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 "catalog/pg_class.h"
24 : #include "catalog/pg_inherits.h"
25 : #include "catalog/pg_language.h"
26 : #include "catalog/pg_operator.h"
27 : #include "catalog/pg_proc.h"
28 : #include "catalog/pg_type.h"
29 : #include "executor/executor.h"
30 : #include "executor/functions.h"
31 : #include "funcapi.h"
32 : #include "miscadmin.h"
33 : #include "nodes/makefuncs.h"
34 : #include "nodes/multibitmapset.h"
35 : #include "nodes/nodeFuncs.h"
36 : #include "nodes/subscripting.h"
37 : #include "nodes/supportnodes.h"
38 : #include "optimizer/clauses.h"
39 : #include "optimizer/cost.h"
40 : #include "optimizer/optimizer.h"
41 : #include "optimizer/pathnode.h"
42 : #include "optimizer/plancat.h"
43 : #include "optimizer/planmain.h"
44 : #include "parser/analyze.h"
45 : #include "parser/parse_coerce.h"
46 : #include "parser/parse_collate.h"
47 : #include "parser/parse_func.h"
48 : #include "parser/parse_oper.h"
49 : #include "parser/parsetree.h"
50 : #include "rewrite/rewriteHandler.h"
51 : #include "rewrite/rewriteManip.h"
52 : #include "tcop/tcopprot.h"
53 : #include "utils/acl.h"
54 : #include "utils/builtins.h"
55 : #include "utils/datum.h"
56 : #include "utils/fmgroids.h"
57 : #include "utils/json.h"
58 : #include "utils/jsonb.h"
59 : #include "utils/jsonpath.h"
60 : #include "utils/lsyscache.h"
61 : #include "utils/memutils.h"
62 : #include "utils/syscache.h"
63 : #include "utils/typcache.h"
64 :
65 : typedef struct
66 : {
67 : ParamListInfo boundParams;
68 : PlannerInfo *root;
69 : List *active_fns;
70 : Node *case_val;
71 : bool estimate;
72 : } eval_const_expressions_context;
73 :
74 : typedef struct
75 : {
76 : int nargs;
77 : List *args;
78 : int *usecounts;
79 : } substitute_actual_parameters_context;
80 :
81 : typedef struct
82 : {
83 : int nargs;
84 : List *args;
85 : int sublevels_up;
86 : } substitute_actual_parameters_in_from_context;
87 :
88 : typedef struct
89 : {
90 : char *proname;
91 : char *prosrc;
92 : } inline_error_callback_arg;
93 :
94 : typedef struct
95 : {
96 : char max_hazard; /* worst proparallel hazard found so far */
97 : char max_interesting; /* worst proparallel hazard of interest */
98 : List *safe_param_ids; /* PARAM_EXEC Param IDs to treat as safe */
99 : } max_parallel_hazard_context;
100 :
101 : static bool contain_agg_clause_walker(Node *node, void *context);
102 : static bool find_window_functions_walker(Node *node, WindowFuncLists *lists);
103 : static bool contain_subplans_walker(Node *node, void *context);
104 : static bool contain_mutable_functions_walker(Node *node, void *context);
105 : static bool contain_volatile_functions_walker(Node *node, void *context);
106 : static bool contain_volatile_functions_not_nextval_walker(Node *node, void *context);
107 : static bool max_parallel_hazard_walker(Node *node,
108 : max_parallel_hazard_context *context);
109 : static bool contain_nonstrict_functions_walker(Node *node, void *context);
110 : static bool contain_exec_param_walker(Node *node, List *param_ids);
111 : static bool contain_context_dependent_node(Node *clause);
112 : static bool contain_context_dependent_node_walker(Node *node, int *flags);
113 : static bool contain_leaked_vars_walker(Node *node, void *context);
114 : static Relids find_nonnullable_rels_walker(Node *node, bool top_level);
115 : static List *find_nonnullable_vars_walker(Node *node, bool top_level);
116 : static void find_subquery_safe_quals(Node *jtnode, List **safe_quals);
117 : static bool is_strict_saop(ScalarArrayOpExpr *expr, bool falseOK);
118 : static bool convert_saop_to_hashed_saop_walker(Node *node, void *context);
119 : static Node *eval_const_expressions_mutator(Node *node,
120 : eval_const_expressions_context *context);
121 : static bool contain_non_const_walker(Node *node, void *context);
122 : static bool ece_function_is_safe(Oid funcid,
123 : eval_const_expressions_context *context);
124 : static List *simplify_or_arguments(List *args,
125 : eval_const_expressions_context *context,
126 : bool *haveNull, bool *forceTrue);
127 : static List *simplify_and_arguments(List *args,
