : * This has a good deal of similarity to inline_function(), but that's
5815 : * for the general-expression case, and there are enough differences to
5816 : * justify separate functions.
5817 : */
5818 : Query *
5819 36136 : inline_function_in_from(PlannerInfo *root, RangeTblEntry *rte)
5820 : {
5821 : RangeTblFunction *rtfunc;
5822 : FuncExpr *fexpr;
5823 : Oid func_oid;
5824 : HeapTuple func_tuple;
5825 : Form_pg_proc funcform;
5826 : MemoryContext oldcxt;
5827 : MemoryContext mycxt;
5828 : Datum tmp;
5829 : char *src;
5830 : inline_error_callback_arg callback_arg;
5831 : ErrorContextCallback sqlerrcontext;
5832 36136 : Query *querytree = NULL;
5833 :
5834 : Assert(rte->rtekind == RTE_FUNCTION);
5835 :
5836 : /*
5837 : * Guard against infinite recursion during expansion by checking for stack
5838 : * overflow. (There's no need to do more.)
5839 : */
5840 36136 : check_stack_depth();
5841 :
5842 : /* Fail if the RTE has ORDINALITY - we don't implement that here. */
5843 36136 : if (rte->funcordinality)
5844 775 : return NULL;
5845 :
5846 : /* Fail if RTE isn't a single, simple FuncExpr */
5847 35361 : if (list_length(rte->functions) != 1)
5848 57 : return NULL;
5849 35304 : rtfunc = (RangeTblFunction *) linitial(rte->functions);
5850 :
5851 35304 : if (!IsA(rtfunc->funcexpr, FuncExpr))
5852 345 : return NULL;
5853 34959 : fexpr = (FuncExpr *) rtfunc->funcexpr;
5854 :
5855 34959 : func_oid = fexpr->funcid;
5856 :
5857 : /*
5858 : * Refuse to inline if the arguments contain any volatile functions or
5859 : * sub-selects. Volatile functions are rejected because inlining may
5860 : * result in the arguments being evaluated multiple times, risking a
5861 : * change in behavior. Sub-selects are rejected partly for implementation
5862 : * reasons (pushing them down another level might change their behavior)
5863 : * and partly because they're likely to be expensive and so multiple
5864 : * evaluation would be bad.
5865 : */
5866 69800 : if (contain_volatile_functions((Node *) fexpr->args) ||
5867 34841 : contain_subplans((Node *) fexpr->args))
5868 283 : return NULL;
5869 :
5870 : /* Check permission to call function (fail later, if not) */
5871 34676 : if (object_aclcheck(ProcedureRelationId, func_oid, GetUserId(), ACL_EXECUTE) != ACLCHECK_OK)
5872 6 : return NULL;
5873 :
5874 : /* Check whether a plugin wants to hook function entry/exit */
5875 34670 : if (FmgrHookIsNeeded(func_oid))
5876 0 : return NULL;
5877 :
5878 : /*
5879 : * OK, let's take a look at the function's pg_proc entry.
5880 : */
5881 34670 : func_tuple = SearchSysCache1(PROCOID, ObjectIdGetDatum(func_oid));
5882 34670 : if (!HeapTupleIsValid(func_tuple))
5883 0 : elog(ERROR, "cache lookup failed for function %u", func_oid);
5884 34670 : funcform = (Form_pg_proc) GETSTRUCT(func_tuple);
5885 :
5886 : /*
5887 : * If the function SETs any configuration parameters, inlining would cause
5888 : * us to miss making those changes.
5889 : */
5890 34670 : if (!heap_attisnull(func_tuple, Anum_pg_proc_proconfig, NULL))
5891 : {
5892 8 : ReleaseSysCache(func_tuple);
5893 8 : return NULL;
5894 : }
5895 :
5896 : /*
5897 : * Make a temporary memory context, so that we don't leak all the stuff
5898 : * that parsing and rewriting might create. If we succeed, we'll copy
5899 : * just the finished query tree back up to the caller's context.
5900 : */
5901 34662 : mycxt = AllocSetContextCreate(CurrentMemoryContext,
5902 : "inline_function_in_from",
5903 : ALLOCSET_DEFAULT_SIZES);
5904 34662 : oldcxt = MemoryContextSwitchTo(mycxt);
5905 :
5906 : /* Fetch the function body */
5907 34662 : tmp = SysCacheGetAttrNotNull(PROCOID, func_tuple, Anum_pg_proc_prosrc);
5908 34662 : src = TextDatumGetCString(tmp);
5909 :
5910 : /*
5911 : * If the function has an attached support function that can handle
5912 : * SupportRequestInlineInFrom, then attempt to inline with that.
