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 8746 : contain_agg_clause(Node *clause)
195 : {
196 8746 : return contain_agg_clause_walker(clause, NULL);
197 : }
198 :
199 : static bool
200 11022 : contain_agg_clause_walker(Node *node, void *context)
201 : {
202 11022 : if (node == NULL)
203 30 : return false;
204 10992 : if (IsA(node, Aggref))
205 : {
206 : Assert(((Aggref *) node)->agglevelsup == 0);
207 793 : return true; /* abort the tree traversal and return true */
208 : }
209 10199 : 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 10174 : 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 2222 : find_window_functions(Node *clause, Index maxWinRef)
245 : {
246 2222 : WindowFuncLists *lists = palloc_object(WindowFuncLists);
247 :
248 2222 : lists->numWindowFuncs = 0;
249 2222 : lists->maxWinRef = maxWinRef;
250 2222 : lists->windowFuncs = (List **) palloc0((maxWinRef + 1) * sizeof(List *));
251 2222 : (void) find_window_functions_walker(clause, lists);
252 2222 : return lists;
253 : }
254 :
255 : static bool
256 18720 : find_window_functions_walker(Node *node, WindowFuncLists *lists)
257 : {
258 18720 : if (node == NULL)
259 179 : return false;
260 18541 : if (IsA(node, WindowFunc))
261 : {
262 3077 : WindowFunc *wfunc = (WindowFunc *) node;
263 :
264 : /* winref is unsigned, so one-sided test is OK */
265 3077 : if (wfunc->winref > lists->maxWinRef)
266 0 : elog(ERROR, "WindowFunc contains out-of-range winref %u",
267 : wfunc->winref);
268 :
269 6154 : lists->windowFuncs[wfunc->winref] =
270 3077 : lappend(lists->windowFuncs[wfunc->winref], wfunc);
271 3077 : 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 3077 : return false;
280 : }
281 : Assert(!IsA(node, SubLink));
282 15464 : 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 328255 : expression_returns_set_rows(PlannerInfo *root, Node *clause)
303 : {
304 328255 : if (clause == NULL)
305 0 : return 1.0;
306 328255 : if (IsA(clause, FuncExpr))
307 : {
308 47300 : FuncExpr *expr = (FuncExpr *) clause;
309 :
310 47300 : if (expr->funcretset)
311 40776 : return clamp_row_est(get_function_rows(root, expr->funcid, clause));
312 : }
313 287479 : 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 287474 : 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 41566 : contain_subplans(Node *clause)
344 : {
345 41566 : return contain_subplans_walker(clause, NULL);
346 : }
347 :
348 : static bool
349 173676 : contain_subplans_walker(Node *node, void *context)
350 : {
351 173676 : if (node == NULL)
352 5016 : return false;
353 168660 : if (IsA(node, SubPlan) ||
354 168581 : IsA(node, AlternativeSubPlan) ||
355 168581 : IsA(node, SubLink))
356 249 : return true; /* abort the tree traversal and return true */
357 168411 : 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 119385 : contain_mutable_functions(Node *clause)
384 : {
385 119385 : return contain_mutable_functions_walker(clause, NULL);
386 : }
387 :
388 : static bool
389 90190 : contain_mutable_functions_checker(Oid func_id, void *context)
390 : {
391 90190 : return (func_volatile(func_id) != PROVOLATILE_IMMUTABLE);
392 : }
393 :
394 : static bool
395 323924 : contain_mutable_functions_walker(Node *node, void *context)
396 : {
397 323924 : if (node == NULL)
398 1871 : return false;
399 : /* Check for mutable functions in node itself */
400 322053 : if (check_functions_in_node(node, contain_mutable_functions_checker,
401 : context))
402 6006 : return true;
403 :
404 316047 : 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 315903 : 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 315795 : if (IsA(node, SQLValueFunction))
451 : {
452 : /* all variants of SQLValueFunction are stable */
453 259 : return true;
454 : }
455 :
456 315536 : 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 315536 : 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 315536 : 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 2517 : contain_mutable_functions_after_planning(Expr *expr)
504 : {
505 : /* We assume here that expression_planner() won't scribble on its input */
506 2517 : expr = expression_planner(expr);
507 :
508 : /* Now we can search for non-immutable functions */
509 2517 : 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 2648712 : contain_volatile_functions(Node *clause)
552 : {
553 2648712 : return contain_volatile_functions_walker(clause, NULL);
554 : }
555 :
556 : static bool
557 752978 : contain_volatile_functions_checker(Oid func_id, void *context)
558 : {
559 752978 : return (func_volatile(func_id) == PROVOLATILE_VOLATILE);
560 : }
561 :
562 : static bool
563 6104707 : contain_volatile_functions_walker(Node *node, void *context)
564 : {
565 6104707 : if (node == NULL)
566 185451 : return false;
567 : /* Check for volatile functions in node itself */
568 5919256 : if (check_functions_in_node(node, contain_volatile_functions_checker,
569 : context))
570 1603 : return true;
571 :
572 5917653 : if (IsA(node, NextValueExpr))
573 : {
574 : /* NextValueExpr is volatile */
575 28 : return true;
576 : }
577 :
578 5917625 : if (IsA(node, RestrictInfo))
579 : {
580 1011321 : 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 1011321 : if (rinfo->has_volatile == VOLATILITY_NOVOLATILE)
589 608991 : return false;
590 402330 : else if (rinfo->has_volatile == VOLATILITY_VOLATILE)
591 54 : return true;
592 : else
593 : {
594 : bool hasvolatile;
595 :
596 402276 : hasvolatile = contain_volatile_functions_walker((Node *) rinfo->clause,
597 : context);
598 402276 : if (hasvolatile)
599 98 : rinfo->has_volatile = VOLATILITY_VOLATILE;
600 : else
601 402178 : rinfo->has_volatile = VOLATILITY_NOVOLATILE;
602 :
603 402276 : return hasvolatile;
604 : }
605 : }
606 :
607 4906304 : if (IsA(node, PathTarget))
608 : {
609 278714 : PathTarget *target = (PathTarget *) node;
610 :
611 : /*
612 : * We also do caching for PathTarget the same as we do above for
613 : * RestrictInfos.
614 : */
615 278714 : if (target->has_volatile_expr == VOLATILITY_NOVOLATILE)
616 231208 : return false;
617 47506 : else if (target->has_volatile_expr == VOLATILITY_VOLATILE)
618 0 : return true;
619 : else
620 : {
621 : bool hasvolatile;
622 :
623 47506 : hasvolatile = contain_volatile_functions_walker((Node *) target->exprs,
624 : context);
625 :
626 47506 : if (hasvolatile)
627 0 : target->has_volatile_expr = VOLATILITY_VOLATILE;
628 : else
629 47506 : target->has_volatile_expr = VOLATILITY_NOVOLATILE;
630 :
631 47506 : 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 4627590 : 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 4622171 : 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
672 875 : contain_volatile_functions_after_planning(Expr *expr)
673 : {
674 : /* We assume here that expression_planner() won't scribble on its input */
675 875 : expr = expression_planner(expr);
676 :
677 : /* Now we can search for volatile functions */
678 867 : 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 257702 : max_parallel_hazard(Query *parse)
748 : {
749 : max_parallel_hazard_context context;
750 :
751 257702 : context.max_hazard = PROPARALLEL_SAFE;
752 257702 : context.max_interesting = PROPARALLEL_UNSAFE;
753 257702 : context.safe_param_ids = NIL;
754 257702 : (void) max_parallel_hazard_walker((Node *) parse, &context);
755 257702 : 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 1892880 : 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 1892880 : if (root->glob->maxParallelHazard == PROPARALLEL_SAFE &&
779 1146835 : root->glob->paramExecTypes == NIL)
780 1119901 : return true;
781 : /* Else use max_parallel_hazard's search logic, but stop on RESTRICTED */
782 772979 : context.max_hazard = PROPARALLEL_SAFE;
783 772979 : context.max_interesting = PROPARALLEL_RESTRICTED;
784 772979 : 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 1887604 : for (proot = root; proot != NULL; proot = proot->parent_root)
792 : {
793 1168377 : foreach(l, proot->init_plans)
794 : {
795 53752 : SubPlan *initsubplan = (SubPlan *) lfirst(l);
796 :
797 53752 : context.safe_param_ids = list_concat(context.safe_param_ids,
798 53752 : initsubplan->setParam);
799 : }
800 : }
801 :
802 772979 : return !max_parallel_hazard_walker(node, &context);
803 : }
804 :
805 : /* core logic for all parallel-hazard checks */
806 : static bool
807 1293142 : max_parallel_hazard_test(char proparallel, max_parallel_hazard_context *context)
808 : {
809 1293142 : switch (proparallel)
810 : {
811 1085568 : case PROPARALLEL_SAFE:
812 : /* nothing to see here, move along */
813 1085568 : break;
814 156456 : case PROPARALLEL_RESTRICTED:
815 : /* increase max_hazard to RESTRICTED */
816 : Assert(context->max_hazard != PROPARALLEL_UNSAFE);
817 156456 : context->max_hazard = proparallel;
818 : /* done if we are not expecting any unsafe functions */
819 156456 : if (context->max_interesting == proparallel)
820 77471 : return true;
821 78985 : break;
822 51118 : case PROPARALLEL_UNSAFE:
823 51118 : context->max_hazard = proparallel;
824 : /* we're always done at the first unsafe construct */
825 51118 : return true;
826 0 : default:
827 0 : elog(ERROR, "unrecognized proparallel value \"%c\"", proparallel);
828 : break;
829 : }
830 1164553 : return false;
831 : }
832 :
833 : /* check_functions_in_node callback */
834 : static bool
835 1178621 : max_parallel_hazard_checker(Oid func_id, void *context)
836 : {
837 1178621 : return max_parallel_hazard_test(func_parallel(func_id),
838 : (max_parallel_hazard_context *) context);
839 : }
840 :
841 : static bool
842 16890784 : max_parallel_hazard_walker(Node *node, max_parallel_hazard_context *context)
843 : {
844 16890784 : if (node == NULL)
845 4704969 : return false;
846 :
847 : /* Check for hazardous functions in node itself */
848 12185815 : if (check_functions_in_node(node, max_parallel_hazard_checker,
849 : context))
850 67253 : 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 12118562 : if (IsA(node, CoerceToDomain))
864 : {
865 15796 : if (max_parallel_hazard_test(PROPARALLEL_RESTRICTED, context))
866 4336 : return true;
867 : }
868 :
869 12102766 : 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 12102446 : else if (IsA(node, WindowFunc))
884 : {
885 5156 : if (max_parallel_hazard_test(PROPARALLEL_RESTRICTED, context))
886 2283 : return true;
887 : }
888 :
889 : /*
890 : * As a notational convenience for callers, look through RestrictInfo.
891 : */
892 12097290 : else if (IsA(node, RestrictInfo))
893 : {
894 199273 : RestrictInfo *rinfo = (RestrictInfo *) node;
895 :
896 199273 : 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 11898017 : else if (IsA(node, SubLink))
904 : {
905 34741 : 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 11863276 : else if (IsA(node, SubPlan))
916 : {
917 24816 : SubPlan *subplan = (SubPlan *) node;
918 : List *save_safe_param_ids;
919 :
920 49367 : if (!subplan->parallel_safe &&
921 24551 : max_parallel_hazard_test(PROPARALLEL_RESTRICTED, context))
922 24551 : 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 11838460 : else if (IsA(node, Param))
945 : {
946 84226 : Param *param = (Param *) node;
947 :
948 84226 : if (param->paramkind == PARAM_EXTERN)
949 42268 : return false;
950 :
951 41958 : if (param->paramkind != PARAM_EXEC ||
952 37794 : !list_member_int(context->safe_param_ids, param->paramid))
953 : {
954 33957 : if (max_parallel_hazard_test(PROPARALLEL_RESTRICTED, context))
955 29846 : return true;
956 : }
957 12112 : 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 11754234 : else if (IsA(node, Query))
966 : {
967 343584 : Query *query = (Query *) node;
968 :
969 : /* SELECT FOR UPDATE/SHARE must be treated as unsafe */
970 343584 : if (query->rowMarks != NULL)
971 : {
972 3849 : context->max_hazard = PROPARALLEL_UNSAFE;
973 3849 : return true;
974 : }
975 :
976 : /* Recurse into subselects */
977 339735 : return query_tree_walker(query,
978 : max_parallel_hazard_walker,
979 : context, 0);
980 : }
981 :
982 : /* Recurse to check arguments */
983 11459724 : 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 1901 : contain_nonstrict_functions(Node *clause)
1007 : {
1008 1901 : return contain_nonstrict_functions_walker(clause, NULL);
1009 : }
1010 :
1011 : static bool
1012 1962 : contain_nonstrict_functions_checker(Oid func_id, void *context)
1013 : {
1014 1962 : return !func_strict(func_id);
1015 : }
1016 :
1017 : static bool
1018 6657 : contain_nonstrict_functions_walker(Node *node, void *context)
1019 : {
1020 6657 : if (node == NULL)
1021 0 : return false;
1022 6657 : if (IsA(node, Aggref))
1023 : {
1024 : /* an aggregate could return non-null with null input */
1025 0 : return true;
1026 : }
1027 6657 : 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 6657 : if (IsA(node, WindowFunc))
1036 : {
1037 : /* a window function could return non-null with null input */
1038 0 : return true;
1039 : }
1040 6657 : 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 6657 : if (IsA(node, DistinctExpr))
1055 : {
1056 : /* IS DISTINCT FROM is inherently non-strict */
1057 0 : return true;
1058 : }
1059 6657 : if (IsA(node, NullIfExpr))
1060 : {
1061 : /* NULLIF is inherently non-strict */
1062 0 : return true;
1063 : }
1064 6657 : 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 6642 : if (IsA(node, SubLink))
1079 : {
1080 : /* In some cases a sublink might be strict, but in general not */
1081 10 : return true;
1082 : }
1083 6632 : if (IsA(node, SubPlan))
1084 0 : return true;
1085 6632 : if (IsA(node, AlternativeSubPlan))
1086 0 : return true;
1087 6632 : if (IsA(node, FieldStore))
1088 0 : return true;
1089 6632 : 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 875 : return contain_nonstrict_functions_walker((Node *) ((CoerceViaIO *) node)->arg,
1097 : context);
1098 : }
1099 5757 : 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 5757 : if (IsA(node, CaseExpr))
1110 52 : return true;
1111 5705 : if (IsA(node, ArrayExpr))
1112 0 : return true;
1113 5705 : if (IsA(node, RowExpr))
1114 2 : return true;
1115 5703 : if (IsA(node, RowCompareExpr))
1116 0 : return true;
1117 5703 : if (IsA(node, CoalesceExpr))
1118 211 : return true;
1119 5492 : if (IsA(node, MinMaxExpr))
1120 50 : return true;
1121 5442 : if (IsA(node, XmlExpr))
1122 0 : return true;
1123 5442 : if (IsA(node, NullTest))
1124 20 : return true;
1125 5422 : if (IsA(node, BooleanTest))
1126 0 : return true;
1127 5422 : if (IsA(node, JsonConstructorExpr))
1128 10 : return true;
1129 :
1130 : /* Check other function-containing nodes */
1131 5412 : if (check_functions_in_node(node, contain_nonstrict_functions_checker,
1132 : context))
1133 0 : return true;
1134 :
1135 5412 : 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 2535 : contain_context_dependent_node(Node *clause)
1195 : {
1196 2535 : int flags = 0;
1197 :
1198 2535 : return contain_context_dependent_node_walker(clause, &flags);
1199 : }
1200 :
1201 : #define CCDN_CASETESTEXPR_OK 0x0001 /* CaseTestExpr okay here? */
1202 :
1203 : static bool
1204 7799 : contain_context_dependent_node_walker(Node *node, int *flags)
1205 : {
1206 7799 : if (node == NULL)
1207 136 : return false;
1208 7663 : if (IsA(node, CaseTestExpr))
1209 5 : return !(*flags & CCDN_CASETESTEXPR_OK);
1210 7658 : 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 7658 : 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 7658 : 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 6698 : contain_leaked_vars(Node *clause)
1279 : {
1280 6698 : return contain_leaked_vars_walker(clause, NULL);
1281 : }
1282 :
1283 : static bool
1284 6598 : contain_leaked_vars_checker(Oid func_id, void *context)
1285 : {
1286 6598 : return !get_func_leakproof(func_id);
1287 : }
1288 :
1289 : static bool
1290 15195 : contain_leaked_vars_walker(Node *node, void *context)
1291 : {
1292 15195 : if (node == NULL)
1293 0 : return false;
1294 :
1295 15195 : switch (nodeTag(node))
1296 : {
1297 8537 : 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 8537 : break;
1322 :
1323 6598 : 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 6598 : if (check_functions_in_node(node, contain_leaked_vars_checker,
1336 2390 : context) &&
1337 2390 : contain_var_clause(node))
1338 2346 : return true;
1339 4252 : 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 12789 : 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 82083 : find_nonnullable_rels(Node *clause)
1477 : {
1478 82083 : return find_nonnullable_rels_walker(clause, true);
1479 : }
1480 :
1481 : static Relids
1482 544127 : find_nonnullable_rels_walker(Node *node, bool top_level)
1483 : {
1484 544127 : Relids result = NULL;
1485 : ListCell *l;
1486 :
1487 544127 : if (node == NULL)
1488 5141 : return NULL;
1489 538986 : if (IsA(node, Var))
1490 : {
1491 173559 : Var *var = (Var *) node;
1492 :
1493 173559 : if (var->varlevelsup == 0)
1494 173559 : result = bms_make_singleton(var->varno);
1495 : }
1496 365427 : 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 524548 : foreach(l, (List *) node)
1508 : {
1509 333462 : result = bms_join(result,
1510 333462 : find_nonnullable_rels_walker(lfirst(l),
1511 : top_level));
1512 : }
1513 : }
1514 174341 : else if (IsA(node, FuncExpr))
1515 : {
1516 6724 : FuncExpr *expr = (FuncExpr *) node;
1517 :
1518 6724 : if (func_strict(expr->funcid))
1519 6570 : result = find_nonnullable_rels_walker((Node *) expr->args, false);
1520 : }
1521 167617 : else if (IsA(node, OpExpr))
1522 : {
1523 97662 : OpExpr *expr = (OpExpr *) node;
1524 :
1525 97662 : set_opfuncid(expr);
1526 97662 : if (func_strict(expr->opfuncid))
1527 97662 : result = find_nonnullable_rels_walker((Node *) expr->args, false);
1528 : }
1529 69955 : else if (IsA(node, ScalarArrayOpExpr))
1530 : {
1531 6371 : ScalarArrayOpExpr *expr = (ScalarArrayOpExpr *) node;
1532 :
1533 6371 : if (is_strict_saop(expr, true))
1534 6371 : result = find_nonnullable_rels_walker((Node *) expr->args, false);
1535 : }
1536 63584 : else if (IsA(node, BoolExpr))
1537 : {
1538 7270 : BoolExpr *expr = (BoolExpr *) node;
1539 :
1540 7270 : 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 9202 : foreach(l, expr->args)
1567 : {
1568 : Relids subresult;
1569 :
1570 7419 : subresult = find_nonnullable_rels_walker(lfirst(l),
1571 : top_level);
1572 7419 : if (result == NULL) /* first subresult? */
1573 3729 : result = subresult;
1574 : else
1575 3690 : 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 7419 : if (bms_is_empty(result))
1582 1946 : break;
1583 : }
1584 3729 : break;
1585 3212 : case NOT_EXPR:
1586 : /* NOT will return null if its arg is null */
1587 3212 : result = find_nonnullable_rels_walker((Node *) expr->args,
1588 : false);
1589 3212 : break;
1590 0 : default:
1591 0 : elog(ERROR, "unrecognized boolop: %d", (int) expr->boolop);
1592 : break;
1593 : }
1594 : }
1595 56314 : else if (IsA(node, RelabelType))
1596 : {
1597 3442 : RelabelType *expr = (RelabelType *) node;
1598 :
1599 3442 : result = find_nonnullable_rels_walker((Node *) expr->arg, top_level);
1600 : }
1601 52872 : 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 52695 : 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 52695 : 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 52695 : 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 52695 : else if (IsA(node, NullTest))
1629 : {
1630 : /* IS NOT NULL can be considered strict, but only at top level */
1631 4278 : NullTest *expr = (NullTest *) node;
1632 :
1633 4278 : if (top_level && expr->nulltesttype == IS_NOT_NULL && !expr->argisrow)
1634 2821 : result = find_nonnullable_rels_walker((Node *) expr->arg, false);
1635 : }
1636 48417 : 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 48308 : 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 48200 : 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 538986 : 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 1170 : find_nonnullable_vars(Node *clause)
1728 : {
1729 1170 : return find_nonnullable_vars_walker(clause, true);
1730 : }
1731 :
1732 : static List *
1733 7723 : find_nonnullable_vars_walker(Node *node, bool top_level)
1734 : {
1735 7723 : List *result = NIL;
1736 : ListCell *l;
1737 :
1738 7723 : if (node == NULL)
1739 35 : return NIL;
1740 7688 : if (IsA(node, Var))
1741 : {
1742 3038 : Var *var = (Var *) node;
1743 :
1744 3038 : if (var->varlevelsup == 0)
1745 3038 : result = mbms_add_member(result,
1746 : var->varno,
1747 3038 : var->varattno - FirstLowInvalidHeapAttributeNumber);
1748 : }
1749 4650 : 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 7435 : foreach(l, (List *) node)
1761 : {
1762 4712 : result = mbms_add_members(result,
1763 4712 : find_nonnullable_vars_walker(lfirst(l),
1764 : top_level));
1765 : }
1766 : }
1767 1927 : 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 1917 : else if (IsA(node, OpExpr))
1775 : {
1776 1558 : OpExpr *expr = (OpExpr *) node;
1777 :
1778 1558 : set_opfuncid(expr);
1779 1558 : if (func_strict(expr->opfuncid))
1780 1558 : 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 7688 : 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 94006 : find_forced_null_vars(Node *node)
1937 : {
1938 94006 : List *result = NIL;
1939 : Var *var;
1940 : ListCell *l;
1941 :
1942 94006 : if (node == NULL)
1943 4431 : return NIL;
1944 : /* Check single-clause cases using subroutine */
1945 89575 : var = find_forced_null_var(node);
1946 89575 : if (var)
1947 : {
1948 1156 : result = mbms_add_member(result,
1949 : var->varno,
1950 1156 : var->varattno - FirstLowInvalidHeapAttributeNumber);
1951 : }
1952 : /* Otherwise, handle AND-conditions */
1953 88419 : 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 89575 : foreach(l, (List *) node)
1960 : {
1961 54738 : result = mbms_add_members(result,
1962 54738 : find_forced_null_vars((Node *) lfirst(l)));
1963 : }
1964 : }
1965 53582 : else if (IsA(node, BoolExpr))
1966 : {
1967 4377 : 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 4377 : 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 89575 : 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 473523 : find_forced_null_var(Node *node)
1998 : {
1999 473523 : if (node == NULL)
2000 0 : return NULL;
2001 473523 : if (IsA(node, NullTest))
2002 : {
2003 : /* check for var IS NULL */
2004 9556 : NullTest *expr = (NullTest *) node;
2005 :
2006 9556 : if (expr->nulltesttype == IS_NULL && !expr->argisrow)
2007 : {
2008 3511 : Var *var = (Var *) expr->arg;
2009 :
2010 3511 : if (var && IsA(var, Var) &&
2011 3403 : var->varlevelsup == 0)
2012 3403 : return var;
2013 : }
2014 : }
2015 463967 : 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 470075 : 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 6371 : is_strict_saop(ScalarArrayOpExpr *expr, bool falseOK)
2272 : {
2273 : Node *rightop;
2274 :
2275 : /* The contained operator must be strict. */
2276 6371 : set_sa_opfuncid(expr);
2277 6371 : if (!func_strict(expr->opfuncid))
2278 0 : return false;
2279 : /* If ANY and falseOK, that's all we need to check. */
2280 6371 : if (expr->useOr && falseOK)
2281 6265 : 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 353047 : is_pseudo_constant_clause_relids(Node *clause, Relids relids)
2354 : {
2355 353047 : if (bms_is_empty(relids) &&
2356 346580 : !contain_volatile_functions(clause))
2357 346580 : return true;
2358 6467 : 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 18536 : CommuteOpExpr(OpExpr *clause)
2393 : {
2394 : Oid opoid;
2395 : Node *temp;
2396 :
2397 : /* Sanity checks: caller is at fault if these fail */
2398 37072 : if (!is_opclause(clause) ||
2399 18536 : list_length(clause->args) != 2)
2400 0 : elog(ERROR, "cannot commute non-binary-operator clause");
2401 :
2402 18536 : opoid = get_commutator(clause->opno);
2403 :
2404 18536 : 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 18536 : clause->opno = opoid;
2412 18536 : clause->opfuncid = InvalidOid;
2413 : /* opresulttype, opretset, opcollid, inputcollid need not change */
2414 :
2415 18536 : temp = linitial(clause->args);
2416 18536 : linitial(clause->args) = lsecond(clause->args);
2417 18536 : lsecond(clause->args) = temp;
2418 18536 : }
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 898914 : eval_const_expressions(PlannerInfo *root, Node *node)
2501 : {
2502 : eval_const_expressions_context context;
2503 :
2504 898914 : if (root)
2505 754808 : context.boundParams = root->glob->boundParams; /* bound Params */
2506 : else
2507 144106 : context.boundParams = NULL;
2508 898914 : context.root = root; /* for inlined-function dependencies */
2509 898914 : context.active_fns = NIL; /* nothing being recursively simplified */
2510 898914 : context.case_val = NULL; /* no CASE being examined */
2511 898914 : context.estimate = false; /* safe transformations only */
2512 898914 : 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 656726 : convert_saop_to_hashed_saop(Node *node)
2534 : {
2535 656726 : (void) convert_saop_to_hashed_saop_walker(node, NULL);
2536 656726 : }
2537 :
2538 : static bool
2539 4828301 : convert_saop_to_hashed_saop_walker(Node *node, void *context)
2540 : {
2541 4828301 : if (node == NULL)
2542 112292 : return false;
2543 :
2544 4716009 : if (IsA(node, ScalarArrayOpExpr))
2545 : {
2546 25575 : ScalarArrayOpExpr *saop = (ScalarArrayOpExpr *) node;
2547 25575 : Expr *arrayarg = (Expr *) lsecond(saop->args);
2548 : Oid lefthashfunc;
2549 : Oid righthashfunc;
2550 :
2551 25575 : if (arrayarg && IsA(arrayarg, Const) &&
2552 13051 : !((Const *) arrayarg)->constisnull)
2553 : {
2554 13026 : if (saop->useOr)
2555 : {
2556 11180 : if (get_op_hash_functions(saop->opno, &lefthashfunc, &righthashfunc) &&
2557 10903 : lefthashfunc == righthashfunc)
2558 : {
2559 10868 : Datum arrdatum = ((Const *) arrayarg)->constvalue;
2560 10868 : ArrayType *arr = (ArrayType *) DatumGetPointer(arrdatum);
2561 : int nitems;
2562 :
2563 : /*
2564 : * Only fill in the hash functions if the array looks
2565 : * large enough for it to be worth hashing instead of
2566 : * doing a linear search.