128 : eval_const_expressions_context *context,
129 : bool *haveNull, bool *forceFalse);
130 : static Node *simplify_boolean_equality(Oid opno, List *args);
131 : static Expr *simplify_function(Oid funcid,
132 : Oid result_type, int32 result_typmod,
133 : Oid result_collid, Oid input_collid, List **args_p,
134 : bool funcvariadic, bool process_args, bool allow_non_const,
135 : eval_const_expressions_context *context);
136 : static Node *simplify_aggref(Aggref *aggref,
137 : eval_const_expressions_context *context);
138 : static List *reorder_function_arguments(List *args, int pronargs,
139 : HeapTuple func_tuple);
140 : static List *add_function_defaults(List *args, int pronargs,
141 : HeapTuple func_tuple);
142 : static List *fetch_function_defaults(HeapTuple func_tuple);
143 : static void recheck_cast_function_args(List *args, Oid result_type,
144 : Oid *proargtypes, int pronargs,
145 : HeapTuple func_tuple);
146 : static Expr *evaluate_function(Oid funcid, Oid result_type, int32 result_typmod,
147 : Oid result_collid, Oid input_collid, List *args,
148 : bool funcvariadic,
149 : HeapTuple func_tuple,
150 : eval_const_expressions_context *context);
151 : static Expr *inline_function(Oid funcid, Oid result_type, Oid result_collid,
152 : Oid input_collid, List *args,
153 : bool funcvariadic,
154 : HeapTuple func_tuple,
155 : eval_const_expressions_context *context);
156 : static Node *substitute_actual_parameters(Node *expr, int nargs, List *args,
157 : int *usecounts);
158 : static Node *substitute_actual_parameters_mutator(Node *node,
159 : substitute_actual_parameters_context *context);
160 : static void sql_inline_error_callback(void *arg);
161 : static Query *inline_sql_function_in_from(PlannerInfo *root,
162 : RangeTblFunction *rtfunc,
163 : FuncExpr *fexpr,
164 : HeapTuple func_tuple,
165 : Form_pg_proc funcform,
166 : const char *src);
167 : static Query *substitute_actual_parameters_in_from(Query *expr,
168 : int nargs, List *args);
169 : static Node *substitute_actual_parameters_in_from_mutator(Node *node,
170 : substitute_actual_parameters_in_from_context *context);
171 : static bool pull_paramids_walker(Node *node, Bitmapset **context);
172 :
173 :
174 : /*****************************************************************************
175 : * Aggregate-function clause manipulation
176 : *****************************************************************************/
177 :
178 : /*
179 : * contain_agg_clause
180 : * Recursively search for Aggref/GroupingFunc nodes within a clause.
181 : *
182 : * Returns true if any aggregate found.
183 : *
184 : * This does not descend into subqueries, and so should be used only after
185 : * reduction of sublinks to subplans, or in contexts where it's known there
186 : * are no subqueries. There mustn't be outer-aggregate references either.
187 : *
188 : * (If you want something like this but able to deal with subqueries,
189 : * see rewriteManip.c's contain_aggs_of_level().)
190 : */
191 : bool
192 8633 : contain_agg_clause(Node *clause)
193 : {
194 8633 : return contain_agg_clause_walker(clause, NULL);
195 : }
196 :
197 : static bool
198 10528 : contain_agg_clause_walker(Node *node, void *context)
199 : {
200 10528 : if (node == NULL)
201 30 : return false;
202 10498 : if (IsA(node, Aggref))
203 : {
204 : Assert(((Aggref *) node)->agglevelsup == 0);
205 794 : return true; /* abort the tree traversal and return true */
206 : }
207 9704 : if (IsA(node, GroupingFunc))
208 : {
209 : Assert(((GroupingFunc *) node)->agglevelsup == 0);
210 25 : return true; /* abort the tree traversal and return true */
211 : }
212 : Assert(!IsA(node, SubLink));
213 9679 : return expression_tree_walker(node, contain_agg_clause_walker, context);
214 : }
215 :
216 : /*****************************************************************************
217 : * Window-function clause manipulation
218 : *****************************************************************************/
219 :
220 : /*
221 : * contain_window_function
222 : * Recursively search for WindowFunc nodes within a clause.