5913 : */
5914 34662 : if (funcform->prosupport)
5915 : {
5916 : SupportRequestInlineInFrom req;
5917 :
5918 12947 : req.type = T_SupportRequestInlineInFrom;
5919 12947 : req.root = root;
5920 12947 : req.rtfunc = rtfunc;
5921 12947 : req.proc = func_tuple;
5922 :
5923 : querytree = (Query *)
5924 12947 : DatumGetPointer(OidFunctionCall1(funcform->prosupport,
5925 : PointerGetDatum(&req)));
5926 : }
5927 :
5928 : /*
5929 : * Setup error traceback support for ereport(). This is so that we can
5930 : * finger the function that bad information came from. We don't install
5931 : * this while running the support function, since it'd be likely to do the
5932 : * wrong thing: any parse errors reported during that are very likely not
5933 : * against the raw function source text.
5934 : */
5935 34662 : callback_arg.proname = NameStr(funcform->proname);
5936 34662 : callback_arg.prosrc = src;
5937 :
5938 34662 : sqlerrcontext.callback = sql_inline_error_callback;
5939 34662 : sqlerrcontext.arg = &callback_arg;
5940 34662 : sqlerrcontext.previous = error_context_stack;
5941 34662 : error_context_stack = &sqlerrcontext;
5942 :
5943 : /*
5944 : * If SupportRequestInlineInFrom didn't work, try our built-in inlining
5945 : * mechanism.
5946 : */
5947 34662 : if (!querytree)
5948 34642 : querytree = inline_sql_function_in_from(root, rtfunc, fexpr,
5949 : func_tuple, funcform, src);
5950 :
5951 34658 : if (!querytree)
5952 34453 : goto fail; /* no luck there either, fail */
5953 :
5954 : /*
5955 : * The result had better be a SELECT Query.
5956 : */
5957 : Assert(IsA(querytree, Query));
5958 : Assert(querytree->commandType == CMD_SELECT);
5959 :
5960 : /*
5961 : * Looks good --- substitute parameters into the query.
5962 : */
5963 205 : querytree = substitute_actual_parameters_in_from(querytree,
5964 205 : funcform->pronargs,
5965 : fexpr->args);
5966 :
5967 : /*
5968 : * Copy the modified query out of the temporary memory context, and clean
5969 : * up.
5970 : */
5971 205 : MemoryContextSwitchTo(oldcxt);
5972 :
5973 205 : querytree = copyObject(querytree);
5974 :
5975 205 : MemoryContextDelete(mycxt);
5976 205 : error_context_stack = sqlerrcontext.previous;
5977 205 : ReleaseSysCache(func_tuple);
5978 :
5979 : /*
5980 : * We don't have to fix collations here because the upper query is already
5981 : * parsed, ie, the collations in the RTE are what count.
5982 : */
5983 :
5984 : /*
5985 : * Since there is now no trace of the function in the plan tree, we must
5986 : * explicitly record the plan's dependency on the function.
5987 : */
5988 205 : record_plan_function_dependency(root, func_oid);
5989 :
5990 : /*
5991 : * We must also notice if the inserted query adds a dependency on the
5992 : * calling role due to RLS quals.
5993 : */
5994 205 : if (querytree->hasRowSecurity)
5995 60 : root->glob->dependsOnRole = true;
5996 :
5997 205 : return querytree;
5998 :
5999 : /* Here if func is not inlinable: release temp memory and return NULL */
6000 34453 : fail:
6001 34453 : MemoryContextSwitchTo(oldcxt);
6002 34453 : MemoryContextDelete(mycxt);
6003 34453 : error_context_stack = sqlerrcontext.previous;
6004 34453 : ReleaseSysCache(func_tuple);
6005 :
6006 34453 : return NULL;
6007 : }
6008 :
6009 : /*
6010 : * inline_sql_function_in_from
6011 : *
6012 : * This implements inline_function_in_from for SQL-language functions.
6013 : * Returns NULL if the function couldn't be inlined.
6014 : *
6015 : * The division of labor between here and inline_function_in_from is based
6016 : * on the rule that inline_function_in_from should make all checks that are
6017 : * certain to be required in both this case and the support-function case.
6018 : * Support functions might also want to make checks analogous to the ones
6019 : * made here, but then again they might not, or they might just assume that
6020 : * the function they are attached to can validly be inlined.