2567 : */
2568 10868 : nitems = ArrayGetNItems(ARR_NDIM(arr), ARR_DIMS(arr));
2569 :
2570 10868 : if (nitems >= MIN_ARRAY_SIZE_FOR_HASHED_SAOP)
2571 : {
2572 : /* Looks good. Fill in the hash functions */
2573 161 : saop->hashfuncid = lefthashfunc;
2574 : }
2575 12573 : return false;
2576 : }
2577 : }
2578 : else /* !saop->useOr */
2579 : {
2580 1846 : Oid negator = get_negator(saop->opno);
2581 :
2582 : /*
2583 : * Check if this is a NOT IN using an operator whose negator
2584 : * is hashable. If so we can still build a hash table and
2585 : * just ensure the lookup items are not in the hash table.
2586 : */
2587 3692 : if (OidIsValid(negator) &&
2588 1846 : get_op_hash_functions(negator, &lefthashfunc, &righthashfunc) &&
2589 1705 : lefthashfunc == righthashfunc)
2590 : {
2591 1705 : Datum arrdatum = ((Const *) arrayarg)->constvalue;
2592 1705 : ArrayType *arr = (ArrayType *) DatumGetPointer(arrdatum);
2593 : int nitems;
2594 :
2595 : /*
2596 : * Only fill in the hash functions if the array looks
2597 : * large enough for it to be worth hashing instead of
2598 : * doing a linear search.
2599 : */
2600 1705 : nitems = ArrayGetNItems(ARR_NDIM(arr), ARR_DIMS(arr));
2601 :
2602 1705 : if (nitems >= MIN_ARRAY_SIZE_FOR_HASHED_SAOP)
2603 : {
2604 : /* Looks good. Fill in the hash functions */
2605 82 : saop->hashfuncid = lefthashfunc;
2606 :
2607 : /*
2608 : * Also set the negfuncid. The executor will need
2609 : * that to perform hashtable lookups.
2610 : */
2611 82 : saop->negfuncid = get_opcode(negator);
2612 : }
2613 1705 : return false;
2614 : }
2615 : }
2616 : }
2617 : }
2618 :
2619 4703436 : return expression_tree_walker(node, convert_saop_to_hashed_saop_walker, NULL);
2620 : }
2621 :
2622 :
2623 : /*--------------------
2624 : * estimate_expression_value
2625 : *
2626 : * This function attempts to estimate the value of an expression for
2627 : * planning purposes. It is in essence a more aggressive version of
2628 : * eval_const_expressions(): we will perform constant reductions that are
2629 : * not necessarily 100% safe, but are reasonable for estimation purposes.
2630 : *
2631 : * Currently the extra steps that are taken in this mode are:
2632 : * 1. Substitute values for Params, where a bound Param value has been made
2633 : * available by the caller of planner(), even if the Param isn't marked
2634 : * constant. This effectively means that we plan using the first supplied
2635 : * value of the Param.
2636 : * 2. Fold stable, as well as immutable, functions to constants.
2637 : * 3. Reduce PlaceHolderVar nodes to their contained expressions.
2638 : *--------------------
2639 : */
2640 : Node *
2641 713958 : estimate_expression_value(PlannerInfo *root, Node *node)
2642 : {
2643 : eval_const_expressions_context context;
2644 :
2645 713958 : context.boundParams = root->glob->boundParams; /* bound Params */
2646 : /* we do not need to mark the plan as depending on inlined functions */
2647 713958 : context.root = NULL;
2648 713958 : context.active_fns = NIL; /* nothing being recursively simplified */
2649 713958 : context.case_val = NULL; /* no CASE being examined */
2650 713958 : context.estimate = true; /* unsafe transformations OK */
2651 713958 : return eval_const_expressions_mutator(node, &context);
2652 : }
2653 :
2654 : /*
2655 : * The generic case in eval_const_expressions_mutator is to recurse using
2656 : * expression_tree_mutator, which will copy the given node unchanged but
2657 : * const-simplify its arguments (if any) as far as possible. If the node
2658 : * itself does immutable processing, and each of its arguments were reduced
2659 : * to a Const, we can then reduce it to a Const using evaluate_expr. (Some
2660 : * node types need more complicated logic; for example, a CASE expression
2661 : * might be reducible to a constant even if not all its subtrees are.)
2662 : */
2663 : #define ece_generic_processing(node) \
2664 : expression_tree_mutator((Node *) (node), eval_const_expressions_mutator, \
2665 : context)
2666 :
2667 : /*
2668 : * Check whether all arguments of the given node were reduced to Consts.
2669 : * By going directly to expression_tree_walker, contain_non_const_walker
2670 : * is not applied to the node itself, only to its children.
2671 : */
2672 : #define ece_all_arguments_const(node) \
2673 : (!expression_tree_walker((Node *) (node), contain_non_const_walker, NULL))
2674 :
2675 : /* Generic macro for applying evaluate_expr */
2676 : #define ece_evaluate_expr(node) \
2677 : ((Node *) evaluate_expr((Expr *) (node), \
2678 : exprType((Node *) (node)), \
2679 : exprTypmod((Node *) (node)), \
2680 : exprCollation((Node *) (node))))
2681 :
2682 : /*
2683 : * Recursive guts of eval_const_expressions/estimate_expression_value
2684 : */
2685 : static Node *
2686 7142620 : eval_const_expressions_mutator(Node *node,
2687 : eval_const_expressions_context *context)
2688 : {
2689 :
2690 : /* since this function recurses, it could be driven to stack overflow */
2691 7142620 : check_stack_depth();
2692 :
2693 7142620 : if (node == NULL)
2694 308753 : return NULL;
2695 6833867 : switch (nodeTag(node))
2696 : {
2697 111514 : case T_Param:
2698 : {
2699 111514 : Param *param = (Param *) node;
2700 111514 : ParamListInfo paramLI = context->boundParams;
2701 :
2702 : /* Look to see if we've been given a value for this Param */
2703 111514 : if (param->paramkind == PARAM_EXTERN &&
2704 32770 : paramLI != NULL &&
2705 32770 : param->paramid > 0 &&
2706 32770 : param->paramid <= paramLI->numParams)
2707 : {
2708 : ParamExternData *prm;
2709 : ParamExternData prmdata;
2710 :
2711 : /*
2712 : * Give hook a chance in case parameter is dynamic. Tell
2713 : * it that this fetch is speculative, so it should avoid
2714 : * erroring out if parameter is unavailable.
2715 : */
2716 32770 : if (paramLI->paramFetch != NULL)
2717 4245 : prm = paramLI->paramFetch(paramLI, param->paramid,
2718 : true, &prmdata);
2719 : else
2720 28525 : prm = ¶mLI->params[param->paramid - 1];
2721 :
2722 : /*
2723 : * We don't just check OidIsValid, but insist that the
2724 : * fetched type match the Param, just in case the hook did
2725 : * something unexpected. No need to throw an error here
2726 : * though; leave that for runtime.
2727 : */
2728 32770 : if (OidIsValid(prm->ptype) &&
2729 32770 : prm->ptype == param->paramtype)
2730 : {
2731 : /* OK to substitute parameter value? */
2732 32770 : if (context->estimate ||
2733 32770 : (prm->pflags & PARAM_FLAG_CONST))
2734 : {
2735 : /*
2736 : * Return a Const representing the param value.
2737 : * Must copy pass-by-ref datatypes, since the
2738 : * Param might be in a memory context
2739 : * shorter-lived than our output plan should be.
2740 : */
2741 : int16 typLen;
2742 : bool typByVal;
2743 : Datum pval;
2744 : Const *con;
2745 :
2746 32770 : get_typlenbyval(param->paramtype,
2747 : &typLen, &typByVal);
2748 32770 : if (prm->isnull || typByVal)
2749 20579 : pval = prm->value;
2750 : else
2751 12191 : pval = datumCopy(prm->value, typByVal, typLen);
2752 32770 : con = makeConst(param->paramtype,
2753 : param->paramtypmod,
2754 : param->paramcollid,
2755 : (int) typLen,
2756 : pval,
2757 32770 : prm->isnull,
2758 : typByVal);
2759 32770 : con->location = param->location;
2760 32770 : return (Node *) con;
2761 : }
2762 : }
2763 : }
2764 :
2765 : /*
2766 : * Not replaceable, so just copy the Param (no need to
2767 : * recurse)
2768 : */
2769 78744 : return (Node *) copyObject(param);
2770 : }
2771 3077 : case T_WindowFunc:
2772 : {
2773 3077 : WindowFunc *expr = (WindowFunc *) node;
2774 3077 : Oid funcid = expr->winfnoid;
2775 : List *args;
2776 : Expr *aggfilter;
2777 : HeapTuple func_tuple;
2778 : WindowFunc *newexpr;
2779 :
2780 : /*
2781 : * We can't really simplify a WindowFunc node, but we mustn't
2782 : * just fall through to the default processing, because we
2783 : * have to apply expand_function_arguments to its argument
2784 : * list. That takes care of inserting default arguments and
2785 : * expanding named-argument notation.
2786 : */
2787 3077 : func_tuple = SearchSysCache1(PROCOID, ObjectIdGetDatum(funcid));
2788 3077 : if (!HeapTupleIsValid(func_tuple))
2789 0 : elog(ERROR, "cache lookup failed for function %u", funcid);
2790 :
2791 3077 : args = expand_function_arguments(expr->args,
2792 : false, expr->wintype,
2793 : func_tuple);
2794 :
2795 3077 : ReleaseSysCache(func_tuple);
2796 :
2797 : /* Now, recursively simplify the args (which are a List) */
2798 : args = (List *)
2799 3077 : expression_tree_mutator((Node *) args,
2800 : eval_const_expressions_mutator,
2801 : context);
2802 : /* ... and the filter expression, which isn't */
2803 : aggfilter = (Expr *)
2804 3077 : eval_const_expressions_mutator((Node *) expr->aggfilter,
2805 : context);
2806 :
2807 : /* And build the replacement WindowFunc node */
2808 3077 : newexpr = makeNode(WindowFunc);
2809 3077 : newexpr->winfnoid = expr->winfnoid;
2810 3077 : newexpr->wintype = expr->wintype;
2811 3077 : newexpr->wincollid = expr->wincollid;
2812 3077 : newexpr->inputcollid = expr->inputcollid;
2813 3077 : newexpr->args = args;
2814 3077 : newexpr->aggfilter = aggfilter;
2815 3077 : newexpr->runCondition = expr->runCondition;
2816 3077 : newexpr->winref = expr->winref;
2817 3077 : newexpr->winstar = expr->winstar;
2818 3077 : newexpr->winagg = expr->winagg;
2819 3077 : newexpr->ignore_nulls = expr->ignore_nulls;
2820 3077 : newexpr->location = expr->location;
2821 :
2822 3077 : return (Node *) newexpr;
2823 : }
2824 380690 : case T_FuncExpr:
2825 : {
2826 380690 : FuncExpr *expr = (FuncExpr *) node;
2827 380690 : List *args = expr->args;
2828 : Expr *simple;
2829 : FuncExpr *newexpr;
2830 :
2831 : /*
2832 : * Code for op/func reduction is pretty bulky, so split it out
2833 : * as a separate function. Note: exprTypmod normally returns
2834 : * -1 for a FuncExpr, but not when the node is recognizably a
2835 : * length coercion; we want to preserve the typmod in the
2836 : * eventual Const if so.
2837 : */
2838 380690 : simple = simplify_function(expr->funcid,
2839 : expr->funcresulttype,
2840 : exprTypmod(node),
2841 : expr->funccollid,
2842 : expr->inputcollid,
2843 : &args,
2844 380690 : expr->funcvariadic,
2845 : true,
2846 : true,
2847 : context);
2848 378834 : if (simple) /* successfully simplified it */
2849 110946 : return (Node *) simple;
2850 :
2851 : /*
2852 : * The expression cannot be simplified any further, so build
2853 : * and return a replacement FuncExpr node using the
2854 : * possibly-simplified arguments. Note that we have also
2855 : * converted the argument list to positional notation.
2856 : */
2857 267888 : newexpr = makeNode(FuncExpr);
2858 267888 : newexpr->funcid = expr->funcid;
2859 267888 : newexpr->funcresulttype = expr->funcresulttype;
2860 267888 : newexpr->funcretset = expr->funcretset;
2861 267888 : newexpr->funcvariadic = expr->funcvariadic;
2862 267888 : newexpr->funcformat = expr->funcformat;
2863 267888 : newexpr->funccollid = expr->funccollid;
2864 267888 : newexpr->inputcollid = expr->inputcollid;
2865 267888 : newexpr->args = args;
2866 267888 : newexpr->location = expr->location;
2867 267888 : return (Node *) newexpr;
2868 : }
2869 38101 : case T_Aggref:
2870 38101 : node = ece_generic_processing(node);
2871 38101 : if (context->root != NULL)
2872 38101 : return simplify_aggref((Aggref *) node, context);
2873 0 : return node;
2874 555910 : case T_OpExpr:
2875 : {
2876 555910 : OpExpr *expr = (OpExpr *) node;
2877 555910 : List *args = expr->args;
2878 : Expr *simple;
2879 : OpExpr *newexpr;
2880 :
2881 : /*
2882 : * Need to get OID of underlying function. Okay to scribble
2883 : * on input to this extent.
2884 : */
2885 555910 : set_opfuncid(expr);
2886 :
2887 : /*
2888 : * Code for op/func reduction is pretty bulky, so split it out
2889 : * as a separate function.
2890 : */
2891 555910 : simple = simplify_function(expr->opfuncid,
2892 : expr->opresulttype, -1,
2893 : expr->opcollid,
2894 : expr->inputcollid,
2895 : &args,
2896 : false,
2897 : true,
2898 : true,
2899 : context);
2900 555132 : if (simple) /* successfully simplified it */
2901 20205 : return (Node *) simple;
2902 :
2903 : /*
2904 : * If the operator is boolean equality or inequality, we know
2905 : * how to simplify cases involving one constant and one
2906 : * non-constant argument.
2907 : */
2908 534927 : if (expr->opno == BooleanEqualOperator ||
2909 533303 : expr->opno == BooleanNotEqualOperator)
2910 : {
2911 1764 : simple = (Expr *) simplify_boolean_equality(expr->opno,
2912 : args);
2913 1764 : if (simple) /* successfully simplified it */
2914 1279 : return (Node *) simple;
2915 : }
2916 :
2917 : /*
2918 : * The expression cannot be simplified any further, so build
2919 : * and return a replacement OpExpr node using the
2920 : * possibly-simplified arguments.
2921 : */
2922 533648 : newexpr = makeNode(OpExpr);
2923 533648 : newexpr->opno = expr->opno;
2924 533648 : newexpr->opfuncid = expr->opfuncid;
2925 533648 : newexpr->opresulttype = expr->opresulttype;
2926 533648 : newexpr->opretset = expr->opretset;
2927 533648 : newexpr->opcollid = expr->opcollid;
2928 533648 : newexpr->inputcollid = expr->inputcollid;
2929 533648 : newexpr->args = args;
2930 533648 : newexpr->location = expr->location;
2931 533648 : return (Node *) newexpr;
2932 : }
2933 960 : case T_DistinctExpr:
2934 : {
2935 960 : DistinctExpr *expr = (DistinctExpr *) node;
2936 : List *args;
2937 : ListCell *arg;
2938 960 : bool has_null_input = false;
2939 960 : bool all_null_input = true;
2940 960 : bool has_nonconst_input = false;
2941 960 : bool has_nullable_nonconst = false;
2942 : Expr *simple;
2943 : DistinctExpr *newexpr;
2944 :
2945 : /*
2946 : * Reduce constants in the DistinctExpr's arguments. We know
2947 : * args is either NIL or a List node, so we can call
2948 : * expression_tree_mutator directly rather than recursing to
2949 : * self.
2950 : */
2951 960 : args = (List *) expression_tree_mutator((Node *) expr->args,
2952 : eval_const_expressions_mutator,
2953 : context);
2954 :
2955 : /*
2956 : * We must do our own check for NULLs because DistinctExpr has
2957 : * different results for NULL input than the underlying
2958 : * operator does. We also check if any non-constant input is
2959 : * potentially nullable.
2960 : */
2961 2880 : foreach(arg, args)
2962 : {
2963 1920 : if (IsA(lfirst(arg), Const))
2964 : {
2965 335 : has_null_input |= ((Const *) lfirst(arg))->constisnull;
2966 335 : all_null_input &= ((Const *) lfirst(arg))->constisnull;
2967 : }
2968 : else
2969 : {
2970 1585 : has_nonconst_input = true;
2971 1585 : all_null_input = false;
2972 :
2973 1585 : if (!has_nullable_nonconst &&
2974 940 : !expr_is_nonnullable(context->root,
2975 940 : (Expr *) lfirst(arg),
2976 : NOTNULL_SOURCE_HASHTABLE))
2977 855 : has_nullable_nonconst = true;
2978 : }
2979 : }
2980 :
2981 960 : if (!has_nonconst_input)
2982 : {
2983 : /*
2984 : * All inputs are constants. We can optimize this out
2985 : * completely.
2986 : */
2987 :
2988 : /* all nulls? then not distinct */
2989 45 : if (all_null_input)
2990 10 : return makeBoolConst(false, false);
2991 :
2992 : /* one null? then distinct */
2993 35 : if (has_null_input)
2994 15 : return makeBoolConst(true, false);
2995 :
2996 : /* otherwise try to evaluate the '=' operator */
2997 : /* (NOT okay to try to inline it, though!) */
2998 :
2999 : /*
3000 : * Need to get OID of underlying function. Okay to
3001 : * scribble on input to this extent.
3002 : */
3003 20 : set_opfuncid((OpExpr *) expr); /* rely on struct
3004 : * equivalence */
3005 :
3006 : /*
3007 : * Code for op/func reduction is pretty bulky, so split it
3008 : * out as a separate function.