223 : *
224 : * Since window functions don't have level fields, but are hard-wired to
225 : * be associated with the current query level, this is just the same as
226 : * rewriteManip.c's function.
227 : */
228 : bool
229 7367 : contain_window_function(Node *clause)
230 : {
231 7367 : return contain_windowfuncs(clause);
232 : }
233 :
234 : /*
235 : * find_window_functions
236 : * Locate all the WindowFunc nodes in an expression tree, and organize
237 : * them by winref ID number.
238 : *
239 : * Caller must provide an upper bound on the winref IDs expected in the tree.
240 : */
241 : WindowFuncLists *
242 2197 : find_window_functions(Node *clause, Index maxWinRef)
243 : {
244 2197 : WindowFuncLists *lists = palloc_object(WindowFuncLists);
245 :
246 2197 : lists->numWindowFuncs = 0;
247 2197 : lists->maxWinRef = maxWinRef;
248 2197 : lists->windowFuncs = (List **) palloc0((maxWinRef + 1) * sizeof(List *));
249 2197 : (void) find_window_functions_walker(clause, lists);
250 2197 : return lists;
251 : }
252 :
253 : static bool
254 18545 : find_window_functions_walker(Node *node, WindowFuncLists *lists)
255 : {
256 18545 : if (node == NULL)
257 179 : return false;
258 18366 : if (IsA(node, WindowFunc))
259 : {
260 3052 : WindowFunc *wfunc = (WindowFunc *) node;
261 :
262 : /* winref is unsigned, so one-sided test is OK */
263 3052 : if (wfunc->winref > lists->maxWinRef)
264 0 : elog(ERROR, "WindowFunc contains out-of-range winref %u",
265 : wfunc->winref);
266 :
267 6104 : lists->windowFuncs[wfunc->winref] =
268 3052 : lappend(lists->windowFuncs[wfunc->winref], wfunc);
269 3052 : lists->numWindowFuncs++;
270 :
271 : /*
272 : * We assume that the parser checked that there are no window
273 : * functions in the arguments or filter clause. Hence, we need not
274 : * recurse into them. (If either the parser or the planner screws up
275 : * on this point, the executor will still catch it; see ExecInitExpr.)
276 : */
277 3052 : return false;
278 : }
279 : Assert(!IsA(node, SubLink));
280 15314 : return expression_tree_walker(node, find_window_functions_walker, lists);
281 : }
282 :
283 :
284 : /*****************************************************************************
285 : * Support for expressions returning sets
286 : *****************************************************************************/
287 :
288 : /*
289 : * expression_returns_set_rows
290 : * Estimate the number of rows returned by a set-returning expression.
291 : * The result is 1 if it's not a set-returning expression.
292 : *
293 : * We should only examine the top-level function or operator; it used to be
294 : * appropriate to recurse, but not anymore. (Even if there are more SRFs in
295 : * the function's inputs, their multipliers are accounted for separately.)
296 : *
297 : * Note: keep this in sync with expression_returns_set() in nodes/nodeFuncs.c.
298 : */
299 : double
300 328896 : expression_returns_set_rows(PlannerInfo *root, Node *clause)
301 : {
302 328896 : if (clause == NULL)
303 0 : return 1.0;
304 328896 : if (IsA(clause, FuncExpr))
305 : {
306 47454 : FuncExpr *expr = (FuncExpr *) clause;
307 :
308 47454 : if (expr->funcretset)
309 40916 : return clamp_row_est(get_function_rows(root, expr->funcid, clause));
310 : }
311 287980 : if (IsA(clause, OpExpr))
312 : {
313 2620 : OpExpr *expr = (OpExpr *) clause;
314 :
315 2620 : if (expr->opretset)
316 : {
317 5 : set_opfuncid(expr);
318 5 : return clamp_row_est(get_function_rows(root, expr->opfuncid, clause));
319 : }
320 : }
321 287975 : return 1.0;
322 : }
323 :
324 :
325 : /*****************************************************************************
326 : * Subplan clause manipulation
327 : *****************************************************************************/
328 :
329 : /*
330 : * contain_subplans
331 : * Recursively search for subplan nodes within a clause.