6021 : */
6022 : static Query *
6023 34642 : inline_sql_function_in_from(PlannerInfo *root,
6024 : RangeTblFunction *rtfunc,
6025 : FuncExpr *fexpr,
6026 : HeapTuple func_tuple,
6027 : Form_pg_proc funcform,
6028 : const char *src)
6029 : {
6030 : Datum sqlbody;
6031 : bool isNull;
6032 : List *querytree_list;
6033 : Query *querytree;
6034 : TypeFuncClass functypclass;
6035 : TupleDesc rettupdesc;
6036 :
6037 : /*
6038 : * The function must be declared to return a set, else inlining would
6039 : * change the results if the contained SELECT didn't return exactly one
6040 : * row.
6041 : */
6042 34642 : if (!fexpr->funcretset)
6043 5763 : return NULL;
6044 :
6045 : /*
6046 : * Forget it if the function is not SQL-language or has other showstopper
6047 : * properties. In particular it mustn't be declared STRICT, since we
6048 : * couldn't enforce that. It also mustn't be VOLATILE, because that is
6049 : * supposed to cause it to be executed with its own snapshot, rather than
6050 : * sharing the snapshot of the calling query. We also disallow returning
6051 : * SETOF VOID, because inlining would result in exposing the actual result
6052 : * of the function's last SELECT, which should not happen in that case.
6053 : * (Rechecking prokind, proretset, and pronargs is just paranoia.)
6054 : */
6055 28879 : if (funcform->prolang != SQLlanguageId ||
6056 768 : funcform->prokind != PROKIND_FUNCTION ||
6057 768 : funcform->proisstrict ||
6058 718 : funcform->provolatile == PROVOLATILE_VOLATILE ||
6059 194 : funcform->prorettype == VOIDOID ||
6060 189 : funcform->prosecdef ||
6061 189 : !funcform->proretset ||
6062 189 : list_length(fexpr->args) != funcform->pronargs)
6063 28690 : return NULL;
6064 :
6065 : /* If we have prosqlbody, pay attention to that not prosrc */
6066 189 : sqlbody = SysCacheGetAttr(PROCOID,
6067 : func_tuple,
6068 : Anum_pg_proc_prosqlbody,
6069 : &isNull);
6070 189 : if (!isNull)
6071 : {
6072 : Node *n;
6073 :
6074 10 : n = stringToNode(TextDatumGetCString(sqlbody));
6075 10 : if (IsA(n, List))
6076 10 : querytree_list = linitial_node(List, castNode(List, n));
6077 : else
6078 0 : querytree_list = list_make1(n);
6079 10 : if (list_length(querytree_list) != 1)
6080 0 : return NULL;
6081 10 : querytree = linitial(querytree_list);
6082 :
6083 : /* Acquire necessary locks, then apply rewriter. */
6084 10 : AcquireRewriteLocks(querytree, true, false);
6085 10 : querytree_list = pg_rewrite_query(querytree);
6086 10 : if (list_length(querytree_list) != 1)
6087 0 : return NULL;
6088 10 : querytree = linitial(querytree_list);
6089 : }
6090 : else
6091 : {
6092 : SQLFunctionParseInfoPtr pinfo;
6093 : List *raw_parsetree_list;
6094 :
6095 : /*
6096 : * Set up to handle parameters while parsing the function body. We
6097 : * can use the FuncExpr just created as the input for
6098 : * prepare_sql_fn_parse_info.
6099 : */
6100 179 : pinfo = prepare_sql_fn_parse_info(func_tuple,
6101 : (Node *) fexpr,
6102 : fexpr->inputcollid);
6103 :
6104 : /*
6105 : * Parse, analyze, and rewrite (unlike inline_function(), we can't
6106 : * skip rewriting here). We can fail as soon as we find more than one
6107 : * query, though.
6108 : */
6109 179 : raw_parsetree_list = pg_parse_query(src);
6110 179 : if (list_length(raw_parsetree_list) != 1)
6111 0 : return NULL;
6112 :
6113 179 : querytree_list = pg_analyze_and_rewrite_withcb(linitial(raw_parsetree_list),
6114 : src,
6115 : (ParserSetupHook) sql_fn_parser_setup,
6116 : pinfo, NULL);
6117 179 : if (list_length(querytree_list) != 1)
6118 0 : return NULL;
6119 179 : querytree = linitial(querytree_list);
6120 : }
6121 :
6122 : /*
6123 : * Also resolve the actual function result tupdesc, if composite. If we
6124 : * have a coldeflist, believe that; otherwise use get_expr_result_type.
6125 : * (This logic should match ExecInitFunctionScan.)