3009 : */
3010 20 : simple = simplify_function(expr->opfuncid,
3011 : expr->opresulttype, -1,
3012 : expr->opcollid,
3013 : expr->inputcollid,
3014 : &args,
3015 : false,
3016 : false,
3017 : false,
3018 : context);
3019 20 : if (simple) /* successfully simplified it */
3020 : {
3021 : /*
3022 : * Since the underlying operator is "=", must negate
3023 : * its result
3024 : */
3025 20 : Const *csimple = castNode(Const, simple);
3026 :
3027 20 : csimple->constvalue =
3028 20 : BoolGetDatum(!DatumGetBool(csimple->constvalue));
3029 20 : return (Node *) csimple;
3030 : }
3031 : }
3032 915 : else if (!has_nullable_nonconst)
3033 : {
3034 : /*
3035 : * There are non-constant inputs, but since all of them
3036 : * are proven non-nullable, "IS DISTINCT FROM" semantics
3037 : * are much simpler.
3038 : */
3039 :
3040 : OpExpr *eqexpr;
3041 :
3042 : /*
3043 : * If one input is an explicit NULL constant, and the
3044 : * other is a non-nullable expression, the result is
3045 : * always TRUE.
3046 : */
3047 60 : if (has_null_input)
3048 20 : return makeBoolConst(true, false);
3049 :
3050 : /*
3051 : * Otherwise, both inputs are known non-nullable. In this
3052 : * case, "IS DISTINCT FROM" is equivalent to the standard
3053 : * inequality operator (usually "<>"). We convert this to
3054 : * an OpExpr, which is a more efficient representation for
3055 : * the planner. It can enable the use of partial indexes
3056 : * and constraint exclusion. Furthermore, if the clause
3057 : * is negated (ie, "IS NOT DISTINCT FROM"), the resulting
3058 : * "=" operator can allow the planner to use index scans,
3059 : * merge joins, hash joins, and EC-based qual deductions.
3060 : */
3061 40 : eqexpr = makeNode(OpExpr);
3062 40 : eqexpr->opno = expr->opno;
3063 40 : eqexpr->opfuncid = expr->opfuncid;
3064 40 : eqexpr->opresulttype = BOOLOID;
3065 40 : eqexpr->opretset = expr->opretset;
3066 40 : eqexpr->opcollid = expr->opcollid;
3067 40 : eqexpr->inputcollid = expr->inputcollid;
3068 40 : eqexpr->args = args;
3069 40 : eqexpr->location = expr->location;
3070 :
3071 40 : return eval_const_expressions_mutator(negate_clause((Node *) eqexpr),
3072 : context);
3073 : }
3074 855 : else if (has_null_input)
3075 : {
3076 : /*
3077 : * One input is a nullable non-constant expression, and
3078 : * the other is an explicit NULL constant. We can
3079 : * transform this to a NullTest with !argisrow, which is
3080 : * much more amenable to optimization.
3081 : */
3082 :
3083 40 : NullTest *nt = makeNode(NullTest);
3084 :
3085 80 : nt->arg = (Expr *) (IsA(linitial(args), Const) ?
3086 40 : lsecond(args) : linitial(args));
3087 40 : nt->nulltesttype = IS_NOT_NULL;
3088 :
3089 : /*
3090 : * argisrow = false is correct whether or not arg is
3091 : * composite
3092 : */
3093 40 : nt->argisrow = false;
3094 40 : nt->location = expr->location;
3095 :
3096 40 : return eval_const_expressions_mutator((Node *) nt, context);
3097 : }
3098 :
3099 : /*
3100 : * The expression cannot be simplified any further, so build
3101 : * and return a replacement DistinctExpr node using the
3102 : * possibly-simplified arguments.
3103 : */
3104 815 : newexpr = makeNode(DistinctExpr);
3105 815 : newexpr->opno = expr->opno;
3106 815 : newexpr->opfuncid = expr->opfuncid;
3107 815 : newexpr->opresulttype = expr->opresulttype;
3108 815 : newexpr->opretset = expr->opretset;
3109 815 : newexpr->opcollid = expr->opcollid;
3110 815 : newexpr->inputcollid = expr->inputcollid;
3111 815 : newexpr->args = args;
3112 815 : newexpr->location = expr->location;
3113 815 : return (Node *) newexpr;
3114 : }
3115 904 : case T_NullIfExpr:
3116 : {
3117 : NullIfExpr *expr;
3118 : ListCell *arg;
3119 904 : bool has_nonconst_input = false;
3120 :
3121 : /* Copy the node and const-simplify its arguments */
3122 904 : expr = (NullIfExpr *) ece_generic_processing(node);
3123 :
3124 : /* If either argument is NULL they can't be equal */
3125 2707 : foreach(arg, expr->args)
3126 : {
3127 1808 : if (!IsA(lfirst(arg), Const))
3128 878 : has_nonconst_input = true;
3129 930 : else if (((Const *) lfirst(arg))->constisnull)
3130 5 : return (Node *) linitial(expr->args);
3131 : }
3132 :
3133 : /*
3134 : * Need to get OID of underlying function before checking if
3135 : * the function is OK to evaluate.
3136 : */
3137 899 : set_opfuncid((OpExpr *) expr);
3138 :
3139 930 : if (!has_nonconst_input &&
3140 31 : ece_function_is_safe(expr->opfuncid, context))
3141 31 : return ece_evaluate_expr(expr);
3142 :
3143 868 : return (Node *) expr;
3144 : }
3145 29353 : case T_ScalarArrayOpExpr:
3146 : {
3147 : ScalarArrayOpExpr *saop;
3148 :
3149 : /* Copy the node and const-simplify its arguments */
3150 29353 : saop = (ScalarArrayOpExpr *) ece_generic_processing(node);
3151 :
3152 : /* Make sure we know underlying function */
3153 29353 : set_sa_opfuncid(saop);
3154 :
3155 : /*
3156 : * If all arguments are Consts, and it's a safe function, we
3157 : * can fold to a constant
3158 : */
3159 29622 : if (ece_all_arguments_const(saop) &&
3160 269 : ece_function_is_safe(saop->opfuncid, context))
3161 269 : return ece_evaluate_expr(saop);
3162 29084 : return (Node *) saop;
3163 : }
3164 146871 : case T_BoolExpr:
3165 : {
3166 146871 : BoolExpr *expr = (BoolExpr *) node;
3167 :
3168 146871 : switch (expr->boolop)
3169 : {
3170 15328 : case OR_EXPR:
3171 : {
3172 : List *newargs;
3173 15328 : bool haveNull = false;
3174 15328 : bool forceTrue = false;
3175 :
3176 15328 : newargs = simplify_or_arguments(expr->args,
3177 : context,
3178 : &haveNull,
3179 : &forceTrue);
3180 15328 : if (forceTrue)
3181 106 : return makeBoolConst(true, false);
3182 15222 : if (haveNull)
3183 3802 : newargs = lappend(newargs,
3184 3802 : makeBoolConst(false, true));
3185 : /* If all the inputs are FALSE, result is FALSE */
3186 15222 : if (newargs == NIL)
3187 28 : return makeBoolConst(false, false);
3188 :
3189 : /*
3190 : * If only one nonconst-or-NULL input, it's the
3191 : * result
3192 : */
3193 15194 : if (list_length(newargs) == 1)
3194 87 : return (Node *) linitial(newargs);
3195 : /* Else we still need an OR node */
3196 15107 : return (Node *) make_orclause(newargs);
3197 : }
3198 116558 : case AND_EXPR:
3199 : {
3200 : List *newargs;
3201 116558 : bool haveNull = false;
3202 116558 : bool forceFalse = false;
3203 :
3204 116558 : newargs = simplify_and_arguments(expr->args,
3205 : context,
3206 : &haveNull,
3207 : &forceFalse);
3208 116558 : if (forceFalse)
3209 655 : return makeBoolConst(false, false);
3210 115903 : if (haveNull)
3211 25 : newargs = lappend(newargs,
3212 25 : makeBoolConst(false, true));
3213 : /* If all the inputs are TRUE, result is TRUE */
3214 115903 : if (newargs == NIL)
3215 186 : return makeBoolConst(true, false);
3216 :
3217 : /*
3218 : * If only one nonconst-or-NULL input, it's the
3219 : * result
3220 : */
3221 115717 : if (list_length(newargs) == 1)
3222 177 : return (Node *) linitial(newargs);
3223 : /* Else we still need an AND node */
3224 115540 : return (Node *) make_andclause(newargs);
3225 : }
3226 14985 : case NOT_EXPR:
3227 : {
3228 : Node *arg;
3229 :
3230 : Assert(list_length(expr->args) == 1);
3231 14985 : arg = eval_const_expressions_mutator(linitial(expr->args),
3232 : context);
3233 :
3234 : /*
3235 : * Use negate_clause() to see if we can simplify
3236 : * away the NOT.
3237 : */
3238 14985 : return negate_clause(arg);
3239 : }
3240 0 : default:
3241 0 : elog(ERROR, "unrecognized boolop: %d",
3242 : (int) expr->boolop);
3243 : break;
3244 : }
3245 : break;
3246 : }
3247 637 : case T_JsonValueExpr:
3248 : {
3249 637 : JsonValueExpr *jve = (JsonValueExpr *) node;
3250 637 : Node *raw_expr = (Node *) jve->raw_expr;
3251 637 : Node *formatted_expr = (Node *) jve->formatted_expr;
3252 :
3253 : /*
3254 : * If we can fold formatted_expr to a constant, we can elide
3255 : * the JsonValueExpr altogether. Otherwise we must process
3256 : * raw_expr too. But JsonFormat is a flat node and requires
3257 : * no simplification, only copying.
3258 : */
3259 637 : formatted_expr = eval_const_expressions_mutator(formatted_expr,
3260 : context);
3261 637 : if (formatted_expr && IsA(formatted_expr, Const))
3262 443 : return formatted_expr;
3263 :
3264 194 : raw_expr = eval_const_expressions_mutator(raw_expr, context);
3265 :
3266 194 : return (Node *) makeJsonValueExpr((Expr *) raw_expr,
3267 : (Expr *) formatted_expr,
3268 194 : copyObject(jve->format));
3269 : }
3270 1403 : case T_JsonConstructorExpr:
3271 : {
3272 1403 : JsonConstructorExpr *jce = (JsonConstructorExpr *) node;
3273 :
3274 : /*
3275 : * JSCTOR_JSON_ARRAY_QUERY carries a pre-built executable form
3276 : * in its func field (a COALESCE-wrapped JSON_ARRAYAGG
3277 : * subquery, constructed during parse analysis). Replace the
3278 : * node with that expression and continue simplifying.
3279 : */
3280 1403 : if (jce->type == JSCTOR_JSON_ARRAY_QUERY)
3281 60 : return eval_const_expressions_mutator((Node *) jce->func,
3282 : context);
3283 : }
3284 1343 : break;
3285 485 : case T_SubPlan:
3286 : case T_AlternativeSubPlan:
3287 :
3288 : /*
3289 : * Return a SubPlan unchanged --- too late to do anything with it.
3290 : *
3291 : * XXX should we ereport() here instead? Probably this routine
3292 : * should never be invoked after SubPlan creation.
3293 : */
3294 485 : return node;
3295 130004 : case T_RelabelType:
3296 : {
3297 130004 : RelabelType *relabel = (RelabelType *) node;
3298 : Node *arg;
3299 :
3300 : /* Simplify the input ... */
3301 130004 : arg = eval_const_expressions_mutator((Node *) relabel->arg,
3302 : context);
3303 : /* ... and attach a new RelabelType node, if needed */
3304 130000 : return applyRelabelType(arg,
3305 : relabel->resulttype,
3306 : relabel->resulttypmod,
3307 : relabel->resultcollid,
3308 : relabel->relabelformat,
3309 : relabel->location,
3310 : true);
3311 : }
3312 24885 : case T_CoerceViaIO:
3313 : {
3314 24885 : CoerceViaIO *expr = (CoerceViaIO *) node;
3315 : List *args;
3316 : Oid outfunc;
3317 : bool outtypisvarlena;
3318 : Oid infunc;
3319 : Oid intypioparam;
3320 : Expr *simple;
3321 : CoerceViaIO *newexpr;
3322 :
3323 : /* Make a List so we can use simplify_function */
3324 24885 : args = list_make1(expr->arg);
3325 :
3326 : /*
3327 : * CoerceViaIO represents calling the source type's output
3328 : * function then the result type's input function. So, try to
3329 : * simplify it as though it were a stack of two such function
3330 : * calls. First we need to know what the functions are.
3331 : *
3332 : * Note that the coercion functions are assumed not to care
3333 : * about input collation, so we just pass InvalidOid for that.
3334 : */
3335 24885 : getTypeOutputInfo(exprType((Node *) expr->arg),
3336 : &outfunc, &outtypisvarlena);
3337 24885 : getTypeInputInfo(expr->resulttype,
3338 : &infunc, &intypioparam);
3339 :
3340 24885 : simple = simplify_function(outfunc,
3341 : CSTRINGOID, -1,
3342 : InvalidOid,
3343 : InvalidOid,
3344 : &args,
3345 : false,
3346 : true,
3347 : true,
3348 : context);
3349 24885 : if (simple) /* successfully simplified output fn */
3350 : {
3351 : /*
3352 : * Input functions may want 1 to 3 arguments. We always
3353 : * supply all three, trusting that nothing downstream will
3354 : * complain.
3355 : */
3356 1901 : args = list_make3(simple,
3357 : makeConst(OIDOID,
3358 : -1,
3359 : InvalidOid,
3360 : sizeof(Oid),
3361 : ObjectIdGetDatum(intypioparam),
3362 : false,
3363 : true),
3364 : makeConst(INT4OID,
3365 : -1,
3366 : InvalidOid,
3367 : sizeof(int32),
3368 : Int32GetDatum(-1),
3369 : false,
3370 : true));
3371 :
3372 1901 : simple = simplify_function(infunc,
3373 : expr->resulttype, -1,
3374 : expr->resultcollid,
3375 : InvalidOid,
3376 : &args,
3377 : false,
3378 : false,
3379 : true,
3380 : context);
3381 1828 : if (simple) /* successfully simplified input fn */
3382 1765 : return (Node *) simple;
3383 : }
3384 :
3385 : /*
3386 : * The expression cannot be simplified any further, so build
3387 : * and return a replacement CoerceViaIO node using the
3388 : * possibly-simplified argument.
3389 : */
3390 23047 : newexpr = makeNode(CoerceViaIO);
3391 23047 : newexpr->arg = (Expr *) linitial(args);
3392 23047 : newexpr->resulttype = expr->resulttype;
3393 23047 : newexpr->resultcollid = expr->resultcollid;
3394 23047 : newexpr->coerceformat = expr->coerceformat;
3395 23047 : newexpr->location = expr->location;
3396 23047 : return (Node *) newexpr;
3397 : }
3398 8169 : case T_ArrayCoerceExpr:
3399 : {
3400 8169 : ArrayCoerceExpr *ac = makeNode(ArrayCoerceExpr);
3401 : Node *save_case_val;
3402 :
3403 : /*
3404 : * Copy the node and const-simplify its arguments. We can't
3405 : * use ece_generic_processing() here because we need to mess
3406 : * with case_val only while processing the elemexpr.
3407 : */
3408 8169 : memcpy(ac, node, sizeof(ArrayCoerceExpr));
3409 8169 : ac->arg = (Expr *)
3410 8169 : eval_const_expressions_mutator((Node *) ac->arg,
3411 : context);
3412 :
3413 : /*
3414 : * Set up for the CaseTestExpr node contained in the elemexpr.
3415 : * We must prevent it from absorbing any outer CASE value.
3416 : */
3417 8169 : save_case_val = context->case_val;
3418 8169 : context->case_val = NULL;
3419 :
3420 8169 : ac->elemexpr = (Expr *)
3421 8169 : eval_const_expressions_mutator((Node *) ac->elemexpr,
3422 : context);
3423 :
3424 8169 : context->case_val = save_case_val;
3425 :
3426 : /*
3427 : * If constant argument and the per-element expression is
3428 : * immutable, we can simplify the whole thing to a constant.
3429 : * Exception: although contain_mutable_functions considers
3430 : * CoerceToDomain immutable for historical reasons, let's not
3431 : * do so here; this ensures coercion to an array-over-domain
3432 : * does not apply the domain's constraints until runtime.
3433 : */
3434 8169 : if (ac->arg && IsA(ac->arg, Const) &&
3435 884 : ac->elemexpr && !IsA(ac->elemexpr, CoerceToDomain) &&
3436 864 : !contain_mutable_functions((Node *) ac->elemexpr))
3437 864 : return ece_evaluate_expr(ac);
3438 :
3439 7305 : return (Node *) ac;
3440 : }
3441 8238 : case T_CollateExpr:
3442 : {
3443 : /*
3444 : * We replace CollateExpr with RelabelType, so as to improve
3445 : * uniformity of expression representation and thus simplify
3446 : * comparison of expressions. Hence this looks very nearly
3447 : * the same as the RelabelType case, and we can apply the same
3448 : * optimizations to avoid unnecessary RelabelTypes.
3449 : */
3450 8238 : CollateExpr *collate = (CollateExpr *) node;
3451 : Node *arg;
3452 :
3453 : /* Simplify the input ... */
3454 8238 : arg = eval_const_expressions_mutator((Node *) collate->arg,
3455 : context);
3456 : /* ... and attach a new RelabelType node, if needed */
3457 8238 : return applyRelabelType(arg,
3458 : exprType(arg),
3459 : exprTypmod(arg),
3460 : collate->collOid,
3461 : COERCE_IMPLICIT_CAST,
3462 : collate->location,
3463 : true);
3464 : }
3465 28163 : case T_CaseExpr:
3466 : {
3467 : /*----------
3468 : * CASE expressions can be simplified if there are constant
3469 : * condition clauses:
3470 : * FALSE (or NULL): drop the alternative
3471 : * TRUE: drop all remaining alternatives
3472 : * If the first non-FALSE alternative is a constant TRUE,
3473 : * we can simplify the entire CASE to that alternative's
3474 : * expression. If there are no non-FALSE alternatives,
3475 : * we simplify the entire CASE to the default result (ELSE).
3476 : *
3477 : * If we have a simple-form CASE with constant test
3478 : * expression, we substitute the constant value for contained
3479 : * CaseTestExpr placeholder nodes, so that we have the
3480 : * opportunity to reduce constant test conditions. For
3481 : * example this allows
3482 : * CASE 0 WHEN 0 THEN 1 ELSE 1/0 END
3483 : * to reduce to 1 rather than drawing a divide-by-0 error.
3484 : * Note that when the test expression is constant, we don't
3485 : * have to include it in the resulting CASE; for example
3486 : * CASE 0 WHEN x THEN y ELSE z END
3487 : * is transformed by the parser to
3488 : * CASE 0 WHEN CaseTestExpr = x THEN y ELSE z END
3489 : * which we can simplify to
3490 : * CASE WHEN 0 = x THEN y ELSE z END
3491 : * It is not necessary for the executor to evaluate the "arg"
3492 : * expression when executing the CASE, since any contained
3493 : * CaseTestExprs that might have referred to it will have been
3494 : * replaced by the constant.
3495 : *----------
3496 : */
3497 28163 : CaseExpr *caseexpr = (CaseExpr *) node;
3498 : CaseExpr *newcase;
3499 : Node *save_case_val;
3500 : Node *newarg;
3501 : List *newargs;
3502 : bool const_true_cond;
3503 28163 : Node *defresult = NULL;
3504 : ListCell *arg;
3505 :
3506 : /* Simplify the test expression, if any */
3507 28163 : newarg = eval_const_expressions_mutator((Node *) caseexpr->arg,
3508 : context);
3509 :
3510 : /* Set up for contained CaseTestExpr nodes */
3511 28163 : save_case_val = context->case_val;
3512 28163 : if (newarg && IsA(newarg, Const))
3513 : {
3514 65 : context->case_val = newarg;
3515 65 : newarg = NULL; /* not needed anymore, see above */
3516 : }
3517 : else
3518 28098 : context->case_val = NULL;
3519 :
3520 : /* Simplify the WHEN clauses */
3521 28163 : newargs = NIL;
3522 28163 : const_true_cond = false;
3523 86304 : foreach(arg, caseexpr->args)
3524 : {
3525 58562 : CaseWhen *oldcasewhen = lfirst_node(CaseWhen, arg);
3526 : Node *casecond;
3527 : Node *caseresult;
3528 :
3529 : /* Simplify this alternative's test condition */
3530 58562 : casecond = eval_const_expressions_mutator((Node *) oldcasewhen->expr,
3531 : context);
3532 :
3533 : /*
3534 : * If the test condition is constant FALSE (or NULL), then
3535 : * drop this WHEN clause completely, without processing
3536 : * the result.
3537 : */
3538 58562 : if (casecond && IsA(casecond, Const))
3539 : {
3540 880 : Const *const_input = (Const *) casecond;
3541 :
3542 880 : if (const_input->constisnull ||
3543 880 : !DatumGetBool(const_input->constvalue))
3544 463 : continue; /* drop alternative with FALSE cond */
3545 : /* Else it's constant TRUE */
3546 417 : const_true_cond = true;
3547 : }
3548 :
3549 : /* Simplify this alternative's result value */
3550 58099 : caseresult = eval_const_expressions_mutator((Node *) oldcasewhen->result,
3551 : context);
3552 :
3553 : /* If non-constant test condition, emit a new WHEN node */
3554 58095 : if (!const_true_cond)
3555 57678 : {
3556 57678 : CaseWhen *newcasewhen = makeNode(CaseWhen);
3557 :
3558 57678 : newcasewhen->expr = (Expr *) casecond;
3559 57678 : newcasewhen->result = (Expr *) caseresult;
3560 57678 : newcasewhen->location = oldcasewhen->location;
3561 57678 : newargs = lappend(newargs, newcasewhen);
3562 57678 : continue;
3563 : }
3564 :
3565 : /*
3566 : * Found a TRUE condition, so none of the remaining
3567 : * alternatives can be reached. We treat the result as
3568 : * the default result.
3569 : */
3570 417 : defresult = caseresult;
3571 417 : break;
3572 : }
3573 :
3574 : /* Simplify the default result, unless we replaced it above */
3575 28159 : if (!const_true_cond)
3576 27742 : defresult = eval_const_expressions_mutator((Node *) caseexpr->defresult,
3577 : context);
3578 :
3579 28159 : context->case_val = save_case_val;
3580 :
3581 : /*
3582 : * If no non-FALSE alternatives, CASE reduces to the default
3583 : * result
3584 : */
3585 28159 : if (newargs == NIL)
3586 633 : return defresult;
3587 : /* Otherwise we need a new CASE node */
3588 27526 : newcase = makeNode(CaseExpr);
3589 27526 : newcase->casetype = caseexpr->casetype;
3590 27526 : newcase->casecollid = caseexpr->casecollid;
3591 27526 : newcase->arg = (Expr *) newarg;
3592 27526 : newcase->args = newargs;
3593 27526 : newcase->defresult = (Expr *) defresult;
3594 27526 : newcase->location = caseexpr->location;
3595 27526 : return (Node *) newcase;
3596 : }
3597 28187 : case T_CaseTestExpr:
3598 : {
3599 : /*
3600 : * If we know a constant test value for the current CASE
3601 : * construct, substitute it for the placeholder. Else just
3602 : * return the placeholder as-is.