332 : *
333 : * If we see a SubLink node, we will return true. This is only possible if
334 : * the expression tree hasn't yet been transformed by subselect.c. We do not
335 : * know whether the node will produce a true subplan or just an initplan,
336 : * but we make the conservative assumption that it will be a subplan.
337 : *
338 : * Returns true if any subplan found.
339 : */
340 : bool
341 41571 : contain_subplans(Node *clause)
342 : {
343 41571 : return contain_subplans_walker(clause, NULL);
344 : }
345 :
346 : static bool
347 174016 : contain_subplans_walker(Node *node, void *context)
348 : {
349 174016 : if (node == NULL)
350 4951 : return false;
351 169065 : if (IsA(node, SubPlan) ||
352 168986 : IsA(node, AlternativeSubPlan) ||
353 168986 : IsA(node, SubLink))
354 248 : return true; /* abort the tree traversal and return true */
355 168817 : return expression_tree_walker(node, contain_subplans_walker, context);
356 : }
357 :
358 :
359 : /*****************************************************************************
360 : * Check clauses for mutable functions
361 : *****************************************************************************/
362 :
363 : /*
364 : * contain_mutable_functions
365 : * Recursively search for mutable functions within a clause.
366 : *
367 : * Returns true if any mutable function (or operator implemented by a
368 : * mutable function) is found. This test is needed so that we don't
369 : * mistakenly think that something like "WHERE random() < 0.5" can be treated
370 : * as a constant qualification.
371 : *
372 : * This will give the right answer only for clauses that have been put
373 : * through expression preprocessing. Callers outside the planner typically
374 : * should use contain_mutable_functions_after_planning() instead, for the
375 : * reasons given there.
376 : *
377 : * We will recursively look into Query nodes (i.e., SubLink sub-selects)
378 : * but not into SubPlans. See comments for contain_volatile_functions().
379 : */
380 : bool
381 119183 : contain_mutable_functions(Node *clause)
382 : {
383 119183 : return contain_mutable_functions_walker(clause, NULL);
384 : }
385 :
386 : static bool
387 89541 : contain_mutable_functions_checker(Oid func_id, void *context)
388 : {
389 89541 : return (func_volatile(func_id) != PROVOLATILE_IMMUTABLE);
390 : }
391 :
392 : static bool
393 321742 : contain_mutable_functions_walker(Node *node, void *context)
394 : {
395 321742 : if (node == NULL)
396 1771 : return false;
397 : /* Check for mutable functions in node itself */
398 319971 : if (check_functions_in_node(node, contain_mutable_functions_checker,
399 : context))
400 5921 : return true;
401 :
402 314050 : if (IsA(node, JsonConstructorExpr))
403 : {
404 176 : const JsonConstructorExpr *ctor = (JsonConstructorExpr *) node;
405 : ListCell *lc;
406 : bool is_jsonb;
407 :
408 176 : is_jsonb = ctor->returning->format->format_type == JS_FORMAT_JSONB;
409 :
410 : /*
411 : * Check argument_type => json[b] conversions specifically. We still
412 : * recurse to check 'args' below, but here we want to specifically
413 : * check whether or not the emitted clause would fail to be immutable
414 : * because of TimeZone, for example.
415 : */
416 296 : foreach(lc, ctor->args)
417 : {
418 264 : Oid typid = exprType(lfirst(lc));
419 :
420 528 : if (is_jsonb ?
421 144 : !to_jsonb_is_immutable(typid) :
422 120 : !to_json_is_immutable(typid))
423 144 : return true;
424 : }
425 :
426 : /* Check all subnodes */
427 : }
428 :
429 313906 : if (IsA(node, JsonExpr))
430 : {
431 188 : JsonExpr *jexpr = castNode(JsonExpr, node);
432 : Const *cnst;
433 :
434 188 : if (!IsA(jexpr->path_spec, Const))
435 0 : return true;
436 :
437 188 : cnst = castNode(Const, jexpr->path_spec);
438 :
439 : Assert(cnst->consttype == JSONPATHOID);
440 188 : if (cnst->constisnull)
441 0 : return false;
442 :
443 188 : if (jspIsMutable(DatumGetJsonPathP(cnst->constvalue),
444 : jexpr->passing_names, jexpr->passing_values))
445 108 : return true;
446 : }
447 :
448 313798 : if (IsA(node, SQLValueFunction))
449 : {
450 : /* all variants of SQLValueFunction are stable */
451 259 : return true;
452 : }
453 :
454 313539 : if (IsA(node, NextValueExpr))
455 : {
456 : /* NextValueExpr is volatile */
457 0 : return true;
458 : }
459 :
460 : /*
461 : * It should be safe to treat MinMaxExpr as immutable, because it will
462 : * depend on a non-cross-type btree comparison function, and those should
463 : * always be immutable. Treating XmlExpr as immutable is more dubious,
464 : * and treating CoerceToDomain as immutable is outright dangerous. But we
465 : * have done so historically, and changing this would probably cause more
466 : * problems than it would fix. In practice, if you have a non-immutable
467 : * domain constraint you are in for pain anyhow.