6126 : */
6127 189 : if (rtfunc->funccolnames != NIL)
6128 : {
6129 19 : functypclass = TYPEFUNC_RECORD;
6130 19 : rettupdesc = BuildDescFromLists(rtfunc->funccolnames,
6131 19 : rtfunc->funccoltypes,
6132 19 : rtfunc->funccoltypmods,
6133 19 : rtfunc->funccolcollations);
6134 : }
6135 : else
6136 170 : functypclass = get_expr_result_type((Node *) fexpr, NULL, &rettupdesc);
6137 :
6138 : /*
6139 : * The single command must be a plain SELECT.
6140 : */
6141 189 : if (!IsA(querytree, Query) ||
6142 189 : querytree->commandType != CMD_SELECT)
6143 0 : return NULL;
6144 :
6145 : /*
6146 : * Make sure the function (still) returns what it's declared to. This
6147 : * will raise an error if wrong, but that's okay since the function would
6148 : * fail at runtime anyway. Note that check_sql_fn_retval will also insert
6149 : * coercions if needed to make the tlist expression(s) match the declared
6150 : * type of the function. We also ask it to insert dummy NULL columns for
6151 : * any dropped columns in rettupdesc, so that the elements of the modified
6152 : * tlist match up to the attribute numbers.
6153 : *
6154 : * If the function returns a composite type, don't inline unless the check
6155 : * shows it's returning a whole tuple result; otherwise what it's
6156 : * returning is a single composite column which is not what we need.
6157 : */
6158 189 : if (!check_sql_fn_retval(list_make1(querytree_list),
6159 : fexpr->funcresulttype, rettupdesc,
6160 189 : funcform->prokind,
6161 75 : true) &&
6162 75 : (functypclass == TYPEFUNC_COMPOSITE ||
6163 75 : functypclass == TYPEFUNC_COMPOSITE_DOMAIN ||
6164 : functypclass == TYPEFUNC_RECORD))
6165 0 : return NULL; /* reject not-whole-tuple-result cases */
6166 :
6167 : /*
6168 : * check_sql_fn_retval might've inserted a projection step, but that's
6169 : * fine; just make sure we use the upper Query.
6170 : */
6171 185 : querytree = linitial_node(Query, querytree_list);
6172 :
6173 185 : return querytree;
6174 : }
6175 :
6176 : /*
6177 : * Replace Param nodes by appropriate actual parameters
6178 : *
6179 : * This is just enough different from substitute_actual_parameters()
6180 : * that it needs its own code.
6181 : */
6182 : static Query *
6183 205 : substitute_actual_parameters_in_from(Query *expr, int nargs, List *args)
6184 : {
6185 : substitute_actual_parameters_in_from_context context;
6186 :
6187 205 : context.nargs = nargs;
6188 205 : context.args = args;
6189 205 : context.sublevels_up = 1;
6190 :
6191 205 : return query_tree_mutator(expr,
6192 : substitute_actual_parameters_in_from_mutator,
6193 : &context,
6194 : 0);
6195 : }
6196 :
6197 : static Node *
6198 7695 : substitute_actual_parameters_in_from_mutator(Node *node,
6199 : substitute_actual_parameters_in_from_context *context)
6200 : {
6201 : Node *result;
6202 :
6203 7695 : if (node == NULL)
6204 4480 : return NULL;
6205 3215 : if (IsA(node, Query))
6206 : {
6207 125 : context->sublevels_up++;
6208 125 : result = (Node *) query_tree_mutator((Query *) node,
6209 : substitute_actual_parameters_in_from_mutator,
6210 : context,
6211 : 0);
6212 125 : context->sublevels_up--;
6213 125 : return result;
6214 : }
6215 3090 : if (IsA(node, Param))
6216 : {
6217 95 : Param *param = (Param *) node;
6218 :
6219 95 : if (param->paramkind == PARAM_EXTERN)
6220 : {
6221 95 : if (param->paramid <= 0 || param->paramid > context->nargs)
6222 0 : elog(ERROR, "invalid paramid: %d", param->paramid);
6223 :
6224 : /*
6225 : * Since the parameter is being inserted into a subquery, we must
6226 : * adjust levels.
6227 : */
6228 95 : result = copyObject(list_nth(context->args, param->paramid - 1));
6229 95 : IncrementVarSublevelsUp(result, context->sublevels_up, 0);
6230 95 : return result;
6231 : }
6232 : }
6233 2995 : return expression_tree_mutator(node,
6234 : substitute_actual_parameters_in_from_mutator,
6235 : context);
6236 : }
6237 :
6238 : /*
6239 : * pull_paramids
6240 : * Returns a Bitmapset containing the paramids of all Params in 'expr'.