3603 : */
3604 28187 : if (context->case_val)
3605 119 : return copyObject(context->case_val);
3606 : else
3607 28068 : return copyObject(node);
3608 : }
3609 48542 : case T_SubscriptingRef:
3610 : case T_ArrayExpr:
3611 : case T_RowExpr:
3612 : case T_MinMaxExpr:
3613 : {
3614 : /*
3615 : * Generic handling for node types whose own processing is
3616 : * known to be immutable, and for which we need no smarts
3617 : * beyond "simplify if all inputs are constants".
3618 : *
3619 : * Treating SubscriptingRef this way assumes that subscripting
3620 : * fetch and assignment are both immutable. This constrains
3621 : * type-specific subscripting implementations; maybe we should
3622 : * relax it someday.
3623 : *
3624 : * Treating MinMaxExpr this way amounts to assuming that the
3625 : * btree comparison function it calls is immutable; see the
3626 : * reasoning in contain_mutable_functions_walker.
3627 : */
3628 :
3629 : /* Copy the node and const-simplify its arguments */
3630 48542 : node = ece_generic_processing(node);
3631 : /* If all arguments are Consts, we can fold to a constant */
3632 48542 : if (ece_all_arguments_const(node))
3633 23318 : return ece_evaluate_expr(node);
3634 25224 : return node;
3635 : }
3636 2456 : case T_CoalesceExpr:
3637 : {
3638 2456 : CoalesceExpr *coalesceexpr = (CoalesceExpr *) node;
3639 : CoalesceExpr *newcoalesce;
3640 : List *newargs;
3641 : ListCell *arg;
3642 :
3643 2456 : newargs = NIL;
3644 5856 : foreach(arg, coalesceexpr->args)
3645 : {
3646 : Node *e;
3647 :
3648 4820 : e = eval_const_expressions_mutator((Node *) lfirst(arg),
3649 : context);
3650 :
3651 : /*
3652 : * We can remove null constants from the list. For a
3653 : * nonnullable expression, if it has not been preceded by
3654 : * any non-null-constant expressions then it is the
3655 : * result. Otherwise, it's the next argument, but we can
3656 : * drop following arguments since they will never be
3657 : * reached.
3658 : */
3659 4820 : if (IsA(e, Const))
3660 : {
3661 1386 : if (((Const *) e)->constisnull)
3662 46 : continue; /* drop null constant */
3663 1340 : if (newargs == NIL)
3664 133 : return e; /* first expr */
3665 1257 : newargs = lappend(newargs, e);
3666 1257 : break;
3667 : }
3668 3434 : if (expr_is_nonnullable(context->root, (Expr *) e,
3669 : NOTNULL_SOURCE_HASHTABLE))
3670 : {
3671 80 : if (newargs == NIL)
3672 50 : return e; /* first expr */
3673 30 : newargs = lappend(newargs, e);
3674 30 : break;
3675 : }
3676 :
3677 3354 : newargs = lappend(newargs, e);
3678 : }
3679 :
3680 : /*
3681 : * If all the arguments were constant null, the result is just
3682 : * null
3683 : */
3684 2323 : if (newargs == NIL)
3685 0 : return (Node *) makeNullConst(coalesceexpr->coalescetype,
3686 : -1,
3687 : coalesceexpr->coalescecollid);
3688 :
3689 : /*
3690 : * If there's exactly one surviving argument, we no longer
3691 : * need COALESCE at all: the result is that argument
3692 : */
3693 2323 : if (list_length(newargs) == 1)
3694 15 : return (Node *) linitial(newargs);
3695 :
3696 2308 : newcoalesce = makeNode(CoalesceExpr);
3697 2308 : newcoalesce->coalescetype = coalesceexpr->coalescetype;
3698 2308 : newcoalesce->coalescecollid = coalesceexpr->coalescecollid;
3699 2308 : newcoalesce->args = newargs;
3700 2308 : newcoalesce->location = coalesceexpr->location;
3701 2308 : return (Node *) newcoalesce;
3702 : }
3703 4107 : case T_SQLValueFunction:
3704 : {
3705 : /*
3706 : * All variants of SQLValueFunction are stable, so if we are
3707 : * estimating the expression's value, we should evaluate the
3708 : * current function value. Otherwise just copy.
3709 : */
3710 4107 : SQLValueFunction *svf = (SQLValueFunction *) node;
3711 :
3712 4107 : if (context->estimate)
3713 742 : return (Node *) evaluate_expr((Expr *) svf,
3714 : svf->type,
3715 : svf->typmod,
3716 : InvalidOid);
3717 : else
3718 3365 : return copyObject((Node *) svf);
3719 : }
3720 24843 : case T_FieldSelect:
3721 : {
3722 : /*
3723 : * We can optimize field selection from a whole-row Var into a
3724 : * simple Var. (This case won't be generated directly by the
3725 : * parser, because ParseComplexProjection short-circuits it.
3726 : * But it can arise while simplifying functions.) Also, we
3727 : * can optimize field selection from a RowExpr construct, or
3728 : * of course from a constant.
3729 : *
3730 : * However, replacing a whole-row Var in this way has a
3731 : * pitfall: if we've already built the rel targetlist for the
3732 : * source relation, then the whole-row Var is scheduled to be
3733 : * produced by the relation scan, but the simple Var probably
3734 : * isn't, which will lead to a failure in setrefs.c. This is
3735 : * not a problem when handling simple single-level queries, in
3736 : * which expression simplification always happens first. It
3737 : * is a risk for lateral references from subqueries, though.
3738 : * To avoid such failures, don't optimize uplevel references.
3739 : *
3740 : * We must also check that the declared type of the field is
3741 : * still the same as when the FieldSelect was created --- this
3742 : * can change if someone did ALTER COLUMN TYPE on the rowtype.
3743 : * If it isn't, we skip the optimization; the case will
3744 : * probably fail at runtime, but that's not our problem here.
3745 : */
3746 24843 : FieldSelect *fselect = (FieldSelect *) node;
3747 : FieldSelect *newfselect;
3748 : Node *arg;
3749 :
3750 24843 : arg = eval_const_expressions_mutator((Node *) fselect->arg,
3751 : context);
3752 24843 : if (arg && IsA(arg, Var) &&
3753 21924 : ((Var *) arg)->varattno == InvalidAttrNumber &&
3754 75 : ((Var *) arg)->varlevelsup == 0)
3755 : {
3756 65 : if (rowtype_field_matches(((Var *) arg)->vartype,
3757 65 : fselect->fieldnum,
3758 : fselect->resulttype,
3759 : fselect->resulttypmod,
3760 : fselect->resultcollid))
3761 : {
3762 : Var *newvar;
3763 :
3764 65 : newvar = makeVar(((Var *) arg)->varno,
3765 65 : fselect->fieldnum,
3766 : fselect->resulttype,
3767 : fselect->resulttypmod,
3768 : fselect->resultcollid,
3769 : ((Var *) arg)->varlevelsup);
3770 : /* New Var has same OLD/NEW returning as old one */
3771 65 : newvar->varreturningtype = ((Var *) arg)->varreturningtype;
3772 : /* New Var is nullable by same rels as the old one */
3773 65 : newvar->varnullingrels = ((Var *) arg)->varnullingrels;
3774 65 : return (Node *) newvar;
3775 : }
3776 : }
3777 24778 : if (arg && IsA(arg, RowExpr))
3778 : {
3779 20 : RowExpr *rowexpr = (RowExpr *) arg;
3780 :
3781 40 : if (fselect->fieldnum > 0 &&
3782 20 : fselect->fieldnum <= list_length(rowexpr->args))
3783 : {
3784 20 : Node *fld = (Node *) list_nth(rowexpr->args,
3785 20 : fselect->fieldnum - 1);
3786 :
3787 20 : if (rowtype_field_matches(rowexpr->row_typeid,
3788 20 : fselect->fieldnum,
3789 : fselect->resulttype,
3790 : fselect->resulttypmod,
3791 20 : fselect->resultcollid) &&
3792 40 : fselect->resulttype == exprType(fld) &&
3793 40 : fselect->resulttypmod == exprTypmod(fld) &&
3794 20 : fselect->resultcollid == exprCollation(fld))
3795 20 : return fld;
3796 : }
3797 : }
3798 24758 : newfselect = makeNode(FieldSelect);
3799 24758 : newfselect->arg = (Expr *) arg;
3800 24758 : newfselect->fieldnum = fselect->fieldnum;
3801 24758 : newfselect->resulttype = fselect->resulttype;
3802 24758 : newfselect->resulttypmod = fselect->resulttypmod;
3803 24758 : newfselect->resultcollid = fselect->resultcollid;
3804 24758 : if (arg && IsA(arg, Const))
3805 : {
3806 509 : Const *con = (Const *) arg;
3807 :
3808 509 : if (rowtype_field_matches(con->consttype,
3809 509 : newfselect->fieldnum,
3810 : newfselect->resulttype,
3811 : newfselect->resulttypmod,
3812 : newfselect->resultcollid))
3813 509 : return ece_evaluate_expr(newfselect);
3814 : }
3815 24249 : return (Node *) newfselect;
3816 : }
3817 28132 : case T_NullTest:
3818 : {
3819 28132 : NullTest *ntest = (NullTest *) node;
3820 : NullTest *newntest;
3821 : Node *arg;
3822 :
3823 28132 : arg = eval_const_expressions_mutator((Node *) ntest->arg,
3824 : context);
3825 28131 : if (ntest->argisrow && arg && IsA(arg, RowExpr))
3826 : {
3827 : /*
3828 : * We break ROW(...) IS [NOT] NULL into separate tests on
3829 : * its component fields. This form is usually more
3830 : * efficient to evaluate, as well as being more amenable
3831 : * to optimization.
3832 : */
3833 37 : RowExpr *rarg = (RowExpr *) arg;
3834 37 : List *newargs = NIL;
3835 : ListCell *l;
3836 :
3837 136 : foreach(l, rarg->args)
3838 : {
3839 99 : Node *relem = (Node *) lfirst(l);
3840 :
3841 : /*
3842 : * A constant field refutes the whole NullTest if it's
3843 : * of the wrong nullness; else we can discard it.
3844 : */
3845 99 : if (relem && IsA(relem, Const))
3846 0 : {
3847 0 : Const *carg = (Const *) relem;
3848 :
3849 0 : if (carg->constisnull ?
3850 0 : (ntest->nulltesttype == IS_NOT_NULL) :
3851 0 : (ntest->nulltesttype == IS_NULL))
3852 0 : return makeBoolConst(false, false);
3853 0 : continue;
3854 : }
3855 :
3856 : /*
3857 : * A proven non-nullable field refutes the whole
3858 : * NullTest if the test is IS NULL; else we can
3859 : * discard it.
3860 : */
3861 198 : if (relem &&
3862 99 : expr_is_nonnullable(context->root, (Expr *) relem,
3863 : NOTNULL_SOURCE_HASHTABLE))
3864 : {
3865 0 : if (ntest->nulltesttype == IS_NULL)
3866 0 : return makeBoolConst(false, false);
3867 0 : continue;
3868 : }
3869 :
3870 : /*
3871 : * Else, make a scalar (argisrow == false) NullTest
3872 : * for this field. Scalar semantics are required
3873 : * because IS [NOT] NULL doesn't recurse; see comments
3874 : * in ExecEvalRowNullInt().
3875 : */
3876 99 : newntest = makeNode(NullTest);
3877 99 : newntest->arg = (Expr *) relem;
3878 99 : newntest->nulltesttype = ntest->nulltesttype;
3879 99 : newntest->argisrow = false;
3880 99 : newntest->location = ntest->location;
3881 99 : newargs = lappend(newargs, newntest);
3882 : }
3883 : /* If all the inputs were constants, result is TRUE */
3884 37 : if (newargs == NIL)
3885 0 : return makeBoolConst(true, false);
3886 : /* If only one nonconst input, it's the result */
3887 37 : if (list_length(newargs) == 1)
3888 0 : return (Node *) linitial(newargs);
3889 : /* Else we need an AND node */
3890 37 : return (Node *) make_andclause(newargs);
3891 : }
3892 28094 : if (!ntest->argisrow && arg && IsA(arg, Const))
3893 : {
3894 281 : Const *carg = (Const *) arg;
3895 : bool result;
3896 :
3897 281 : switch (ntest->nulltesttype)
3898 : {
3899 238 : case IS_NULL:
3900 238 : result = carg->constisnull;
3901 238 : break;
3902 43 : case IS_NOT_NULL:
3903 43 : result = !carg->constisnull;
3904 43 : break;
3905 0 : default:
3906 0 : elog(ERROR, "unrecognized nulltesttype: %d",
3907 : (int) ntest->nulltesttype);
3908 : result = false; /* keep compiler quiet */
3909 : break;
3910 : }
3911 :
3912 281 : return makeBoolConst(result, false);
3913 : }
3914 55284 : if (!ntest->argisrow && arg &&
3915 27471 : expr_is_nonnullable(context->root, (Expr *) arg,
3916 : NOTNULL_SOURCE_HASHTABLE))
3917 : {
3918 : bool result;
3919 :
3920 536 : switch (ntest->nulltesttype)
3921 : {
3922 128 : case IS_NULL:
3923 128 : result = false;
3924 128 : break;
3925 408 : case IS_NOT_NULL:
3926 408 : result = true;
3927 408 : break;
3928 0 : default:
3929 0 : elog(ERROR, "unrecognized nulltesttype: %d",
3930 : (int) ntest->nulltesttype);
3931 : result = false; /* keep compiler quiet */
3932 : break;
3933 : }
3934 :
3935 536 : return makeBoolConst(result, false);
3936 : }
3937 :
3938 27277 : newntest = makeNode(NullTest);
3939 27277 : newntest->arg = (Expr *) arg;
3940 27277 : newntest->nulltesttype = ntest->nulltesttype;
3941 27277 : newntest->argisrow = ntest->argisrow;
3942 27277 : newntest->location = ntest->location;
3943 27277 : return (Node *) newntest;
3944 : }
3945 1689 : case T_BooleanTest:
3946 : {
3947 : /*
3948 : * This case could be folded into the generic handling used
3949 : * for ArrayExpr etc. But because the simplification logic is
3950 : * so trivial, applying evaluate_expr() to perform it would be
3951 : * a heavy overhead. BooleanTest is probably common enough to
3952 : * justify keeping this bespoke implementation.
3953 : */
3954 1689 : BooleanTest *btest = (BooleanTest *) node;
3955 : BooleanTest *newbtest;
3956 : Node *arg;
3957 :
3958 1689 : arg = eval_const_expressions_mutator((Node *) btest->arg,
3959 : context);
3960 1689 : if (arg && IsA(arg, Const))
3961 : {
3962 : /*
3963 : * If arg is Const, simplify to constant.
3964 : */
3965 195 : Const *carg = (Const *) arg;
3966 : bool result;
3967 :
3968 195 : switch (btest->booltesttype)
3969 : {
3970 0 : case IS_TRUE:
3971 0 : result = (!carg->constisnull &&
3972 0 : DatumGetBool(carg->constvalue));
3973 0 : break;
3974 195 : case IS_NOT_TRUE:
3975 390 : result = (carg->constisnull ||
3976 195 : !DatumGetBool(carg->constvalue));
3977 195 : break;
3978 0 : case IS_FALSE:
3979 0 : result = (!carg->constisnull &&
3980 0 : !DatumGetBool(carg->constvalue));
3981 0 : break;
3982 0 : case IS_NOT_FALSE:
3983 0 : result = (carg->constisnull ||
3984 0 : DatumGetBool(carg->constvalue));
3985 0 : break;
3986 0 : case IS_UNKNOWN:
3987 0 : result = carg->constisnull;
3988 0 : break;
3989 0 : case IS_NOT_UNKNOWN:
3990 0 : result = !carg->constisnull;
3991 0 : break;
3992 0 : default:
3993 0 : elog(ERROR, "unrecognized booltesttype: %d",
3994 : (int) btest->booltesttype);
3995 : result = false; /* keep compiler quiet */
3996 : break;
3997 : }
3998 :
3999 195 : return makeBoolConst(result, false);
4000 : }
4001 2988 : if (arg &&
4002 1494 : expr_is_nonnullable(context->root, (Expr *) arg,
4003 : NOTNULL_SOURCE_HASHTABLE))
4004 : {
4005 : /*
4006 : * If arg is proven non-nullable, simplify to boolean
4007 : * expression or constant.
4008 : */
4009 67 : switch (btest->booltesttype)
4010 : {
4011 20 : case IS_TRUE:
4012 : case IS_NOT_FALSE:
4013 20 : return arg;
4014 :
4015 27 : case IS_FALSE:
4016 : case IS_NOT_TRUE:
4017 27 : return (Node *) make_notclause((Expr *) arg);
4018 :
4019 10 : case IS_UNKNOWN:
4020 10 : return makeBoolConst(false, false);
4021 :
4022 10 : case IS_NOT_UNKNOWN:
4023 10 : return makeBoolConst(true, false);
4024 :
4025 0 : default:
4026 0 : elog(ERROR, "unrecognized booltesttype: %d",
4027 : (int) btest->booltesttype);
4028 : break;
4029 : }
4030 : }
4031 :
4032 1427 : newbtest = makeNode(BooleanTest);
4033 1427 : newbtest->arg = (Expr *) arg;
4034 1427 : newbtest->booltesttype = btest->booltesttype;
4035 1427 : newbtest->location = btest->location;
4036 1427 : return (Node *) newbtest;
4037 : }
4038 18529 : case T_CoerceToDomain:
4039 : {
4040 : /*
4041 : * If the domain currently has no constraints, we replace the
4042 : * CoerceToDomain node with a simple RelabelType, which is
4043 : * both far faster to execute and more amenable to later
4044 : * optimization. We must then mark the plan as needing to be
4045 : * rebuilt if the domain's constraints change.
4046 : *
4047 : * Also, in estimation mode, always replace CoerceToDomain
4048 : * nodes, effectively assuming that the coercion will succeed.
4049 : */
4050 18529 : CoerceToDomain *cdomain = (CoerceToDomain *) node;
4051 : CoerceToDomain *newcdomain;
4052 : Node *arg;
4053 :
4054 18529 : arg = eval_const_expressions_mutator((Node *) cdomain->arg,
4055 : context);
4056 18509 : if (context->estimate ||
4057 18469 : !DomainHasConstraints(cdomain->resulttype, NULL))
4058 : {
4059 : /* Record dependency, if this isn't estimation mode */
4060 12273 : if (context->root && !context->estimate)
4061 12189 : record_plan_type_dependency(context->root,
4062 : cdomain->resulttype);
4063 :
4064 : /* Generate RelabelType to substitute for CoerceToDomain */
4065 12273 : return applyRelabelType(arg,
4066 : cdomain->resulttype,
4067 : cdomain->resulttypmod,
4068 : cdomain->resultcollid,
4069 : cdomain->coercionformat,
4070 : cdomain->location,
4071 : true);
4072 : }
4073 :
4074 6236 : newcdomain = makeNode(CoerceToDomain);
4075 6236 : newcdomain->arg = (Expr *) arg;
4076 6236 : newcdomain->resulttype = cdomain->resulttype;
4077 6236 : newcdomain->resulttypmod = cdomain->resulttypmod;
4078 6236 : newcdomain->resultcollid = cdomain->resultcollid;
4079 6236 : newcdomain->coercionformat = cdomain->coercionformat;
4080 6236 : newcdomain->location = cdomain->location;
4081 6236 : return (Node *) newcdomain;
4082 : }
4083 3907 : case T_PlaceHolderVar:
4084 :
4085 : /*
4086 : * In estimation mode, just strip the PlaceHolderVar node
4087 : * altogether; this amounts to estimating that the contained value
4088 : * won't be forced to null by an outer join. In regular mode we
4089 : * just use the default behavior (ie, simplify the expression but
4090 : * leave the PlaceHolderVar node intact).
4091 : */
4092 3907 : if (context->estimate)
4093 : {
4094 710 : PlaceHolderVar *phv = (PlaceHolderVar *) node;
4095 :
4096 710 : return eval_const_expressions_mutator((Node *) phv->phexpr,
4097 : context);
4098 : }
4099 3197 : break;
4100 75 : case T_ConvertRowtypeExpr:
4101 : {
4102 75 : ConvertRowtypeExpr *cre = castNode(ConvertRowtypeExpr, node);
4103 : Node *arg;
4104 : ConvertRowtypeExpr *newcre;
4105 :
4106 75 : arg = eval_const_expressions_mutator((Node *) cre->arg,
4107 : context);
4108 :
4109 75 : newcre = makeNode(ConvertRowtypeExpr);
4110 75 : newcre->resulttype = cre->resulttype;
4111 75 : newcre->convertformat = cre->convertformat;
4112 75 : newcre->location = cre->location;
4113 :
4114 : /*
4115 : * In case of a nested ConvertRowtypeExpr, we can convert the
4116 : * leaf row directly to the topmost row format without any
4117 : * intermediate conversions. (This works because
4118 : * ConvertRowtypeExpr is used only for child->parent
4119 : * conversion in inheritance trees, which works by exact match
4120 : * of column name, and a column absent in an intermediate
4121 : * result can't be present in the final result.)
4122 : *
4123 : * No need to check more than one level deep, because the
4124 : * above recursion will have flattened anything else.
4125 : */
4126 75 : if (arg != NULL && IsA(arg, ConvertRowtypeExpr))
4127 : {
4128 10 : ConvertRowtypeExpr *argcre = (ConvertRowtypeExpr *) arg;
4129 :
4130 10 : arg = (Node *) argcre->arg;
4131 :
4132 : /*
4133 : * Make sure an outer implicit conversion can't hide an
4134 : * inner explicit one.