468 : */
469 :
470 : /* Recurse to check arguments */
471 313539 : if (IsA(node, Query))
472 : {
473 : /* Recurse into subselects */
474 0 : return query_tree_walker((Query *) node,
475 : contain_mutable_functions_walker,
476 : context, 0);
477 : }
478 313539 : return expression_tree_walker(node, contain_mutable_functions_walker,
479 : context);
480 : }
481 :
482 : /*
483 : * contain_mutable_functions_after_planning
484 : * Test whether given expression contains mutable functions.
485 : *
486 : * This is a wrapper for contain_mutable_functions() that is safe to use from
487 : * outside the planner. The difference is that it first runs the expression
488 : * through expression_planner(). There are two key reasons why we need that:
489 : *
490 : * First, function default arguments will get inserted, which may affect
491 : * volatility (consider "default now()").
492 : *
493 : * Second, inline-able functions will get inlined, which may allow us to
494 : * conclude that the function is really less volatile than it's marked.
495 : * As an example, polymorphic functions must be marked with the most volatile
496 : * behavior that they have for any input type, but once we inline the
497 : * function we may be able to conclude that it's not so volatile for the
498 : * particular input type we're dealing with.
499 : */
500 : bool
501 2467 : contain_mutable_functions_after_planning(Expr *expr)
502 : {
503 : /* We assume here that expression_planner() won't scribble on its input */
504 2467 : expr = expression_planner(expr);
505 :
506 : /* Now we can search for non-immutable functions */
507 2467 : return contain_mutable_functions((Node *) expr);
508 : }
509 :
510 :
511 : /*****************************************************************************
512 : * Check clauses for volatile functions
513 : *****************************************************************************/
514 :
515 : /*
516 : * contain_volatile_functions
517 : * Recursively search for volatile functions within a clause.
518 : *
519 : * Returns true if any volatile function (or operator implemented by a
520 : * volatile function) is found. This test prevents, for example,
521 : * invalid conversions of volatile expressions into indexscan quals.
522 : *
523 : * This will give the right answer only for clauses that have been put
524 : * through expression preprocessing. Callers outside the planner typically
525 : * should use contain_volatile_functions_after_planning() instead, for the
526 : * reasons given there.
527 : *
528 : * We will recursively look into Query nodes (i.e., SubLink sub-selects)
529 : * but not into SubPlans. This is a bit odd, but intentional. If we are
530 : * looking at a SubLink, we are probably deciding whether a query tree
531 : * transformation is safe, and a contained sub-select should affect that;
532 : * for example, duplicating a sub-select containing a volatile function
533 : * would be bad. However, once we've got to the stage of having SubPlans,
534 : * subsequent planning need not consider volatility within those, since
535 : * the executor won't change its evaluation rules for a SubPlan based on
536 : * volatility.
537 : *
538 : * For some node types, for example, RestrictInfo and PathTarget, we cache
539 : * whether we found any volatile functions or not and reuse that value in any
540 : * future checks for that node. All of the logic for determining if the
541 : * cached value should be set to VOLATILITY_NOVOLATILE or VOLATILITY_VOLATILE
542 : * belongs in this function. Any code which makes changes to these nodes
543 : * which could change the outcome this function must set the cached value back
544 : * to VOLATILITY_UNKNOWN. That allows this function to redetermine the
545 : * correct value during the next call, should we need to redetermine if the
546 : * node contains any volatile functions again in the future.