6241 : */
6242 : Bitmapset *
6243 1475 : pull_paramids(Expr *expr)
6244 : {
6245 1475 : Bitmapset *result = NULL;
6246 :
6247 1475 : (void) pull_paramids_walker((Node *) expr, &result);
6248 :
6249 1475 : return result;
6250 : }
6251 :
6252 : static bool
6253 3306 : pull_paramids_walker(Node *node, Bitmapset **context)
6254 : {
6255 3306 : if (node == NULL)
6256 10 : return false;
6257 3296 : if (IsA(node, Param))
6258 : {
6259 1526 : Param *param = (Param *) node;
6260 :
6261 1526 : *context = bms_add_member(*context, param->paramid);
6262 1526 : return false;
6263 : }
6264 1770 : return expression_tree_walker(node, pull_paramids_walker, context);
6265 : }
6266 :
6267 : /*
6268 : * Build ScalarArrayOpExpr on top of 'exprs.' 'haveNonConst' indicates
6269 : * whether at least one of the expressions is not Const. When it's false,
6270 : * the array constant is built directly; otherwise, we have to build a child
6271 : * ArrayExpr. The 'exprs' list gets freed if not directly used in the output
6272 : * expression tree.
6273 : */
6274 : ScalarArrayOpExpr *
6275 2933 : make_SAOP_expr(Oid oper, Node *leftexpr, Oid coltype, Oid arraycollid,
6276 : Oid inputcollid, List *exprs, bool haveNonConst)
6277 : {
6278 2933 : Node *arrayNode = NULL;
6279 2933 : ScalarArrayOpExpr *saopexpr = NULL;
6280 2933 : Oid arraytype = get_array_type(coltype);
6281 :
6282 2933 : if (!OidIsValid(arraytype))
6283 0 : return NULL;
6284 :
6285 : /*
6286 : * Assemble an array from the list of constants. It seems more profitable
6287 : * to build a const array. But in the presence of other nodes, we don't
6288 : * have a specific value here and must employ an ArrayExpr instead.
6289 : */
6290 2933 : if (haveNonConst)
6291 : {
6292 84 : ArrayExpr *arrayExpr = makeNode(ArrayExpr);
6293 :
6294 : /* array_collid will be set by parse_collate.c */
6295 84 : arrayExpr->element_typeid = coltype;
6296 84 : arrayExpr->array_typeid = arraytype;
6297 84 : arrayExpr->multidims = false;
6298 84 : arrayExpr->elements = exprs;
6299 84 : arrayExpr->location = -1;
6300 :
6301 84 : arrayNode = (Node *) arrayExpr;
6302 : }
6303 : else
6304 : {
6305 : int16 typlen;
6306 : bool typbyval;
6307 : char typalign;
6308 : Datum *elems;
6309 : bool *nulls;
6310 2849 : int i = 0;
6311 : ArrayType *arrayConst;
6312 2849 : int dims[1] = {list_length(exprs)};
6313 2849 : int lbs[1] = {1};
6314 :
6315 2849 : get_typlenbyvalalign(coltype, &typlen, &typbyval, &typalign);
6316 :
6317 2849 : elems = palloc_array(Datum, list_length(exprs));
6318 2849 : nulls = palloc_array(bool, list_length(exprs));
6319 11801 : foreach_node(Const, value, exprs)
6320 : {
6321 6103 : elems[i] = value->constvalue;
6322 6103 : nulls[i++] = value->constisnull;
6323 : }
6324 :
6325 2849 : arrayConst = construct_md_array(elems, nulls, 1, dims, lbs,
6326 : coltype, typlen, typbyval, typalign);
6327 2849 : arrayNode = (Node *) makeConst(arraytype, -1, arraycollid,
6328 : -1, PointerGetDatum(arrayConst),
6329 : false, false);
6330 :
6331 2849 : pfree(elems);
6332 2849 : pfree(nulls);
6333 2849 : list_free(exprs);
6334 : }
6335 :
6336 : /* Build the SAOP expression node */
6337 2933 : saopexpr = makeNode(ScalarArrayOpExpr);
6338 2933 : saopexpr->opno = oper;
6339 2933 : saopexpr->opfuncid = get_opcode(oper);
6340 2933 : saopexpr->hashfuncid = InvalidOid;
6341 2933 : saopexpr->negfuncid = InvalidOid;
6342 2933 : saopexpr->useOr = true;
6343 2933 : saopexpr->inputcollid = inputcollid;
6344 2933 : saopexpr->args = list_make2(leftexpr, arrayNode);
6345 2933 : saopexpr->location = -1;
6346 :
6347 2933 : return saopexpr;
6348 : }
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