4135 : */
4136 10 : if (newcre->convertformat == COERCE_IMPLICIT_CAST)
4137 0 : newcre->convertformat = argcre->convertformat;
4138 : }
4139 :
4140 75 : newcre->arg = (Expr *) arg;
4141 :
4142 75 : if (arg != NULL && IsA(arg, Const))
4143 15 : return ece_evaluate_expr((Node *) newcre);
4144 60 : return (Node *) newcre;
4145 : }
4146 5204036 : default:
4147 5204036 : break;
4148 : }
4149 :
4150 : /*
4151 : * For any node type not handled above, copy the node unchanged but
4152 : * const-simplify its subexpressions. This is the correct thing for node
4153 : * types whose behavior might change between planning and execution, such
4154 : * as CurrentOfExpr. It's also a safe default for new node types not
4155 : * known to this routine.
4156 : */
4157 5208576 : return ece_generic_processing(node);
4158 : }
4159 :
4160 : /*
4161 : * Subroutine for eval_const_expressions: check for non-Const nodes.
4162 : *
4163 : * We can abort recursion immediately on finding a non-Const node. This is
4164 : * critical for performance, else eval_const_expressions_mutator would take
4165 : * O(N^2) time on non-simplifiable trees. However, we do need to descend
4166 : * into List nodes since expression_tree_walker sometimes invokes the walker
4167 : * function directly on List subtrees.
4168 : */
4169 : static bool
4170 167851 : contain_non_const_walker(Node *node, void *context)
4171 : {
4172 167851 : if (node == NULL)
4173 596 : return false;
4174 167255 : if (IsA(node, Const))
4175 86391 : return false;
4176 80864 : if (IsA(node, List))
4177 26556 : return expression_tree_walker(node, contain_non_const_walker, context);
4178 : /* Otherwise, abort the tree traversal and return true */
4179 54308 : return true;
4180 : }
4181 :
4182 : /*
4183 : * Subroutine for eval_const_expressions: check if a function is OK to evaluate
4184 : */
4185 : static bool
4186 300 : ece_function_is_safe(Oid funcid, eval_const_expressions_context *context)
4187 : {
4188 300 : char provolatile = func_volatile(funcid);
4189 :
4190 : /*
4191 : * Ordinarily we are only allowed to simplify immutable functions. But for
4192 : * purposes of estimation, we consider it okay to simplify functions that
4193 : * are merely stable; the risk that the result might change from planning
4194 : * time to execution time is worth taking in preference to not being able
4195 : * to estimate the value at all.
4196 : */
4197 300 : if (provolatile == PROVOLATILE_IMMUTABLE)
4198 300 : return true;
4199 0 : if (context->estimate && provolatile == PROVOLATILE_STABLE)
4200 0 : return true;
4201 0 : return false;
4202 : }
4203 :
4204 : /*
4205 : * Subroutine for eval_const_expressions: process arguments of an OR clause
4206 : *
4207 : * This includes flattening of nested ORs as well as recursion to
4208 : * eval_const_expressions to simplify the OR arguments.
4209 : *
4210 : * After simplification, OR arguments are handled as follows:
4211 : * non constant: keep
4212 : * FALSE: drop (does not affect result)
4213 : * TRUE: force result to TRUE
4214 : * NULL: keep only one
4215 : * We must keep one NULL input because OR expressions evaluate to NULL when no
4216 : * input is TRUE and at least one is NULL. We don't actually include the NULL
4217 : * here, that's supposed to be done by the caller.
4218 : *
4219 : * The output arguments *haveNull and *forceTrue must be initialized false
4220 : * by the caller. They will be set true if a NULL constant or TRUE constant,
4221 : * respectively, is detected anywhere in the argument list.
4222 : */
4223 : static List *
4224 15328 : simplify_or_arguments(List *args,
4225 : eval_const_expressions_context *context,
4226 : bool *haveNull, bool *forceTrue)
4227 : {
4228 15328 : List *newargs = NIL;
4229 : List *unprocessed_args;
4230 :
4231 : /*
4232 : * We want to ensure that any OR immediately beneath another OR gets
4233 : * flattened into a single OR-list, so as to simplify later reasoning.
4234 : *
4235 : * To avoid stack overflow from recursion of eval_const_expressions, we
4236 : * resort to some tenseness here: we keep a list of not-yet-processed
4237 : * inputs, and handle flattening of nested ORs by prepending to the to-do
4238 : * list instead of recursing. Now that the parser generates N-argument
4239 : * ORs from simple lists, this complexity is probably less necessary than
4240 : * it once was, but we might as well keep the logic.
4241 : */
4242 15328 : unprocessed_args = list_copy(args);
4243 49684 : while (unprocessed_args)
4244 : {
4245 34462 : Node *arg = (Node *) linitial(unprocessed_args);
4246 :
4247 34462 : unprocessed_args = list_delete_first(unprocessed_args);
4248 :
4249 : /* flatten nested ORs as per above comment */
4250 34462 : if (is_orclause(arg))
4251 7 : {
4252 7 : List *subargs = ((BoolExpr *) arg)->args;
4253 7 : List *oldlist = unprocessed_args;
4254 :
4255 7 : unprocessed_args = list_concat_copy(subargs, unprocessed_args);
4256 : /* perhaps-overly-tense code to avoid leaking old lists */
4257 7 : list_free(oldlist);
4258 7 : continue;
4259 : }
4260 :
4261 : /* If it's not an OR, simplify it */
4262 34455 : arg = eval_const_expressions_mutator(arg, context);
4263 :
4264 : /*
4265 : * It is unlikely but not impossible for simplification of a non-OR
4266 : * clause to produce an OR. Recheck, but don't be too tense about it
4267 : * since it's not a mainstream case. In particular we don't worry
4268 : * about const-simplifying the input twice, nor about list leakage.
4269 : */
4270 34455 : if (is_orclause(arg))
4271 0 : {
4272 0 : List *subargs = ((BoolExpr *) arg)->args;
4273 :
4274 0 : unprocessed_args = list_concat_copy(subargs, unprocessed_args);
4275 0 : continue;
4276 : }
4277 :
4278 : /*
4279 : * OK, we have a const-simplified non-OR argument. Process it per
4280 : * comments above.
4281 : */
4282 34455 : if (IsA(arg, Const))
4283 3959 : {
4284 4065 : Const *const_input = (Const *) arg;
4285 :
4286 4065 : if (const_input->constisnull)
4287 3813 : *haveNull = true;
4288 252 : else if (DatumGetBool(const_input->constvalue))
4289 : {
4290 106 : *forceTrue = true;
4291 :
4292 : /*
4293 : * Once we detect a TRUE result we can just exit the loop
4294 : * immediately. However, if we ever add a notion of
4295 : * non-removable functions, we'd need to keep scanning.
4296 : */
4297 106 : return NIL;
4298 : }
4299 : /* otherwise, we can drop the constant-false input */
4300 3959 : continue;
4301 : }
4302 :
4303 : /* else emit the simplified arg into the result list */
4304 30390 : newargs = lappend(newargs, arg);
4305 : }
4306 :
4307 15222 : return newargs;
4308 : }
4309 :
4310 : /*
4311 : * Subroutine for eval_const_expressions: process arguments of an AND clause
4312 : *
4313 : * This includes flattening of nested ANDs as well as recursion to
4314 : * eval_const_expressions to simplify the AND arguments.
4315 : *
4316 : * After simplification, AND arguments are handled as follows:
4317 : * non constant: keep
4318 : * TRUE: drop (does not affect result)
4319 : * FALSE: force result to FALSE
4320 : * NULL: keep only one
4321 : * We must keep one NULL input because AND expressions evaluate to NULL when
4322 : * no input is FALSE and at least one is NULL. We don't actually include the
4323 : * NULL here, that's supposed to be done by the caller.
4324 : *
4325 : * The output arguments *haveNull and *forceFalse must be initialized false
4326 : * by the caller. They will be set true if a null constant or false constant,
4327 : * respectively, is detected anywhere in the argument list.
4328 : */
4329 : static List *
4330 116558 : simplify_and_arguments(List *args,
4331 : eval_const_expressions_context *context,
4332 : bool *haveNull, bool *forceFalse)
4333 : {
4334 116558 : List *newargs = NIL;
4335 : List *unprocessed_args;
4336 :
4337 : /* See comments in simplify_or_arguments */
4338 116558 : unprocessed_args = list_copy(args);
4339 423746 : while (unprocessed_args)
4340 : {
4341 307843 : Node *arg = (Node *) linitial(unprocessed_args);
4342 :
4343 307843 : unprocessed_args = list_delete_first(unprocessed_args);
4344 :
4345 : /* flatten nested ANDs as per above comment */
4346 307843 : if (is_andclause(arg))
4347 4035 : {
4348 4035 : List *subargs = ((BoolExpr *) arg)->args;
4349 4035 : List *oldlist = unprocessed_args;
4350 :
4351 4035 : unprocessed_args = list_concat_copy(subargs, unprocessed_args);
4352 : /* perhaps-overly-tense code to avoid leaking old lists */
4353 4035 : list_free(oldlist);
4354 4035 : continue;
4355 : }
4356 :
4357 : /* If it's not an AND, simplify it */
4358 303808 : arg = eval_const_expressions_mutator(arg, context);
4359 :
4360 : /*
4361 : * It is unlikely but not impossible for simplification of a non-AND
4362 : * clause to produce an AND. Recheck, but don't be too tense about it
4363 : * since it's not a mainstream case. In particular we don't worry
4364 : * about const-simplifying the input twice, nor about list leakage.
4365 : */
4366 303808 : if (is_andclause(arg))
4367 30 : {
4368 30 : List *subargs = ((BoolExpr *) arg)->args;
4369 :
4370 30 : unprocessed_args = list_concat_copy(subargs, unprocessed_args);
4371 30 : continue;
4372 : }
4373 :
4374 : /*
4375 : * OK, we have a const-simplified non-AND argument. Process it per
4376 : * comments above.
4377 : */
4378 303778 : if (IsA(arg, Const))
4379 1238 : {
4380 1893 : Const *const_input = (Const *) arg;
4381 :
4382 1893 : if (const_input->constisnull)
4383 35 : *haveNull = true;
4384 1858 : else if (!DatumGetBool(const_input->constvalue))
4385 : {
4386 655 : *forceFalse = true;
4387 :
4388 : /*
4389 : * Once we detect a FALSE result we can just exit the loop
4390 : * immediately. However, if we ever add a notion of
4391 : * non-removable functions, we'd need to keep scanning.
4392 : */
4393 655 : return NIL;
4394 : }
4395 : /* otherwise, we can drop the constant-true input */
4396 1238 : continue;
4397 : }
4398 :
4399 : /* else emit the simplified arg into the result list */
4400 301885 : newargs = lappend(newargs, arg);
4401 : }
4402 :
4403 115903 : return newargs;
4404 : }
4405 :
4406 : /*
4407 : * Subroutine for eval_const_expressions: try to simplify boolean equality
4408 : * or inequality condition
4409 : *
4410 : * Inputs are the operator OID and the simplified arguments to the operator.
4411 : * Returns a simplified expression if successful, or NULL if cannot
4412 : * simplify the expression.
4413 : *
4414 : * The idea here is to reduce "x = true" to "x" and "x = false" to "NOT x",
4415 : * or similarly "x <> true" to "NOT x" and "x <> false" to "x".
4416 : * This is only marginally useful in itself, but doing it in constant folding
4417 : * ensures that we will recognize these forms as being equivalent in, for
4418 : * example, partial index matching.
4419 : *
4420 : * We come here only if simplify_function has failed; therefore we cannot
4421 : * see two constant inputs, nor a constant-NULL input.
4422 : */
4423 : static Node *
4424 1764 : simplify_boolean_equality(Oid opno, List *args)
4425 : {
4426 : Node *leftop;
4427 : Node *rightop;
4428 :
4429 : Assert(list_length(args) == 2);
4430 1764 : leftop = linitial(args);
4431 1764 : rightop = lsecond(args);
4432 1764 : if (leftop && IsA(leftop, Const))
4433 : {
4434 : Assert(!((Const *) leftop)->constisnull);
4435 0 : if (opno == BooleanEqualOperator)
4436 : {
4437 0 : if (DatumGetBool(((Const *) leftop)->constvalue))
4438 0 : return rightop; /* true = foo */
4439 : else
4440 0 : return negate_clause(rightop); /* false = foo */
4441 : }
4442 : else
4443 : {
4444 0 : if (DatumGetBool(((Const *) leftop)->constvalue))
4445 0 : return negate_clause(rightop); /* true <> foo */
4446 : else
4447 0 : return rightop; /* false <> foo */
4448 : }
4449 : }
4450 1764 : if (rightop && IsA(rightop, Const))
4451 : {
4452 : Assert(!((Const *) rightop)->constisnull);
4453 1279 : if (opno == BooleanEqualOperator)
4454 : {
4455 1224 : if (DatumGetBool(((Const *) rightop)->constvalue))
4456 182 : return leftop; /* foo = true */
4457 : else
4458 1042 : return negate_clause(leftop); /* foo = false */
4459 : }
4460 : else
4461 : {
4462 55 : if (DatumGetBool(((Const *) rightop)->constvalue))
4463 50 : return negate_clause(leftop); /* foo <> true */
4464 : else
4465 5 : return leftop; /* foo <> false */
4466 : }
4467 : }
4468 485 : return NULL;
4469 : }
4470 :
4471 : /*
4472 : * Subroutine for eval_const_expressions: try to simplify a function call
4473 : * (which might originally have been an operator; we don't care)
4474 : *
4475 : * Inputs are the function OID, actual result type OID (which is needed for
4476 : * polymorphic functions), result typmod, result collation, the input
4477 : * collation to use for the function, the original argument list (not
4478 : * const-simplified yet, unless process_args is false), and some flags;
4479 : * also the context data for eval_const_expressions.
4480 : *
4481 : * Returns a simplified expression if successful, or NULL if cannot
4482 : * simplify the function call.
4483 : *
4484 : * This function is also responsible for converting named-notation argument
4485 : * lists into positional notation and/or adding any needed default argument
4486 : * expressions; which is a bit grotty, but it avoids extra fetches of the
4487 : * function's pg_proc tuple. For this reason, the args list is
4488 : * pass-by-reference. Conversion and const-simplification of the args list
4489 : * will be done even if simplification of the function call itself is not
4490 : * possible.
4491 : */
4492 : static Expr *
4493 963406 : simplify_function(Oid funcid, Oid result_type, int32 result_typmod,
4494 : Oid result_collid, Oid input_collid, List **args_p,
4495 : bool funcvariadic, bool process_args, bool allow_non_const,
4496 : eval_const_expressions_context *context)
4497 : {
4498 963406 : List *args = *args_p;
4499 : HeapTuple func_tuple;
4500 : Form_pg_proc func_form;
4501 : Expr *newexpr;
4502 :
4503 : /*
4504 : * We have three strategies for simplification: execute the function to
4505 : * deliver a constant result, use a transform function to generate a
4506 : * substitute node tree, or expand in-line the body of the function
4507 : * definition (which only works for simple SQL-language functions, but
4508 : * that is a common case). Each case needs access to the function's
4509 : * pg_proc tuple, so fetch it just once.
4510 : *
4511 : * Note: the allow_non_const flag suppresses both the second and third
4512 : * strategies; so if !allow_non_const, simplify_function can only return a
4513 : * Const or NULL. Argument-list rewriting happens anyway, though.
4514 : */
4515 963406 : func_tuple = SearchSysCache1(PROCOID, ObjectIdGetDatum(funcid));
4516 963406 : if (!HeapTupleIsValid(func_tuple))
4517 0 : elog(ERROR, "cache lookup failed for function %u", funcid);
4518 963406 : func_form = (Form_pg_proc) GETSTRUCT(func_tuple);
4519 :
4520 : /*
4521 : * Process the function arguments, unless the caller did it already.
4522 : *
4523 : * Here we must deal with named or defaulted arguments, and then
4524 : * recursively apply eval_const_expressions to the whole argument list.
4525 : */
4526 963406 : if (process_args)
4527 : {
4528 961485 : args = expand_function_arguments(args, false, result_type, func_tuple);
4529 961485 : args = (List *) expression_tree_mutator((Node *) args,
4530 : eval_const_expressions_mutator,
4531 : context);
4532 : /* Argument processing done, give it back to the caller */
4533 961408 : *args_p = args;
4534 : }
4535 :
4536 : /* Now attempt simplification of the function call proper. */
4537 :
4538 963329 : newexpr = evaluate_function(funcid, result_type, result_typmod,
4539 : result_collid, input_collid,
4540 : args, funcvariadic,
4541 : func_tuple, context);
4542 :
4543 960708 : if (!newexpr && allow_non_const && OidIsValid(func_form->prosupport))
4544 : {
4545 : /*
4546 : * Build a SupportRequestSimplify node to pass to the support
4547 : * function, pointing to a dummy FuncExpr node containing the
4548 : * simplified arg list. We use this approach to present a uniform
4549 : * interface to the support function regardless of how the target
4550 : * function is actually being invoked.
4551 : */
4552 : SupportRequestSimplify req;
4553 : FuncExpr fexpr;
4554 :
4555 27120 : fexpr.xpr.type = T_FuncExpr;
4556 27120 : fexpr.funcid = funcid;
4557 27120 : fexpr.funcresulttype = result_type;
4558 27120 : fexpr.funcretset = func_form->proretset;
4559 27120 : fexpr.funcvariadic = funcvariadic;
4560 27120 : fexpr.funcformat = COERCE_EXPLICIT_CALL;
4561 27120 : fexpr.funccollid = result_collid;
4562 27120 : fexpr.inputcollid = input_collid;
4563 27120 : fexpr.args = args;
4564 27120 : fexpr.location = -1;
4565 :
4566 27120 : req.type = T_SupportRequestSimplify;
4567 27120 : req.root = context->root;
4568 27120 : req.fcall = &fexpr;
4569 :
4570 : newexpr = (Expr *)
4571 27120 : DatumGetPointer(OidFunctionCall1(func_form->prosupport,
4572 : PointerGetDatum(&req)));
4573 :
4574 : /* catch a possible API misunderstanding */
4575 : Assert(newexpr != (Expr *) &fexpr);
4576 : }
4577 :
4578 960708 : if (!newexpr && allow_non_const)
4579 828400 : newexpr = inline_function(funcid, result_type, result_collid,
4580 : input_collid, args, funcvariadic,
4581 : func_tuple, context);
4582 :
4583 960699 : ReleaseSysCache(func_tuple);
4584 :
4585 960699 : return newexpr;
4586 : }
4587 :
4588 : /*
4589 : * simplify_aggref
4590 : * Call the Aggref.aggfnoid's prosupport function to allow it to
4591 : * determine if simplification of the Aggref is possible. Returns the
4592 : * newly simplified node if conversion took place; otherwise, returns the
4593 : * original Aggref.
4594 : *
4595 : * See SupportRequestSimplifyAggref comments in supportnodes.h for further
4596 : * details.
4597 : */
4598 : static Node *
4599 38101 : simplify_aggref(Aggref *aggref, eval_const_expressions_context *context)
4600 : {
4601 38101 : Oid prosupport = get_func_support(aggref->aggfnoid);
4602 :
4603 38101 : if (OidIsValid(prosupport))
4604 : {
4605 : SupportRequestSimplifyAggref req;
4606 : Node *newnode;
4607 :
4608 : /*
4609 : * Build a SupportRequestSimplifyAggref node to pass to the support
4610 : * function.
4611 : */
4612 14016 : req.type = T_SupportRequestSimplifyAggref;
4613 14016 : req.root = context->root;
4614 14016 : req.aggref = aggref;
4615 :
4616 14016 : newnode = (Node *) DatumGetPointer(OidFunctionCall1(prosupport,
4617 : PointerGetDatum(&req)));
4618 :
4619 : /*
4620 : * We expect the support function to return either a new Node or NULL
4621 : * (when simplification isn't possible).
4622 : */
4623 : Assert(newnode != (Node *) aggref || newnode == NULL);
4624 :
4625 14016 : if (newnode != NULL)
4626 297 : return newnode;
4627 : }
4628 :
4629 37804 : return (Node *) aggref;
4630 : }
4631 :
4632 : /*
4633 : * var_is_nonnullable: check to see if the Var cannot be NULL
4634 : *
4635 : * If the Var is defined NOT NULL and meanwhile is not nulled by any outer
4636 : * joins or grouping sets, then we can know that it cannot be NULL.
4637 : *
4638 : * "source" specifies where we should look for NOT NULL proofs.
4639 : */
4640 : bool
4641 25603 : var_is_nonnullable(PlannerInfo *root, Var *var, NotNullSource source)
4642 : {
4643 : Assert(IsA(var, Var));
4644 :
4645 : /* skip upper-level Vars */
4646 25603 : if (var->varlevelsup != 0)
4647 55 : return false;
4648 :
4649 : /* could the Var be nulled by any outer joins or grouping sets? */
4650 25548 : if (!bms_is_empty(var->varnullingrels))
4651 3591 : return false;
4652 :
4653 : /*
4654 : * If the Var has a non-default returning type, it could be NULL
4655 : * regardless of any NOT NULL constraint. For example, OLD.col is NULL
4656 : * for INSERT, and NEW.col is NULL for DELETE.
4657 : */
4658 21957 : if (var->varreturningtype != VAR_RETURNING_DEFAULT)
4659 20 : return false;
4660 :
4661 : /* system columns cannot be NULL */
4662 21937 : if (var->varattno < 0)
4663 30 : return true;
4664 :
4665 : /* we don't trust whole-row Vars */
4666 21907 : if (var->varattno == 0)
4667 48 : return false;
4668 :
4669 : /* Check if the Var is defined as NOT NULL. */
4670 21859 : switch (source)
4671 : {
4672 6272 : case NOTNULL_SOURCE_RELOPT:
4673 : {
4674 : /*
4675 : * We retrieve the column NOT NULL constraint information from
4676 : * the corresponding RelOptInfo.
4677 : */
4678 : RelOptInfo *rel;
4679 : Bitmapset *notnullattnums;
4680 :
4681 6272 : rel = find_base_rel(root, var->varno);
4682 6272 : notnullattnums = rel->notnullattnums;
4683 :
4684 6272 : return bms_is_member(var->varattno, notnullattnums);
4685 : }
4686 15472 : case NOTNULL_SOURCE_HASHTABLE:
4687 : {
4688 : /*
4689 : * We retrieve the column NOT NULL constraint information from
4690 : * the hash table.
4691 : */
4692 : RangeTblEntry *rte;
4693 : Bitmapset *notnullattnums;
4694 :
4695 15472 : rte = planner_rt_fetch(var->varno, root);
4696 :
4697 : /* We can only reason about ordinary relations */
4698 15472 : if (rte->rtekind != RTE_RELATION)
4699 1394 : return false;
4700 :
4701 : /*
4702 : * We must skip inheritance parent tables, as some child
4703 : * tables may have a NOT NULL constraint for a column while
4704 : * others may not. This cannot happen with partitioned
4705 : * tables, though.