547 : */
548 : bool
549 2649750 : contain_volatile_functions(Node *clause)
550 : {
551 2649750 : return contain_volatile_functions_walker(clause, NULL);
552 : }
553 :
554 : static bool
555 751890 : contain_volatile_functions_checker(Oid func_id, void *context)
556 : {
557 751890 : return (func_volatile(func_id) == PROVOLATILE_VOLATILE);
558 : }
559 :
560 : static bool
561 6101223 : contain_volatile_functions_walker(Node *node, void *context)
562 : {
563 6101223 : if (node == NULL)
564 185003 : return false;
565 : /* Check for volatile functions in node itself */
566 5916220 : if (check_functions_in_node(node, contain_volatile_functions_checker,
567 : context))
568 1599 : return true;
569 :
570 5914621 : if (IsA(node, NextValueExpr))
571 : {
572 : /* NextValueExpr is volatile */
573 28 : return true;
574 : }
575 :
576 5914593 : if (IsA(node, RestrictInfo))
577 : {
578 1012914 : RestrictInfo *rinfo = (RestrictInfo *) node;
579 :
580 : /*
581 : * For RestrictInfo, check if we've checked the volatility of it
582 : * before. If so, we can just use the cached value and not bother
583 : * checking it again. Otherwise, check it and cache if whether we
584 : * found any volatile functions.
585 : */
586 1012914 : if (rinfo->has_volatile == VOLATILITY_NOVOLATILE)
587 610432 : return false;
588 402482 : else if (rinfo->has_volatile == VOLATILITY_VOLATILE)
589 54 : return true;
590 : else
591 : {
592 : bool hasvolatile;
593 :
594 402428 : hasvolatile = contain_volatile_functions_walker((Node *) rinfo->clause,
595 : context);
596 402428 : if (hasvolatile)
597 98 : rinfo->has_volatile = VOLATILITY_VOLATILE;
598 : else
599 402330 : rinfo->has_volatile = VOLATILITY_NOVOLATILE;
600 :
601 402428 : return hasvolatile;
602 : }
603 : }
604 :
605 4901679 : if (IsA(node, PathTarget))
606 : {
607 279203 : PathTarget *target = (PathTarget *) node;
608 :
609 : /*
610 : * We also do caching for PathTarget the same as we do above for
611 : * RestrictInfos.
612 : */
613 279203 : if (target->has_volatile_expr == VOLATILITY_NOVOLATILE)
614 231592 : return false;
615 47611 : else if (target->has_volatile_expr == VOLATILITY_VOLATILE)
616 0 : return true;
617 : else
618 : {
619 : bool hasvolatile;
620 :
621 47611 : hasvolatile = contain_volatile_functions_walker((Node *) target->exprs,
622 : context);
623 :
624 47611 : if (hasvolatile)
625 0 : target->has_volatile_expr = VOLATILITY_VOLATILE;
626 : else
627 47611 : target->has_volatile_expr = VOLATILITY_NOVOLATILE;
628 :
629 47611 : return hasvolatile;
630 : }
631 : }
632 :
633 : /*
634 : * See notes in contain_mutable_functions_walker about why we treat
635 : * MinMaxExpr, XmlExpr, and CoerceToDomain as immutable, while
636 : * SQLValueFunction is stable. Hence, none of them are of interest here.
637 : */
638 :
639 : /* Recurse to check arguments */
640 4622476 : if (IsA(node, Query))
641 : {
642 : /* Recurse into subselects */
643 5418 : return query_tree_walker((Query *) node,
644 : contain_volatile_functions_walker,
645 : context, 0);
646 : }
647 4617058 : return expression_tree_walker(node, contain_volatile_functions_walker,
648 : context);
649 : }
650 :
651 : /*
652 : * contain_volatile_functions_after_planning
653 : * Test whether given expression contains volatile functions.
654 : *
655 : * This is a wrapper for contain_volatile_functions() that is safe to use from
656 : * outside the planner. The difference is that it first runs the expression
657 : * through expression_planner(). There are two key reasons why we need that:
658 : *
659 : * First, function default arguments will get inserted, which may affect
660 : * volatility (consider "default random()").
661 : *
662 : * Second, inline-able functions will get inlined, which may allow us to
663 : * conclude that the function is really less volatile than it's marked.
664 : * As an example, polymorphic functions must be marked with the most volatile
665 : * behavior that they have for any input type, but once we inline the
666 : * function we may be able to conclude that it's not so volatile for the
667 : * particular input type we're dealing with.