4706 : */
4707 14078 : if (rte->inh && rte->relkind != RELKIND_PARTITIONED_TABLE)
4708 175 : return false;
4709 :
4710 13903 : notnullattnums = find_relation_notnullatts(root, rte->relid);
4711 :
4712 13903 : return bms_is_member(var->varattno, notnullattnums);
4713 : }
4714 115 : case NOTNULL_SOURCE_CATALOG:
4715 : {
4716 : /*
4717 : * We check the attnullability field in the tuple descriptor.
4718 : * This is necessary rather than checking the attnotnull field
4719 : * from the attribute relation, because attnotnull is also set
4720 : * for invalid (NOT VALID) NOT NULL constraints, which do not
4721 : * guarantee the absence of NULLs.
4722 : */
4723 : RangeTblEntry *rte;
4724 : Relation rel;
4725 : CompactAttribute *attr;
4726 : bool result;
4727 :
4728 115 : rte = planner_rt_fetch(var->varno, root);
4729 :
4730 : /* We can only reason about ordinary relations */
4731 115 : if (rte->rtekind != RTE_RELATION)
4732 0 : return false;
4733 :
4734 : /*
4735 : * We must skip inheritance parent tables, as some child
4736 : * tables may have a NOT NULL constraint for a column while
4737 : * others may not. This cannot happen with partitioned
4738 : * tables, though.
4739 : *
4740 : * Note that we need to check if the relation actually has any
4741 : * children, as we might not have done that yet.
4742 : */
4743 115 : if (rte->inh && has_subclass(rte->relid) &&
4744 0 : rte->relkind != RELKIND_PARTITIONED_TABLE)
4745 0 : return false;
4746 :
4747 : /* We need not lock the relation since it was already locked */
4748 115 : rel = table_open(rte->relid, NoLock);
4749 115 : attr = TupleDescCompactAttr(RelationGetDescr(rel),
4750 115 : var->varattno - 1);
4751 115 : result = (attr->attnullability == ATTNULLABLE_VALID);
4752 115 : table_close(rel, NoLock);
4753 :
4754 115 : return result;
4755 : }
4756 0 : default:
4757 0 : elog(ERROR, "unrecognized NotNullSource: %d",
4758 : (int) source);
4759 : break;
4760 : }
4761 :
4762 : return false;
4763 : }
4764 :
4765 : /*
4766 : * expr_is_nonnullable: check to see if the Expr cannot be NULL
4767 : *
4768 : * Returns true iff the given 'expr' cannot produce SQL NULLs.
4769 : *
4770 : * source: specifies where we should look for NOT NULL proofs for Vars.
4771 : * - NOTNULL_SOURCE_RELOPT: Used when RelOptInfos have been generated. We
4772 : * retrieve nullability information directly from the RelOptInfo corresponding
4773 : * to the Var.
4774 : * - NOTNULL_SOURCE_HASHTABLE: Used when RelOptInfos are not yet available,
4775 : * but we have already collected relation-level not-null constraints into the
4776 : * global hash table.
4777 : * - NOTNULL_SOURCE_CATALOG: Used for raw parse trees where neither
4778 : * RelOptInfos nor the hash table are available. In this case, we check the
4779 : * column's attnullability in the tuple descriptor.
4780 : *
4781 : * For now, we support only a limited set of expression types. Support for
4782 : * additional node types can be added in the future.
4783 : */
4784 : bool
4785 42470 : expr_is_nonnullable(PlannerInfo *root, Expr *expr, NotNullSource source)
4786 : {
4787 : /* since this function recurses, it could be driven to stack overflow */
4788 42470 : check_stack_depth();
4789 :
4790 42470 : switch (nodeTag(expr))
4791 : {
4792 37460 : case T_Var:
4793 : {
4794 37460 : if (root)
4795 25603 : return var_is_nonnullable(root, (Var *) expr, source);
4796 : }
4797 11857 : break;
4798 417 : case T_Const:
4799 417 : return !((Const *) expr)->constisnull;
4800 165 : case T_CoalesceExpr:
4801 : {
4802 : /*
4803 : * A CoalesceExpr returns NULL if and only if all its
4804 : * arguments are NULL. Therefore, we can determine that a
4805 : * CoalesceExpr cannot be NULL if at least one of its
4806 : * arguments can be proven non-nullable.
4807 : */
4808 165 : CoalesceExpr *coalesceexpr = (CoalesceExpr *) expr;
4809 :
4810 570 : foreach_ptr(Expr, arg, coalesceexpr->args)
4811 : {
4812 330 : if (expr_is_nonnullable(root, arg, source))
4813 45 : return true;
4814 : }
4815 : }
4816 120 : break;
4817 15 : case T_MinMaxExpr:
4818 : {
4819 : /*
4820 : * Like CoalesceExpr, a MinMaxExpr returns NULL only if all
4821 : * its arguments evaluate to NULL.
4822 : */
4823 15 : MinMaxExpr *minmaxexpr = (MinMaxExpr *) expr;
4824 :
4825 50 : foreach_ptr(Expr, arg, minmaxexpr->args)
4826 : {
4827 30 : if (expr_is_nonnullable(root, arg, source))
4828 5 : return true;
4829 : }
4830 : }
4831 10 : break;
4832 81 : case T_CaseExpr:
4833 : {
4834 : /*
4835 : * A CASE expression is non-nullable if all branch results are
4836 : * non-nullable. We must also verify that the default result
4837 : * (ELSE) exists and is non-nullable.
4838 : */
4839 81 : CaseExpr *caseexpr = (CaseExpr *) expr;
4840 :
4841 : /* The default result must be present and non-nullable */
4842 81 : if (caseexpr->defresult == NULL ||
4843 81 : !expr_is_nonnullable(root, caseexpr->defresult, source))
4844 66 : return false;
4845 :
4846 : /* All branch results must be non-nullable */
4847 25 : foreach_ptr(CaseWhen, casewhen, caseexpr->args)
4848 : {
4849 15 : if (!expr_is_nonnullable(root, casewhen->result, source))
4850 10 : return false;
4851 : }
4852 :
4853 5 : return true;
4854 : }
4855 : break;
4856 5 : case T_ArrayExpr:
4857 : {
4858 : /*
4859 : * An ARRAY[] expression always returns a valid Array object,
4860 : * even if it is empty (ARRAY[]) or contains NULLs
4861 : * (ARRAY[NULL]). It never evaluates to a SQL NULL.
4862 : */
4863 5 : return true;
4864 : }
4865 7 : case T_NullTest:
4866 : {
4867 : /*
4868 : * An IS NULL / IS NOT NULL expression always returns a
4869 : * boolean value. It never returns SQL NULL.
4870 : */
4871 7 : return true;
4872 : }
4873 5 : case T_BooleanTest:
4874 : {
4875 : /*
4876 : * A BooleanTest expression always evaluates to a boolean
4877 : * value. It never returns SQL NULL.
4878 : */
4879 5 : return true;
4880 : }
4881 5 : case T_DistinctExpr:
4882 : {
4883 : /*
4884 : * IS DISTINCT FROM never returns NULL, effectively acting as
4885 : * though NULL were a normal data value.
4886 : */
4887 5 : return true;
4888 : }
4889 63 : case T_RelabelType:
4890 : {
4891 : /*
4892 : * RelabelType does not change the nullability of the data.
4893 : * The result is non-nullable if and only if the argument is
4894 : * non-nullable.
4895 : */
4896 63 : return expr_is_nonnullable(root, ((RelabelType *) expr)->arg,
4897 : source);
4898 : }
4899 4247 : default:
4900 4247 : break;
4901 : }
4902 :
4903 16234 : return false;
4904 : }
4905 :
4906 : /*
4907 : * expand_function_arguments: convert named-notation args to positional args
4908 : * and/or insert default args, as needed
4909 : *
4910 : * Returns a possibly-transformed version of the args list.
4911 : *
4912 : * If include_out_arguments is true, then the args list and the result
4913 : * include OUT arguments.
4914 : *
4915 : * The expected result type of the call must be given, for sanity-checking
4916 : * purposes. Also, we ask the caller to provide the function's actual
4917 : * pg_proc tuple, not just its OID.
4918 : *
4919 : * If we need to change anything, the input argument list is copied, not
4920 : * modified.
4921 : *
4922 : * Note: this gets applied to operator argument lists too, even though the
4923 : * cases it handles should never occur there. This should be OK since it
4924 : * will fall through very quickly if there's nothing to do.
4925 : */
4926 : List *
4927 964852 : expand_function_arguments(List *args, bool include_out_arguments,
4928 : Oid result_type, HeapTuple func_tuple)
4929 : {
4930 964852 : Form_pg_proc funcform = (Form_pg_proc) GETSTRUCT(func_tuple);
4931 964852 : Oid *proargtypes = funcform->proargtypes.values;
4932 964852 : int pronargs = funcform->pronargs;
4933 964852 : bool has_named_args = false;
4934 : ListCell *lc;
4935 :
4936 : /*
4937 : * If we are asked to match to OUT arguments, then use the proallargtypes
4938 : * array (which includes those); otherwise use proargtypes (which
4939 : * doesn't). Of course, if proallargtypes is null, we always use
4940 : * proargtypes. (Fetching proallargtypes is annoyingly expensive
4941 : * considering that we may have nothing to do here, but fortunately the
4942 : * common case is include_out_arguments == false.)
4943 : */
4944 964852 : if (include_out_arguments)
4945 : {
4946 : Datum proallargtypes;
4947 : bool isNull;
4948 :
4949 290 : proallargtypes = SysCacheGetAttr(PROCOID, func_tuple,
4950 : Anum_pg_proc_proallargtypes,
4951 : &isNull);
4952 290 : if (!isNull)
4953 : {
4954 118 : ArrayType *arr = DatumGetArrayTypeP(proallargtypes);
4955 :
4956 118 : pronargs = ARR_DIMS(arr)[0];
4957 118 : if (ARR_NDIM(arr) != 1 ||
4958 118 : pronargs < 0 ||
4959 118 : ARR_HASNULL(arr) ||
4960 118 : ARR_ELEMTYPE(arr) != OIDOID)
4961 0 : elog(ERROR, "proallargtypes is not a 1-D Oid array or it contains nulls");
4962 : Assert(pronargs >= funcform->pronargs);
4963 118 : proargtypes = (Oid *) ARR_DATA_PTR(arr);
4964 : }
4965 : }
4966 :
4967 : /* Do we have any named arguments? */
4968 2663150 : foreach(lc, args)
4969 : {
4970 1707605 : Node *arg = (Node *) lfirst(lc);
4971 :
4972 1707605 : if (IsA(arg, NamedArgExpr))
4973 : {
4974 9307 : has_named_args = true;
4975 9307 : break;
4976 : }
4977 : }
4978 :
4979 : /* If so, we must apply reorder_function_arguments */
4980 964852 : if (has_named_args)
4981 : {
4982 9307 : args = reorder_function_arguments(args, pronargs, func_tuple);
4983 : /* Recheck argument types and add casts if needed */
4984 9307 : recheck_cast_function_args(args, result_type,
4985 : proargtypes, pronargs,
4986 : func_tuple);
4987 : }
4988 955545 : else if (list_length(args) < pronargs)
4989 : {
4990 : /* No named args, but we seem to be short some defaults */
4991 5495 : args = add_function_defaults(args, pronargs, func_tuple);
4992 : /* Recheck argument types and add casts if needed */
4993 5495 : recheck_cast_function_args(args, result_type,
4994 : proargtypes, pronargs,
4995 : func_tuple);
4996 : }
4997 :
4998 964852 : return args;
4999 : }
5000 :
5001 : /*
5002 : * reorder_function_arguments: convert named-notation args to positional args
5003 : *
5004 : * This function also inserts default argument values as needed, since it's
5005 : * impossible to form a truly valid positional call without that.
5006 : */
5007 : static List *
5008 9307 : reorder_function_arguments(List *args, int pronargs, HeapTuple func_tuple)
5009 : {
5010 9307 : Form_pg_proc funcform = (Form_pg_proc) GETSTRUCT(func_tuple);
5011 9307 : int nargsprovided = list_length(args);
5012 : Node *argarray[FUNC_MAX_ARGS];
5013 : ListCell *lc;
5014 : int i;
5015 :
5016 : Assert(nargsprovided <= pronargs);
5017 9307 : if (pronargs < 0 || pronargs > FUNC_MAX_ARGS)
5018 0 : elog(ERROR, "too many function arguments");
5019 9307 : memset(argarray, 0, pronargs * sizeof(Node *));
5020 :
5021 : /* Deconstruct the argument list into an array indexed by argnumber */
5022 9307 : i = 0;
5023 37847 : foreach(lc, args)
5024 : {
5025 28540 : Node *arg = (Node *) lfirst(lc);
5026 :
5027 28540 : if (!IsA(arg, NamedArgExpr))
5028 : {
5029 : /* positional argument, assumed to precede all named args */
5030 : Assert(argarray[i] == NULL);
5031 1842 : argarray[i++] = arg;
5032 : }
5033 : else
5034 : {
5035 26698 : NamedArgExpr *na = (NamedArgExpr *) arg;
5036 :
5037 : Assert(na->argnumber >= 0 && na->argnumber < pronargs);
5038 : Assert(argarray[na->argnumber] == NULL);
5039 26698 : argarray[na->argnumber] = (Node *) na->arg;
5040 : }
5041 : }
5042 :
5043 : /*
5044 : * Fetch default expressions, if needed, and insert into array at proper
5045 : * locations (they aren't necessarily consecutive or all used)
5046 : */
5047 9307 : if (nargsprovided < pronargs)
5048 : {
5049 4396 : List *defaults = fetch_function_defaults(func_tuple);
5050 :
5051 4396 : i = pronargs - funcform->pronargdefaults;
5052 24462 : foreach(lc, defaults)
5053 : {
5054 20066 : if (argarray[i] == NULL)
5055 8737 : argarray[i] = (Node *) lfirst(lc);
5056 20066 : i++;
5057 : }
5058 : }
5059 :
5060 : /* Now reconstruct the args list in proper order */
5061 9307 : args = NIL;
5062 46584 : for (i = 0; i < pronargs; i++)
5063 : {
5064 : Assert(argarray[i] != NULL);
5065 37277 : args = lappend(args, argarray[i]);
5066 : }
5067 :
5068 9307 : return args;
5069 : }
5070 :
5071 : /*
5072 : * add_function_defaults: add missing function arguments from its defaults
5073 : *
5074 : * This is used only when the argument list was positional to begin with,
5075 : * and so we know we just need to add defaults at the end.
5076 : */
5077 : static List *
5078 5495 : add_function_defaults(List *args, int pronargs, HeapTuple func_tuple)
5079 : {
5080 5495 : int nargsprovided = list_length(args);
5081 : List *defaults;
5082 : int ndelete;
5083 :
5084 : /* Get all the default expressions from the pg_proc tuple */
5085 5495 : defaults = fetch_function_defaults(func_tuple);
5086 :
5087 : /* Delete any unused defaults from the list */
5088 5495 : ndelete = nargsprovided + list_length(defaults) - pronargs;
5089 5495 : if (ndelete < 0)
5090 0 : elog(ERROR, "not enough default arguments");
5091 5495 : if (ndelete > 0)
5092 179 : defaults = list_delete_first_n(defaults, ndelete);
5093 :
5094 : /* And form the combined argument list, not modifying the input list */
5095 5495 : return list_concat_copy(args, defaults);
5096 : }
5097 :
5098 : /*
5099 : * fetch_function_defaults: get function's default arguments as expression list
5100 : */
5101 : static List *
5102 9891 : fetch_function_defaults(HeapTuple func_tuple)
5103 : {
5104 : List *defaults;
5105 : Datum proargdefaults;
5106 : char *str;
5107 :
5108 9891 : proargdefaults = SysCacheGetAttrNotNull(PROCOID, func_tuple,
5109 : Anum_pg_proc_proargdefaults);
5110 9891 : str = TextDatumGetCString(proargdefaults);
5111 9891 : defaults = castNode(List, stringToNode(str));
5112 9891 : pfree(str);
5113 9891 : return defaults;
5114 : }
5115 :
5116 : /*
5117 : * recheck_cast_function_args: recheck function args and typecast as needed
5118 : * after adding defaults.
5119 : *
5120 : * It is possible for some of the defaulted arguments to be polymorphic;
5121 : * therefore we can't assume that the default expressions have the correct
5122 : * data types already. We have to re-resolve polymorphics and do coercion
5123 : * just like the parser did.
5124 : *
5125 : * This should be a no-op if there are no polymorphic arguments,
5126 : * but we do it anyway to be sure.
5127 : *
5128 : * Note: if any casts are needed, the args list is modified in-place;
5129 : * caller should have already copied the list structure.
5130 : */
5131 : static void
5132 14802 : recheck_cast_function_args(List *args, Oid result_type,
5133 : Oid *proargtypes, int pronargs,
5134 : HeapTuple func_tuple)
5135 : {
5136 14802 : Form_pg_proc funcform = (Form_pg_proc) GETSTRUCT(func_tuple);
5137 : int nargs;
5138 : Oid actual_arg_types[FUNC_MAX_ARGS];
5139 : Oid declared_arg_types[FUNC_MAX_ARGS];
5140 : Oid rettype;
5141 : ListCell *lc;
5142 :
5143 14802 : if (list_length(args) > FUNC_MAX_ARGS)
5144 0 : elog(ERROR, "too many function arguments");
5145 14802 : nargs = 0;
5146 72409 : foreach(lc, args)
5147 : {
5148 57607 : actual_arg_types[nargs++] = exprType((Node *) lfirst(lc));
5149 : }
5150 : Assert(nargs == pronargs);
5151 14802 : memcpy(declared_arg_types, proargtypes, pronargs * sizeof(Oid));
5152 14802 : rettype = enforce_generic_type_consistency(actual_arg_types,
5153 : declared_arg_types,
5154 : nargs,
5155 : funcform->prorettype,
5156 : false);
5157 : /* let's just check we got the same answer as the parser did ... */
5158 14802 : if (rettype != result_type)
5159 0 : elog(ERROR, "function's resolved result type changed during planning");
5160 :
5161 : /* perform any necessary typecasting of arguments */
5162 14802 : make_fn_arguments(NULL, args, actual_arg_types, declared_arg_types);
5163 14802 : }
5164 :
5165 : /*
5166 : * evaluate_function: try to pre-evaluate a function call
5167 : *
5168 : * We can do this if the function is strict and has any constant-null inputs
5169 : * (just return a null constant), or if the function is immutable and has all
5170 : * constant inputs (call it and return the result as a Const node). In
5171 : * estimation mode we are willing to pre-evaluate stable functions too.
5172 : *
5173 : * Returns a simplified expression if successful, or NULL if cannot
5174 : * simplify the function.
5175 : */
5176 : static Expr *
5177 963329 : evaluate_function(Oid funcid, Oid result_type, int32 result_typmod,
5178 : Oid result_collid, Oid input_collid, List *args,
5179 : bool funcvariadic,
5180 : HeapTuple func_tuple,
5181 : eval_const_expressions_context *context)
5182 : {
5183 963329 : Form_pg_proc funcform = (Form_pg_proc) GETSTRUCT(func_tuple);
5184 963329 : bool has_nonconst_input = false;
5185 963329 : bool has_null_input = false;
5186 : ListCell *arg;
5187 : FuncExpr *newexpr;
5188 :
5189 : /*
5190 : * Can't simplify if it returns a set.
5191 : */
5192 963329 : if (funcform->proretset)
5193 45763 : return NULL;
5194 :
5195 : /*
5196 : * Can't simplify if it returns RECORD. The immediate problem is that it
5197 : * will be needing an expected tupdesc which we can't supply here.
5198 : *
5199 : * In the case where it has OUT parameters, we could build an expected
5200 : * tupdesc from those, but there may be other gotchas lurking. In
5201 : * particular, if the function were to return NULL, we would produce a
5202 : * null constant with no remaining indication of which concrete record
5203 : * type it is. For now, seems best to leave the function call unreduced.
5204 : */
5205 917566 : if (funcform->prorettype == RECORDOID)
5206 3873 : return NULL;
5207 :
5208 : /*
5209 : * Check for constant inputs and especially constant-NULL inputs.
5210 : */
5211 2546001 : foreach(arg, args)
5212 : {
5213 1632308 : if (IsA(lfirst(arg), Const))
5214 724143 : has_null_input |= ((Const *) lfirst(arg))->constisnull;
5215 : else
5216 908165 : has_nonconst_input = true;
5217 : }
5218 :
5219 : /*
5220 : * If the function is strict and has a constant-NULL input, it will never
5221 : * be called at all, so we can replace the call by a NULL constant, even
5222 : * if there are other inputs that aren't constant, and even if the
5223 : * function is not otherwise immutable.
5224 : */
5225 913693 : if (funcform->proisstrict && has_null_input)
5226 4422 : return (Expr *) makeNullConst(result_type, result_typmod,
5227 : result_collid);
5228 :
5229 : /*
5230 : * Otherwise, can simplify only if all inputs are constants. (For a
5231 : * non-strict function, constant NULL inputs are treated the same as
5232 : * constant non-NULL inputs.)
5233 : */
5234 909271 : if (has_nonconst_input)
5235 691612 : return NULL;
5236 :
5237 : /*
5238 : * Ordinarily we are only allowed to simplify immutable functions. But for
5239 : * purposes of estimation, we consider it okay to simplify functions that
5240 : * are merely stable; the risk that the result might change from planning
5241 : * time to execution time is worth taking in preference to not being able
5242 : * to estimate the value at all.
5243 : */
5244 217659 : if (funcform->provolatile == PROVOLATILE_IMMUTABLE)
5245 : /* okay */ ;
5246 89134 : else if (context->estimate && funcform->provolatile == PROVOLATILE_STABLE)
5247 : /* okay */ ;
5248 : else
5249 87251 : return NULL;
5250 :
5251 : /*
5252 : * OK, looks like we can simplify this operator/function.
5253 : *
5254 : * Build a new FuncExpr node containing the already-simplified arguments.