668 : */
669 : bool
670 843 : contain_volatile_functions_after_planning(Expr *expr)
671 : {
672 : /* We assume here that expression_planner() won't scribble on its input */
673 843 : expr = expression_planner(expr);
674 :
675 : /* Now we can search for volatile functions */
676 835 : return contain_volatile_functions((Node *) expr);
677 : }
678 :
679 : /*
680 : * Special purpose version of contain_volatile_functions() for use in COPY:
681 : * ignore nextval(), but treat all other functions normally.
682 : */
683 : bool
684 159 : contain_volatile_functions_not_nextval(Node *clause)
685 : {
686 159 : return contain_volatile_functions_not_nextval_walker(clause, NULL);
687 : }
688 :
689 : static bool
690 41 : contain_volatile_functions_not_nextval_checker(Oid func_id, void *context)
691 : {
692 66 : return (func_id != F_NEXTVAL &&
693 25 : func_volatile(func_id) == PROVOLATILE_VOLATILE);
694 : }
695 :
696 : static bool
697 199 : contain_volatile_functions_not_nextval_walker(Node *node, void *context)
698 : {
699 199 : if (node == NULL)
700 0 : return false;
701 : /* Check for volatile functions in node itself */
702 199 : if (check_functions_in_node(node,
703 : contain_volatile_functions_not_nextval_checker,
704 : context))
705 4 : return true;
706 :
707 : /*
708 : * See notes in contain_mutable_functions_walker about why we treat
709 : * MinMaxExpr, XmlExpr, and CoerceToDomain as immutable, while
710 : * SQLValueFunction is stable. Hence, none of them are of interest here.
711 : * Also, since we're intentionally ignoring nextval(), presumably we
712 : * should ignore NextValueExpr.
713 : */
714 :
715 : /* Recurse to check arguments */
716 195 : if (IsA(node, Query))
717 : {
718 : /* Recurse into subselects */
719 0 : return query_tree_walker((Query *) node,
720 : contain_volatile_functions_not_nextval_walker,
721 : context, 0);
722 : }
723 195 : return expression_tree_walker(node,
724 : contain_volatile_functions_not_nextval_walker,
725 : context);
726 : }
727 :
728 :
729 : /*****************************************************************************
730 : * Check queries for parallel unsafe and/or restricted constructs
731 : *****************************************************************************/
732 :
733 : /*
734 : * max_parallel_hazard
735 : * Find the worst parallel-hazard level in the given query
736 : *
737 : * Returns the worst function hazard property (the earliest in this list:
738 : * PROPARALLEL_UNSAFE, PROPARALLEL_RESTRICTED, PROPARALLEL_SAFE) that can
739 : * be found in the given parsetree. We use this to find out whether the query
740 : * can be parallelized at all. The caller will also save the result in
741 : * PlannerGlobal so as to short-circuit checks of portions of the querytree
742 : * later, in the common case where everything is SAFE.
743 : */
744 : char
745 256728 : max_parallel_hazard(Query *parse)
746 : {
747 : max_parallel_hazard_context context;
748 :
749 256728 : context.max_hazard = PROPARALLEL_SAFE;
750 256728 : context.max_interesting = PROPARALLEL_UNSAFE;
751 256728 : context.safe_param_ids = NIL;
752 256728 : (void) max_parallel_hazard_walker((Node *) parse, &context);
753 256728 : return context.max_hazard;
754 : }
755 :
756 : /*
757 : * is_parallel_safe
758 : * Detect whether the given expr contains only parallel-safe functions
759 : *
760 : * root->glob->maxParallelHazard must previously have been set to the
761 : * result of max_parallel_hazard() on the whole query.
762 : */
763 : bool
764 1887944 : is_parallel_safe(PlannerInfo *root, Node *node)
765 : {
766 : max_parallel_hazard_context context;
767 : PlannerInfo *proot;
768 : ListCell *l;
769 :
770 : /*
771 : * Even if the original querytree contained nothing unsafe, we need to
772 : * search the expression if we have generated any PARAM_EXEC Params while
773 : * planning, because those are parallel-restricted and there might be one
774 : * in this expression. But otherwise we don't need to look.