5255 : */
5256 130408 : newexpr = makeNode(FuncExpr);
5257 130408 : newexpr->funcid = funcid;
5258 130408 : newexpr->funcresulttype = result_type;
5259 130408 : newexpr->funcretset = false;
5260 130408 : newexpr->funcvariadic = funcvariadic;
5261 130408 : newexpr->funcformat = COERCE_EXPLICIT_CALL; /* doesn't matter */
5262 130408 : newexpr->funccollid = result_collid; /* doesn't matter */
5263 130408 : newexpr->inputcollid = input_collid;
5264 130408 : newexpr->args = args;
5265 130408 : newexpr->location = -1;
5266 :
5267 130408 : return evaluate_expr((Expr *) newexpr, result_type, result_typmod,
5268 : result_collid);
5269 : }
5270 :
5271 : /*
5272 : * inline_function: try to expand a function call inline
5273 : *
5274 : * If the function is a sufficiently simple SQL-language function
5275 : * (just "SELECT expression"), then we can inline it and avoid the rather
5276 : * high per-call overhead of SQL functions. Furthermore, this can expose
5277 : * opportunities for constant-folding within the function expression.
5278 : *
5279 : * We have to beware of some special cases however. A directly or
5280 : * indirectly recursive function would cause us to recurse forever,
5281 : * so we keep track of which functions we are already expanding and
5282 : * do not re-expand them. Also, if a parameter is used more than once
5283 : * in the SQL-function body, we require it not to contain any volatile
5284 : * functions (volatiles might deliver inconsistent answers) nor to be
5285 : * unreasonably expensive to evaluate. The expensiveness check not only
5286 : * prevents us from doing multiple evaluations of an expensive parameter
5287 : * at runtime, but is a safety value to limit growth of an expression due
5288 : * to repeated inlining.
5289 : *
5290 : * We must also beware of changing the volatility or strictness status of
5291 : * functions by inlining them.
5292 : *
5293 : * Also, at the moment we can't inline functions returning RECORD. This
5294 : * doesn't work in the general case because it discards information such
5295 : * as OUT-parameter declarations.
5296 : *
5297 : * Also, context-dependent expression nodes in the argument list are trouble.
5298 : *
5299 : * Returns a simplified expression if successful, or NULL if cannot
5300 : * simplify the function.
5301 : */
5302 : static Expr *
5303 828400 : inline_function(Oid funcid, Oid result_type, Oid result_collid,
5304 : Oid input_collid, List *args,
5305 : bool funcvariadic,
5306 : HeapTuple func_tuple,
5307 : eval_const_expressions_context *context)
5308 : {
5309 828400 : Form_pg_proc funcform = (Form_pg_proc) GETSTRUCT(func_tuple);
5310 : char *src;
5311 : Datum tmp;
5312 : bool isNull;
5313 : MemoryContext oldcxt;
5314 : MemoryContext mycxt;
5315 : inline_error_callback_arg callback_arg;
5316 : ErrorContextCallback sqlerrcontext;
5317 : FuncExpr *fexpr;
5318 : SQLFunctionParseInfoPtr pinfo;
5319 : TupleDesc rettupdesc;
5320 : ParseState *pstate;
5321 : List *raw_parsetree_list;
5322 : List *querytree_list;
5323 : Query *querytree;
5324 : Node *newexpr;
5325 : int *usecounts;
5326 : ListCell *arg;
5327 : int i;
5328 :
5329 : /*
5330 : * Forget it if the function is not SQL-language or has other showstopper
5331 : * properties. (The prokind and nargs checks are just paranoia.)
5332 : */
5333 828400 : if (funcform->prolang != SQLlanguageId ||
5334 7487 : funcform->prokind != PROKIND_FUNCTION ||
5335 7487 : funcform->prosecdef ||
5336 7477 : funcform->proretset ||
5337 6044 : funcform->prorettype == RECORDOID ||
5338 11543 : !heap_attisnull(func_tuple, Anum_pg_proc_proconfig, NULL) ||
5339 5754 : funcform->pronargs != list_length(args))
5340 822646 : return NULL;
5341 :
5342 : /* Check for recursive function, and give up trying to expand if so */
5343 5754 : if (list_member_oid(context->active_fns, funcid))
5344 10 : return NULL;
5345 :
5346 : /* Check permission to call function (fail later, if not) */
5347 5744 : if (object_aclcheck(ProcedureRelationId, funcid, GetUserId(), ACL_EXECUTE) != ACLCHECK_OK)
5348 13 : return NULL;
5349 :
5350 : /* Check whether a plugin wants to hook function entry/exit */
5351 5731 : if (FmgrHookIsNeeded(funcid))
5352 0 : return NULL;
5353 :
5354 : /*
5355 : * Make a temporary memory context, so that we don't leak all the stuff
5356 : * that parsing might create.
5357 : */
5358 5731 : mycxt = AllocSetContextCreate(CurrentMemoryContext,
5359 : "inline_function",
5360 : ALLOCSET_DEFAULT_SIZES);
5361 5731 : oldcxt = MemoryContextSwitchTo(mycxt);
5362 :
5363 : /*
5364 : * We need a dummy FuncExpr node containing the already-simplified
5365 : * arguments. (In some cases we don't really need it, but building it is
5366 : * cheap enough that it's not worth contortions to avoid.)
5367 : */
5368 5731 : fexpr = makeNode(FuncExpr);
5369 5731 : fexpr->funcid = funcid;
5370 5731 : fexpr->funcresulttype = result_type;
5371 5731 : fexpr->funcretset = false;
5372 5731 : fexpr->funcvariadic = funcvariadic;
5373 5731 : fexpr->funcformat = COERCE_EXPLICIT_CALL; /* doesn't matter */
5374 5731 : fexpr->funccollid = result_collid; /* doesn't matter */
5375 5731 : fexpr->inputcollid = input_collid;
5376 5731 : fexpr->args = args;
5377 5731 : fexpr->location = -1;
5378 :
5379 : /* Fetch the function body */
5380 5731 : tmp = SysCacheGetAttrNotNull(PROCOID, func_tuple, Anum_pg_proc_prosrc);
5381 5731 : src = TextDatumGetCString(tmp);
5382 :
5383 : /*
5384 : * Setup error traceback support for ereport(). This is so that we can
5385 : * finger the function that bad information came from.
5386 : */
5387 5731 : callback_arg.proname = NameStr(funcform->proname);
5388 5731 : callback_arg.prosrc = src;
5389 :
5390 5731 : sqlerrcontext.callback = sql_inline_error_callback;
5391 5731 : sqlerrcontext.arg = &callback_arg;
5392 5731 : sqlerrcontext.previous = error_context_stack;
5393 5731 : error_context_stack = &sqlerrcontext;
5394 :
5395 : /* If we have prosqlbody, pay attention to that not prosrc */
5396 5731 : tmp = SysCacheGetAttr(PROCOID,
5397 : func_tuple,
5398 : Anum_pg_proc_prosqlbody,
5399 : &isNull);
5400 5731 : if (!isNull)
5401 : {
5402 : Node *n;
5403 : List *query_list;
5404 :
5405 3297 : n = stringToNode(TextDatumGetCString(tmp));
5406 3297 : if (IsA(n, List))
5407 2652 : query_list = linitial_node(List, castNode(List, n));
5408 : else
5409 645 : query_list = list_make1(n);
5410 3297 : if (list_length(query_list) != 1)
5411 5 : goto fail;
5412 3292 : querytree = linitial(query_list);
5413 :
5414 : /*
5415 : * Because we'll insist below that the querytree have an empty rtable
5416 : * and no sublinks, it cannot have any relation references that need
5417 : * to be locked or rewritten. So we can omit those steps.
5418 : */
5419 : }
5420 : else
5421 : {
5422 : /* Set up to handle parameters while parsing the function body. */
5423 2434 : pinfo = prepare_sql_fn_parse_info(func_tuple,
5424 : (Node *) fexpr,
5425 : input_collid);
5426 :
5427 : /*
5428 : * We just do parsing and parse analysis, not rewriting, because
5429 : * rewriting will not affect table-free-SELECT-only queries, which is
5430 : * all that we care about. Also, we can punt as soon as we detect
5431 : * more than one command in the function body.
5432 : */
5433 2434 : raw_parsetree_list = pg_parse_query(src);
5434 2434 : if (list_length(raw_parsetree_list) != 1)
5435 45 : goto fail;
5436 :
5437 2389 : pstate = make_parsestate(NULL);
5438 2389 : pstate->p_sourcetext = src;
5439 2389 : sql_fn_parser_setup(pstate, pinfo);
5440 :
5441 2389 : querytree = transformTopLevelStmt(pstate, linitial(raw_parsetree_list));
5442 :
5443 2385 : free_parsestate(pstate);
5444 : }
5445 :
5446 : /*
5447 : * The single command must be a simple "SELECT expression".
5448 : *
5449 : * Note: if you change the tests involved in this, see also plpgsql's
5450 : * exec_simple_check_plan(). That generally needs to have the same idea
5451 : * of what's a "simple expression", so that inlining a function that
5452 : * previously wasn't inlined won't change plpgsql's conclusion.
5453 : */
5454 5677 : if (!IsA(querytree, Query) ||
5455 5677 : querytree->commandType != CMD_SELECT ||
5456 5576 : querytree->hasAggs ||
5457 5421 : querytree->hasWindowFuncs ||
5458 5421 : querytree->hasTargetSRFs ||
5459 5421 : querytree->hasSubLinks ||
5460 4280 : querytree->cteList ||
5461 4280 : querytree->rtable ||
5462 2718 : querytree->jointree->fromlist ||
5463 2718 : querytree->jointree->quals ||
5464 2718 : querytree->groupClause ||
5465 2718 : querytree->groupingSets ||
5466 2718 : querytree->havingQual ||
5467 2718 : querytree->windowClause ||
5468 2718 : querytree->distinctClause ||
5469 2718 : querytree->sortClause ||
5470 2718 : querytree->limitOffset ||
5471 2718 : querytree->limitCount ||
5472 5320 : querytree->setOperations ||
5473 2660 : list_length(querytree->targetList) != 1)
5474 3067 : goto fail;
5475 :
5476 : /* If the function result is composite, resolve it */
5477 2610 : (void) get_expr_result_type((Node *) fexpr,
5478 : NULL,
5479 : &rettupdesc);
5480 :
5481 : /*
5482 : * Make sure the function (still) returns what it's declared to. This
5483 : * will raise an error if wrong, but that's okay since the function would
5484 : * fail at runtime anyway. Note that check_sql_fn_retval will also insert
5485 : * a coercion if needed to make the tlist expression match the declared
5486 : * type of the function.
5487 : *
5488 : * Note: we do not try this until we have verified that no rewriting was
5489 : * needed; that's probably not important, but let's be careful.
5490 : */
5491 2610 : querytree_list = list_make1(querytree);
5492 2610 : if (check_sql_fn_retval(list_make1(querytree_list),
5493 : result_type, rettupdesc,
5494 2610 : funcform->prokind,
5495 : false))
5496 10 : goto fail; /* reject whole-tuple-result cases */
5497 :
5498 : /*
5499 : * Given the tests above, check_sql_fn_retval shouldn't have decided to
5500 : * inject a projection step, but let's just make sure.
5501 : */
5502 2596 : if (querytree != linitial(querytree_list))
5503 0 : goto fail;
5504 :
5505 : /* Now we can grab the tlist expression */
5506 2596 : newexpr = (Node *) ((TargetEntry *) linitial(querytree->targetList))->expr;
5507 :
5508 : /*
5509 : * If the SQL function returns VOID, we can only inline it if it is a
5510 : * SELECT of an expression returning VOID (ie, it's just a redirection to
5511 : * another VOID-returning function). In all non-VOID-returning cases,
5512 : * check_sql_fn_retval should ensure that newexpr returns the function's
5513 : * declared result type, so this test shouldn't fail otherwise; but we may
5514 : * as well cope gracefully if it does.
5515 : */
5516 2596 : if (exprType(newexpr) != result_type)
5517 15 : goto fail;
5518 :
5519 : /*
5520 : * Additional validity checks on the expression. It mustn't be more
5521 : * volatile than the surrounding function (this is to avoid breaking hacks
5522 : * that involve pretending a function is immutable when it really ain't).
5523 : * If the surrounding function is declared strict, then the expression
5524 : * must contain only strict constructs and must use all of the function
5525 : * parameters (this is overkill, but an exact analysis is hard).
5526 : */
5527 3139 : if (funcform->provolatile == PROVOLATILE_IMMUTABLE &&
5528 558 : contain_mutable_functions(newexpr))
5529 9 : goto fail;
5530 3347 : else if (funcform->provolatile == PROVOLATILE_STABLE &&
5531 775 : contain_volatile_functions(newexpr))
5532 0 : goto fail;
5533 :
5534 3900 : if (funcform->proisstrict &&
5535 1328 : contain_nonstrict_functions(newexpr))
5536 37 : goto fail;
5537 :
5538 : /*
5539 : * If any parameter expression contains a context-dependent node, we can't
5540 : * inline, for fear of putting such a node into the wrong context.
5541 : */
5542 2535 : if (contain_context_dependent_node((Node *) args))
5543 5 : goto fail;
5544 :
5545 : /*
5546 : * We may be able to do it; there are still checks on parameter usage to
5547 : * make, but those are most easily done in combination with the actual
5548 : * substitution of the inputs. So start building expression with inputs
5549 : * substituted.
5550 : */
5551 2530 : usecounts = (int *) palloc0(funcform->pronargs * sizeof(int));
5552 2530 : newexpr = substitute_actual_parameters(newexpr, funcform->pronargs,
5553 : args, usecounts);
5554 :
5555 : /* Now check for parameter usage */
5556 2530 : i = 0;
5557 6757 : foreach(arg, args)
5558 : {
5559 4227 : Node *param = lfirst(arg);
5560 :
5561 4227 : if (usecounts[i] == 0)
5562 : {
5563 : /* Param not used at all: uncool if func is strict */
5564 211 : if (funcform->proisstrict)
5565 0 : goto fail;
5566 : }
5567 4016 : else if (usecounts[i] != 1)
5568 : {
5569 : /* Param used multiple times: uncool if expensive or volatile */
5570 : QualCost eval_cost;
5571 :
5572 : /*
5573 : * We define "expensive" as "contains any subplan or more than 10
5574 : * operators". Note that the subplan search has to be done
5575 : * explicitly, since cost_qual_eval() will barf on unplanned
5576 : * subselects.
5577 : */
5578 281 : if (contain_subplans(param))
5579 0 : goto fail;
5580 281 : cost_qual_eval(&eval_cost, list_make1(param), NULL);
5581 281 : if (eval_cost.startup + eval_cost.per_tuple >
5582 281 : 10 * cpu_operator_cost)
5583 0 : goto fail;
5584 :
5585 : /*
5586 : * Check volatility last since this is more expensive than the
5587 : * above tests
5588 : */
5589 281 : if (contain_volatile_functions(param))
5590 0 : goto fail;
5591 : }
5592 4227 : i++;
5593 : }
5594 :
5595 : /*
5596 : * Whew --- we can make the substitution. Copy the modified expression
5597 : * out of the temporary memory context, and clean up.
5598 : */
5599 2530 : MemoryContextSwitchTo(oldcxt);
5600 :
5601 2530 : newexpr = copyObject(newexpr);
5602 :
5603 2530 : MemoryContextDelete(mycxt);
5604 :
5605 : /*
5606 : * If the result is of a collatable type, force the result to expose the
5607 : * correct collation. In most cases this does not matter, but it's
5608 : * possible that the function result is used directly as a sort key or in
5609 : * other places where we expect exprCollation() to tell the truth.
5610 : */
5611 2530 : if (OidIsValid(result_collid))
5612 : {
5613 1172 : Oid exprcoll = exprCollation(newexpr);
5614 :
5615 1172 : if (OidIsValid(exprcoll) && exprcoll != result_collid)
5616 : {
5617 18 : CollateExpr *newnode = makeNode(CollateExpr);
5618 :
5619 18 : newnode->arg = (Expr *) newexpr;
5620 18 : newnode->collOid = result_collid;
5621 18 : newnode->location = -1;
5622 :
5623 18 : newexpr = (Node *) newnode;
5624 : }
5625 : }
5626 :
5627 : /*
5628 : * Since there is now no trace of the function in the plan tree, we must
5629 : * explicitly record the plan's dependency on the function.
5630 : */
5631 2530 : if (context->root)
5632 2377 : record_plan_function_dependency(context->root, funcid);
5633 :
5634 : /*
5635 : * Recursively try to simplify the modified expression. Here we must add
5636 : * the current function to the context list of active functions.
5637 : */
5638 2530 : context->active_fns = lappend_oid(context->active_fns, funcid);
5639 2530 : newexpr = eval_const_expressions_mutator(newexpr, context);
5640 2529 : context->active_fns = list_delete_last(context->active_fns);
5641 :
5642 2529 : error_context_stack = sqlerrcontext.previous;
5643 :
5644 2529 : return (Expr *) newexpr;
5645 :
5646 : /* Here if func is not inlinable: release temp memory and return NULL */
5647 3193 : fail:
5648 3193 : MemoryContextSwitchTo(oldcxt);
5649 3193 : MemoryContextDelete(mycxt);
5650 3193 : error_context_stack = sqlerrcontext.previous;
5651 :
5652 3193 : return NULL;
5653 : }
5654 :
5655 : /*
5656 : * Replace Param nodes by appropriate actual parameters
5657 : */
5658 : static Node *
5659 2530 : substitute_actual_parameters(Node *expr, int nargs, List *args,
5660 : int *usecounts)
5661 : {
5662 : substitute_actual_parameters_context context;
5663 :
5664 2530 : context.nargs = nargs;
5665 2530 : context.args = args;
5666 2530 : context.usecounts = usecounts;
5667 :
5668 2530 : return substitute_actual_parameters_mutator(expr, &context);
5669 : }
5670 :
5671 : static Node *
5672 14266 : substitute_actual_parameters_mutator(Node *node,
5673 : substitute_actual_parameters_context *context)
5674 : {
5675 14266 : if (node == NULL)
5676 399 : return NULL;
5677 13867 : if (IsA(node, Param))
5678 : {
5679 4315 : Param *param = (Param *) node;
5680 :
5681 4315 : if (param->paramkind != PARAM_EXTERN)
5682 0 : elog(ERROR, "unexpected paramkind: %d", (int) param->paramkind);
5683 4315 : if (param->paramid <= 0 || param->paramid > context->nargs)
5684 0 : elog(ERROR, "invalid paramid: %d", param->paramid);
5685 :
5686 : /* Count usage of parameter */
5687 4315 : context->usecounts[param->paramid - 1]++;
5688 :
5689 : /* Select the appropriate actual arg and replace the Param with it */
5690 : /* We don't need to copy at this time (it'll get done later) */
5691 4315 : return list_nth(context->args, param->paramid - 1);
5692 : }
5693 9552 : return expression_tree_mutator(node, substitute_actual_parameters_mutator, context);
5694 : }
5695 :
5696 : /*
5697 : * error context callback to let us supply a call-stack traceback
5698 : */
5699 : static void
5700 13 : sql_inline_error_callback(void *arg)
5701 : {
5702 13 : inline_error_callback_arg *callback_arg = (inline_error_callback_arg *) arg;
5703 : int syntaxerrposition;
5704 :
5705 : /* If it's a syntax error, convert to internal syntax error report */
5706 13 : syntaxerrposition = geterrposition();
5707 13 : if (syntaxerrposition > 0)
5708 : {
5709 4 : errposition(0);
5710 4 : internalerrposition(syntaxerrposition);
5711 4 : internalerrquery(callback_arg->prosrc);
5712 : }
5713 :
5714 13 : errcontext("SQL function \"%s\" during inlining", callback_arg->proname);
5715 13 : }
5716 :
5717 : /*
5718 : * evaluate_expr: pre-evaluate a constant expression
5719 : *
5720 : * We use the executor's routine ExecEvalExpr() to avoid duplication of
5721 : * code and ensure we get the same result as the executor would get.
5722 : */
5723 : Expr *
5724 157126 : evaluate_expr(Expr *expr, Oid result_type, int32 result_typmod,
5725 : Oid result_collation)
5726 : {
5727 : EState *estate;
5728 : ExprState *exprstate;
5729 : MemoryContext oldcontext;
5730 : Datum const_val;
5731 : bool const_is_null;
5732 : int16 resultTypLen;
5733 : bool resultTypByVal;
5734 :
5735 : /*
5736 : * To use the executor, we need an EState.
5737 : */
5738 157126 : estate = CreateExecutorState();
5739 :
5740 : /* We can use the estate's working context to avoid memory leaks. */
5741 157126 : oldcontext = MemoryContextSwitchTo(estate->es_query_cxt);
5742 :
5743 : /* Make sure any opfuncids are filled in. */
5744 157126 : fix_opfuncids((Node *) expr);
5745 :
5746 : /*
5747 : * Prepare expr for execution. (Note: we can't use ExecPrepareExpr
5748 : * because it'd result in recursively invoking eval_const_expressions.)
5749 : */
5750 157126 : exprstate = ExecInitExpr(expr, NULL);
5751 :
5752 : /*
5753 : * And evaluate it.
5754 : *
5755 : * It is OK to use a default econtext because none of the ExecEvalExpr()
5756 : * code used in this situation will use econtext. That might seem
5757 : * fortuitous, but it's not so unreasonable --- a constant expression does
5758 : * not depend on context, by definition, n'est ce pas?
5759 : */
5760 157110 : const_val = ExecEvalExprSwitchContext(exprstate,
5761 157110 : GetPerTupleExprContext(estate),
5762 : &const_is_null);
5763 :
5764 : /* Get info needed about result datatype */
5765 154477 : get_typlenbyval(result_type, &resultTypLen, &resultTypByVal);
5766 :
5767 : /* Get back to outer memory context */
5768 154477 : MemoryContextSwitchTo(oldcontext);
5769 :
5770 : /*
5771 : * Must copy result out of sub-context used by expression eval.
5772 : *
5773 : * Also, if it's varlena, forcibly detoast it. This protects us against
5774 : * storing TOAST pointers into plans that might outlive the referenced
5775 : * data. (makeConst would handle detoasting anyway, but it's worth a few
5776 : * extra lines here so that we can do the copy and detoast in one step.)
5777 : */
5778 154477 : if (!const_is_null)
5779 : {
5780 149502 : if (resultTypLen == -1)
5781 70304 : const_val = PointerGetDatum(PG_DETOAST_DATUM_COPY(const_val));
5782 : else
5783 79198 : const_val = datumCopy(const_val, resultTypByVal, resultTypLen);
5784 : }
5785 :
5786 : /* Release all the junk we just created */
5787 154477 : FreeExecutorState(estate);
5788 :
5789 : /*
5790 : * Make the constant result node.
5791 : */
5792 154477 : return (Expr *) makeConst(result_type, result_typmod, result_collation,
5793 : resultTypLen,
5794 : const_val, const_is_null,
5795 : resultTypByVal);
5796 : }
5797 :
5798 :
5799 : /*
5800 : * inline_function_in_from
5801 : * Attempt to "inline" a function in the FROM clause.
5802 : *
5803 : * "rte" is an RTE_FUNCTION rangetable entry. If it represents a call of a
5804 : * function that can be inlined, expand the function and return the
5805 : * substitute Query structure. Otherwise, return NULL.
5806 : *
5807 : * We assume that the RTE's expression has already been put through
5808 : * eval_const_expressions(), which among other things will take care of
5809 : * default arguments and named-argument notation.
5810 : *
5811 : * This has a good deal of similarity to inline_function(), but that's
5812 : * for the general-expression case, and there are enough differences to
5813 : * justify separate functions.
5814 : */
5815 : Query *
5816 35956 : inline_function_in_from(PlannerInfo *root, RangeTblEntry *rte)
5817 : {
5818 : RangeTblFunction *rtfunc;
5819 : FuncExpr *fexpr;
5820 : Oid func_oid;
5821 : HeapTuple func_tuple;
5822 : Form_pg_proc funcform;
5823 : MemoryContext oldcxt;
5824 : MemoryContext mycxt;
5825 : Datum tmp;
5826 : char *src;
5827 : inline_error_callback_arg callback_arg;
5828 : ErrorContextCallback sqlerrcontext;
5829 35956 : Query *querytree = NULL;
5830 :
5831 : Assert(rte->rtekind == RTE_FUNCTION);
5832 :
5833 : /*
5834 : * Guard against infinite recursion during expansion by checking for stack
5835 : * overflow. (There's no need to do more.)
5836 : */
5837 35956 : check_stack_depth();
5838 :
5839 : /* Fail if the RTE has ORDINALITY - we don't implement that here. */
5840 35956 : if (rte->funcordinality)
5841 774 : return NULL;
5842 :
5843 : /* Fail if RTE isn't a single, simple FuncExpr */
5844 35182 : if (list_length(rte->functions) != 1)
5845 57 : return NULL;
5846 35125 : rtfunc = (RangeTblFunction *) linitial(rte->functions);
5847 :
5848 35125 : if (!IsA(rtfunc->funcexpr, FuncExpr))
5849 345 : return NULL;
5850 34780 : fexpr = (FuncExpr *) rtfunc->funcexpr;
5851 :
5852 34780 : func_oid = fexpr->funcid;
5853 :
5854 : /*
5855 : * Refuse to inline if the arguments contain any volatile functions or
5856 : * sub-selects. Volatile functions are rejected because inlining may
5857 : * result in the arguments being evaluated multiple times, risking a
5858 : * change in behavior. Sub-selects are rejected partly for implementation
5859 : * reasons (pushing them down another level might change their behavior)
5860 : * and partly because they're likely to be expensive and so multiple
5861 : * evaluation would be bad.
5862 : */
5863 69442 : if (contain_volatile_functions((Node *) fexpr->args) ||
5864 34662 : contain_subplans((Node *) fexpr->args))
5865 283 : return NULL;
5866 :
5867 : /* Check permission to call function (fail later, if not) */
5868 34497 : if (object_aclcheck(ProcedureRelationId, func_oid, GetUserId(), ACL_EXECUTE) != ACLCHECK_OK)
5869 6 : return NULL;
5870 :
5871 : /* Check whether a plugin wants to hook function entry/exit */
5872 34491 : if (FmgrHookIsNeeded(func_oid))
5873 0 : return NULL;
5874 :
5875 : /*
5876 : * OK, let's take a look at the function's pg_proc entry.
5877 : */
5878 34491 : func_tuple = SearchSysCache1(PROCOID, ObjectIdGetDatum(func_oid));
5879 34491 : if (!HeapTupleIsValid(func_tuple))
5880 0 : elog(ERROR, "cache lookup failed for function %u", func_oid);
5881 34491 : funcform = (Form_pg_proc) GETSTRUCT(func_tuple);
5882 :
5883 : /*
5884 : * If the function SETs any configuration parameters, inlining would cause
5885 : * us to miss making those changes.
5886 : */
5887 34491 : if (!heap_attisnull(func_tuple, Anum_pg_proc_proconfig, NULL))
5888 : {
5889 8 : ReleaseSysCache(func_tuple);
5890 8 : return NULL;
5891 : }
5892 :
5893 : /*
5894 : * Make a temporary memory context, so that we don't leak all the stuff
5895 : * that parsing and rewriting might create. If we succeed, we'll copy
5896 : * just the finished query tree back up to the caller's context.
5897 : */
5898 34483 : mycxt = AllocSetContextCreate(CurrentMemoryContext,
5899 : "inline_function_in_from",
5900 : ALLOCSET_DEFAULT_SIZES);
5901 34483 : oldcxt = MemoryContextSwitchTo(mycxt);
5902 :
5903 : /* Fetch the function body */
5904 34483 : tmp = SysCacheGetAttrNotNull(PROCOID, func_tuple, Anum_pg_proc_prosrc);
5905 34483 : src = TextDatumGetCString(tmp);
5906 :
5907 : /*
5908 : * If the function has an attached support function that can handle
5909 : * SupportRequestInlineInFrom, then attempt to inline with that.
5910 : */
5911 34483 : if (funcform->prosupport)
5912 : {
5913 : SupportRequestInlineInFrom req;
5914 :
5915 12898 : req.type = T_SupportRequestInlineInFrom;
5916 12898 : req.root = root;
5917 12898 : req.rtfunc = rtfunc;
5918 12898 : req.proc = func_tuple;
5919 :
5920 : querytree = (Query *)
5921 12898 : DatumGetPointer(OidFunctionCall1(funcform->prosupport,
5922 : PointerGetDatum(&req)));
5923 : }
5924 :
5925 : /*
5926 : * Setup error traceback support for ereport(). This is so that we can
5927 : * finger the function that bad information came from. We don't install
5928 : * this while running the support function, since it'd be likely to do the
5929 : * wrong thing: any parse errors reported during that are very likely not
5930 : * against the raw function source text.
5931 : */
5932 34483 : callback_arg.proname = NameStr(funcform->proname);
5933 34483 : callback_arg.prosrc = src;
5934 :
5935 34483 : sqlerrcontext.callback = sql_inline_error_callback;
5936 34483 : sqlerrcontext.arg = &callback_arg;
5937 34483 : sqlerrcontext.previous = error_context_stack;
5938 34483 : error_context_stack = &sqlerrcontext;
5939 :
5940 : /*
5941 : * If SupportRequestInlineInFrom didn't work, try our built-in inlining
5942 : * mechanism.
5943 : */
5944 34483 : if (!querytree)
5945 34463 : querytree = inline_sql_function_in_from(root, rtfunc, fexpr,
5946 : func_tuple, funcform, src);
5947 :
5948 34479 : if (!querytree)
5949 34274 : goto fail; /* no luck there either, fail */
5950 :
5951 : /*
5952 : * The result had better be a SELECT Query.
5953 : */
5954 : Assert(IsA(querytree, Query));
5955 : Assert(querytree->commandType == CMD_SELECT);
5956 :
5957 : /*
5958 : * Looks good --- substitute parameters into the query.
5959 : */
5960 205 : querytree = substitute_actual_parameters_in_from(querytree,
5961 205 : funcform->pronargs,
5962 : fexpr->args);
5963 :
5964 : /*
5965 : * Copy the modified query out of the temporary memory context, and clean
5966 : * up.
5967 : */
5968 205 : MemoryContextSwitchTo(oldcxt);
5969 :
5970 205 : querytree = copyObject(querytree);
5971 :
5972 205 : MemoryContextDelete(mycxt);
5973 205 : error_context_stack = sqlerrcontext.previous;
5974 205 : ReleaseSysCache(func_tuple);
5975 :
5976 : /*
5977 : * We don't have to fix collations here because the upper query is already
5978 : * parsed, ie, the collations in the RTE are what count.
5979 : */
5980 :
5981 : /*
5982 : * Since there is now no trace of the function in the plan tree, we must
5983 : * explicitly record the plan's dependency on the function.
5984 : */
5985 205 : record_plan_function_dependency(root, func_oid);
5986 :
5987 : /*
5988 : * We must also notice if the inserted query adds a dependency on the
5989 : * calling role due to RLS quals.
5990 : */
5991 205 : if (querytree->hasRowSecurity)
5992 60 : root->glob->dependsOnRole = true;
5993 :
5994 205 : return querytree;
5995 :
5996 : /* Here if func is not inlinable: release temp memory and return NULL */
5997 34274 : fail:
5998 34274 : MemoryContextSwitchTo(oldcxt);
5999 34274 : MemoryContextDelete(mycxt);
6000 34274 : error_context_stack = sqlerrcontext.previous;
6001 34274 : ReleaseSysCache(func_tuple);
6002 :
6003 34274 : return NULL;
6004 : }
6005 :
6006 : /*
6007 : * inline_sql_function_in_from
6008 : *
6009 : * This implements inline_function_in_from for SQL-language functions.
6010 : * Returns NULL if the function couldn't be inlined.
6011 : *
6012 : * The division of labor between here and inline_function_in_from is based
6013 : * on the rule that inline_function_in_from should make all checks that are
6014 : * certain to be required in both this case and the support-function case.
6015 : * Support functions might also want to make checks analogous to the ones
6016 : * made here, but then again they might not, or they might just assume that
6017 : * the function they are attached to can validly be inlined.
6018 : */
6019 : static Query *
6020 34463 : inline_sql_function_in_from(PlannerInfo *root,
6021 : RangeTblFunction *rtfunc,
6022 : FuncExpr *fexpr,
6023 : HeapTuple func_tuple,
6024 : Form_pg_proc funcform,
6025 : const char *src)
6026 : {
6027 : Datum sqlbody;
6028 : bool isNull;
6029 : List *querytree_list;
6030 : Query *querytree;
6031 : TypeFuncClass functypclass;
6032 : TupleDesc rettupdesc;
6033 :
6034 : /*
6035 : * The function must be declared to return a set, else inlining would
6036 : * change the results if the contained SELECT didn't return exactly one
6037 : * row.
6038 : */
6039 34463 : if (!fexpr->funcretset)
6040 5725 : return NULL;
6041 :
6042 : /*
6043 : * Forget it if the function is not SQL-language or has other showstopper
6044 : * properties. In particular it mustn't be declared STRICT, since we
6045 : * couldn't enforce that. It also mustn't be VOLATILE, because that is
6046 : * supposed to cause it to be executed with its own snapshot, rather than
6047 : * sharing the snapshot of the calling query. We also disallow returning
6048 : * SETOF VOID, because inlining would result in exposing the actual result
6049 : * of the function's last SELECT, which should not happen in that case.
6050 : * (Rechecking prokind, proretset, and pronargs is just paranoia.)
6051 : */
6052 28738 : if (funcform->prolang != SQLlanguageId ||
6053 768 : funcform->prokind != PROKIND_FUNCTION ||
6054 768 : funcform->proisstrict ||
6055 718 : funcform->provolatile == PROVOLATILE_VOLATILE ||
6056 194 : funcform->prorettype == VOIDOID ||
6057 189 : funcform->prosecdef ||
6058 189 : !funcform->proretset ||
6059 189 : list_length(fexpr->args) != funcform->pronargs)
6060 28549 : return NULL;
6061 :
6062 : /* If we have prosqlbody, pay attention to that not prosrc */
6063 189 : sqlbody = SysCacheGetAttr(PROCOID,
6064 : func_tuple,
6065 : Anum_pg_proc_prosqlbody,
6066 : &isNull);
6067 189 : if (!isNull)
6068 : {
6069 : Node *n;
6070 :
6071 10 : n = stringToNode(TextDatumGetCString(sqlbody));
6072 10 : if (IsA(n, List))
6073 10 : querytree_list = linitial_node(List, castNode(List, n));
6074 : else
6075 0 : querytree_list = list_make1(n);
6076 10 : if (list_length(querytree_list) != 1)
6077 0 : return NULL;
6078 10 : querytree = linitial(querytree_list);
6079 :
6080 : /* Acquire necessary locks, then apply rewriter. */
6081 10 : AcquireRewriteLocks(querytree, true, false);
6082 10 : querytree_list = pg_rewrite_query(querytree);
6083 10 : if (list_length(querytree_list) != 1)
6084 0 : return NULL;
6085 10 : querytree = linitial(querytree_list);
6086 : }
6087 : else
6088 : {
6089 : SQLFunctionParseInfoPtr pinfo;
6090 : List *raw_parsetree_list;
6091 :
6092 : /*
6093 : * Set up to handle parameters while parsing the function body. We
6094 : * can use the FuncExpr just created as the input for
6095 : * prepare_sql_fn_parse_info.
6096 : */
6097 179 : pinfo = prepare_sql_fn_parse_info(func_tuple,
6098 : (Node *) fexpr,
6099 : fexpr->inputcollid);
6100 :
6101 : /*
6102 : * Parse, analyze, and rewrite (unlike inline_function(), we can't
6103 : * skip rewriting here). We can fail as soon as we find more than one
6104 : * query, though.
6105 : */
6106 179 : raw_parsetree_list = pg_parse_query(src);
6107 179 : if (list_length(raw_parsetree_list) != 1)
6108 0 : return NULL;
6109 :
6110 179 : querytree_list = pg_analyze_and_rewrite_withcb(linitial(raw_parsetree_list),
6111 : src,
6112 : (ParserSetupHook) sql_fn_parser_setup,
6113 : pinfo, NULL);
6114 179 : if (list_length(querytree_list) != 1)
6115 0 : return NULL;
6116 179 : querytree = linitial(querytree_list);
6117 : }
6118 :
6119 : /*
6120 : * Also resolve the actual function result tupdesc, if composite. If we
6121 : * have a coldeflist, believe that; otherwise use get_expr_result_type.
6122 : * (This logic should match ExecInitFunctionScan.)
6123 : */
6124 189 : if (rtfunc->funccolnames != NIL)
6125 : {
6126 19 : functypclass = TYPEFUNC_RECORD;
6127 19 : rettupdesc = BuildDescFromLists(rtfunc->funccolnames,
6128 19 : rtfunc->funccoltypes,
6129 19 : rtfunc->funccoltypmods,
6130 19 : rtfunc->funccolcollations);
6131 : }
6132 : else
6133 170 : functypclass = get_expr_result_type((Node *) fexpr, NULL, &rettupdesc);
6134 :
6135 : /*
6136 : * The single command must be a plain SELECT.
6137 : */
6138 189 : if (!IsA(querytree, Query) ||
6139 189 : querytree->commandType != CMD_SELECT)
6140 0 : return NULL;
6141 :
6142 : /*
6143 : * Make sure the function (still) returns what it's declared to. This
6144 : * will raise an error if wrong, but that's okay since the function would
6145 : * fail at runtime anyway. Note that check_sql_fn_retval will also insert
6146 : * coercions if needed to make the tlist expression(s) match the declared
6147 : * type of the function. We also ask it to insert dummy NULL columns for
6148 : * any dropped columns in rettupdesc, so that the elements of the modified
6149 : * tlist match up to the attribute numbers.
6150 : *
6151 : * If the function returns a composite type, don't inline unless the check
6152 : * shows it's returning a whole tuple result; otherwise what it's
6153 : * returning is a single composite column which is not what we need.
6154 : */
6155 189 : if (!check_sql_fn_retval(list_make1(querytree_list),
6156 : fexpr->funcresulttype, rettupdesc,
6157 189 : funcform->prokind,
6158 75 : true) &&
6159 75 : (functypclass == TYPEFUNC_COMPOSITE ||
6160 75 : functypclass == TYPEFUNC_COMPOSITE_DOMAIN ||
6161 : functypclass == TYPEFUNC_RECORD))
6162 0 : return NULL; /* reject not-whole-tuple-result cases */
6163 :
6164 : /*
6165 : * check_sql_fn_retval might've inserted a projection step, but that's
6166 : * fine; just make sure we use the upper Query.
6167 : */
6168 185 : querytree = linitial_node(Query, querytree_list);
6169 :
6170 185 : return querytree;
6171 : }
6172 :
6173 : /*
6174 : * Replace Param nodes by appropriate actual parameters
6175 : *
6176 : * This is just enough different from substitute_actual_parameters()
6177 : * that it needs its own code.
6178 : */
6179 : static Query *
6180 205 : substitute_actual_parameters_in_from(Query *expr, int nargs, List *args)
6181 : {
6182 : substitute_actual_parameters_in_from_context context;
6183 :
6184 205 : context.nargs = nargs;
6185 205 : context.args = args;
6186 205 : context.sublevels_up = 1;
6187 :
6188 205 : return query_tree_mutator(expr,
6189 : substitute_actual_parameters_in_from_mutator,
6190 : &context,
6191 : 0);
6192 : }
6193 :
6194 : static Node *
6195 7695 : substitute_actual_parameters_in_from_mutator(Node *node,
6196 : substitute_actual_parameters_in_from_context *context)
6197 : {
6198 : Node *result;
6199 :
6200 7695 : if (node == NULL)
6201 4480 : return NULL;
6202 3215 : if (IsA(node, Query))
6203 : {
6204 125 : context->sublevels_up++;
6205 125 : result = (Node *) query_tree_mutator((Query *) node,
6206 : substitute_actual_parameters_in_from_mutator,
6207 : context,
6208 : 0);
6209 125 : context->sublevels_up--;
6210 125 : return result;
6211 : }
6212 3090 : if (IsA(node, Param))
6213 : {
6214 95 : Param *param = (Param *) node;
6215 :
6216 95 : if (param->paramkind == PARAM_EXTERN)
6217 : {
6218 95 : if (param->paramid <= 0 || param->paramid > context->nargs)
6219 0 : elog(ERROR, "invalid paramid: %d", param->paramid);
6220 :
6221 : /*
6222 : * Since the parameter is being inserted into a subquery, we must
6223 : * adjust levels.
6224 : */
6225 95 : result = copyObject(list_nth(context->args, param->paramid - 1));
6226 95 : IncrementVarSublevelsUp(result, context->sublevels_up, 0);
6227 95 : return result;
6228 : }
6229 : }
6230 2995 : return expression_tree_mutator(node,
6231 : substitute_actual_parameters_in_from_mutator,
6232 : context);
6233 : }
6234 :
6235 : /*
6236 : * pull_paramids
6237 : * Returns a Bitmapset containing the paramids of all Params in 'expr'.
6238 : */
6239 : Bitmapset *
6240 1536 : pull_paramids(Expr *expr)
6241 : {
6242 1536 : Bitmapset *result = NULL;
6243 :
6244 1536 : (void) pull_paramids_walker((Node *) expr, &result);
6245 :
6246 1536 : return result;
6247 : }
6248 :
6249 : static bool
6250 3436 : pull_paramids_walker(Node *node, Bitmapset **context)
6251 : {
6252 3436 : if (node == NULL)
6253 10 : return false;
6254 3426 : if (IsA(node, Param))
6255 : {
6256 1589 : Param *param = (Param *) node;
6257 :
6258 1589 : *context = bms_add_member(*context, param->paramid);
6259 1589 : return false;
6260 : }
6261 1837 : return expression_tree_walker(node, pull_paramids_walker, context);
6262 : }
6263 :
6264 : /*
6265 : * Build ScalarArrayOpExpr on top of 'exprs.' 'haveNonConst' indicates
6266 : * whether at least one of the expressions is not Const. When it's false,
6267 : * the array constant is built directly; otherwise, we have to build a child
6268 : * ArrayExpr. The 'exprs' list gets freed if not directly used in the output
6269 : * expression tree.
6270 : */
6271 : ScalarArrayOpExpr *
6272 2933 : make_SAOP_expr(Oid oper, Node *leftexpr, Oid coltype, Oid arraycollid,
6273 : Oid inputcollid, List *exprs, bool haveNonConst)
6274 : {
6275 2933 : Node *arrayNode = NULL;
6276 2933 : ScalarArrayOpExpr *saopexpr = NULL;
6277 2933 : Oid arraytype = get_array_type(coltype);
6278 :
6279 2933 : if (!OidIsValid(arraytype))
6280 0 : return NULL;
6281 :
6282 : /*
6283 : * Assemble an array from the list of constants. It seems more profitable
6284 : * to build a const array. But in the presence of other nodes, we don't
6285 : * have a specific value here and must employ an ArrayExpr instead.
6286 : */
6287 2933 : if (haveNonConst)
6288 : {
6289 84 : ArrayExpr *arrayExpr = makeNode(ArrayExpr);
6290 :
6291 : /* array_collid will be set by parse_collate.c */
6292 84 : arrayExpr->element_typeid = coltype;
6293 84 : arrayExpr->array_typeid = arraytype;
6294 84 : arrayExpr->multidims = false;
6295 84 : arrayExpr->elements = exprs;
6296 84 : arrayExpr->location = -1;
6297 :
6298 84 : arrayNode = (Node *) arrayExpr;
6299 : }
6300 : else
6301 : {
6302 : int16 typlen;
6303 : bool typbyval;
6304 : char typalign;
6305 : Datum *elems;
6306 : bool *nulls;
6307 2849 : int i = 0;
6308 : ArrayType *arrayConst;
6309 2849 : int dims[1] = {list_length(exprs)};
6310 2849 : int lbs[1] = {1};
6311 :
6312 2849 : get_typlenbyvalalign(coltype, &typlen, &typbyval, &typalign);
6313 :
6314 2849 : elems = palloc_array(Datum, list_length(exprs));
6315 2849 : nulls = palloc_array(bool, list_length(exprs));
6316 11801 : foreach_node(Const, value, exprs)
6317 : {
6318 6103 : elems[i] = value->constvalue;
6319 6103 : nulls[i++] = value->constisnull;
6320 : }
6321 :
6322 2849 : arrayConst = construct_md_array(elems, nulls, 1, dims, lbs,
6323 : coltype, typlen, typbyval, typalign);
6324 2849 : arrayNode = (Node *) makeConst(arraytype, -1, arraycollid,
6325 : -1, PointerGetDatum(arrayConst),
6326 : false, false);
6327 :
6328 2849 : pfree(elems);
6329 2849 : pfree(nulls);
6330 2849 : list_free(exprs);
6331 : }
6332 :
6333 : /* Build the SAOP expression node */
6334 2933 : saopexpr = makeNode(ScalarArrayOpExpr);
6335 2933 : saopexpr->opno = oper;
6336 2933 : saopexpr->opfuncid = get_opcode(oper);
6337 2933 : saopexpr->hashfuncid = InvalidOid;
6338 2933 : saopexpr->negfuncid = InvalidOid;
6339 2933 : saopexpr->useOr = true;
6340 2933 : saopexpr->inputcollid = inputcollid;
6341 2933 : saopexpr->args = list_make2(leftexpr, arrayNode);
6342 2933 : saopexpr->location = -1;
6343 :
6344 2933 : return saopexpr;
6345 : }
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