775 : */
776 1887944 : if (root->glob->maxParallelHazard == PROPARALLEL_SAFE &&
777 1144134 : root->glob->paramExecTypes == NIL)
778 1117200 : return true;
779 : /* Else use max_parallel_hazard's search logic, but stop on RESTRICTED */
780 770744 : context.max_hazard = PROPARALLEL_SAFE;
781 770744 : context.max_interesting = PROPARALLEL_RESTRICTED;
782 770744 : context.safe_param_ids = NIL;
783 :
784 : /*
785 : * The params that refer to the same or parent query level are considered
786 : * parallel-safe. The idea is that we compute such params at Gather or
787 : * Gather Merge node and pass their value to workers.
788 : */
789 1882713 : for (proot = root; proot != NULL; proot = proot->parent_root)
790 : {
791 1165680 : foreach(l, proot->init_plans)
792 : {
793 53711 : SubPlan *initsubplan = (SubPlan *) lfirst(l);
794 :
795 53711 : context.safe_param_ids = list_concat(context.safe_param_ids,
796 53711 : initsubplan->setParam);
797 : }
798 : }
799 :
800 770744 : return !max_parallel_hazard_walker(node, &context);
801 : }
802 :
803 : /* core logic for all parallel-hazard checks */
804 : static bool
805 1290843 : max_parallel_hazard_test(char proparallel, max_parallel_hazard_context *context)
806 : {
807 1290843 : switch (proparallel)
808 : {
809 1083758 : case PROPARALLEL_SAFE:
810 : /* nothing to see here, move along */
811 1083758 : break;
812 156153 : case PROPARALLEL_RESTRICTED:
813 : /* increase max_hazard to RESTRICTED */
814 : Assert(context->max_hazard != PROPARALLEL_UNSAFE);
815 156153 : context->max_hazard = proparallel;
816 : /* done if we are not expecting any unsafe functions */
817 156153 : if (context->max_interesting == proparallel)
818 77377 : return true;
819 78776 : break;
820 50932 : case PROPARALLEL_UNSAFE:
821 50932 : context->max_hazard = proparallel;
822 : /* we're always done at the first unsafe construct */
823 50932 : return true;
824 0 : default:
825 0 : elog(ERROR, "unrecognized proparallel value \"%c\"", proparallel);
826 : break;
827 : }
828 1162534 : return false;
829 : }
830 :
831 : /* check_functions_in_node callback */
832 : static bool
833 1176452 : max_parallel_hazard_checker(Oid func_id, void *context)
834 : {
835 1176452 : return max_parallel_hazard_test(func_parallel(func_id),
836 : (max_parallel_hazard_context *) context);
837 : }
838 :
839 : static bool
840 16852450 : max_parallel_hazard_walker(Node *node, max_parallel_hazard_context *context)
841 : {
842 16852450 : if (node == NULL)
843 4689021 : return false;
844 :
845 : /* Check for hazardous functions in node itself */
846 12163429 : if (check_functions_in_node(node, max_parallel_hazard_checker,
847 : context))
848 67022 : return true;
849 :
850 : /*
851 : * It should be OK to treat MinMaxExpr as parallel-safe, since btree
852 : * opclass support functions are generally parallel-safe. XmlExpr is a
853 : * bit more dubious but we can probably get away with it. We err on the
854 : * side of caution by treating CoerceToDomain as parallel-restricted.
855 : * (Note: in principle that's wrong because a domain constraint could
856 : * contain a parallel-unsafe function; but useful constraints probably
857 : * never would have such, and assuming they do would cripple use of
858 : * parallel query in the presence of domain types.) SQLValueFunction
859 : * should be safe in all cases. NextValueExpr is parallel-unsafe.
860 : */
861 12096407 : if (IsA(node, CoerceToDomain))
862 : {
863 15791 : if (max_parallel_hazard_test(PROPARALLEL_RESTRICTED, context))
864 4331 : return true;
865 : }
866 :
867 12080616 : else if (IsA(node, NextValueExpr))
868 : {
869 321 : if (max_parallel_hazard_test(PROPARALLEL_UNSAFE, context))
870 321 : return true;
871 : }
872 :
873 : /*
874 : * Treat window functions as parallel-restricted because we aren't sure
875 : * whether the input row ordering is fully deterministic, and the output
876 : * of window functions might vary across workers if not. (In some cases,
877 : * like where the window frame orders by a primary key, we could relax
878 : * this restriction. But it doesn't currently seem worth expending extra
879 : * effort to do so.)
880 : */
881 12080295 : else if (IsA(node, WindowFunc))
882 : {
883 5106 : if (max_parallel_hazard_test(PROPARALLEL_RESTRICTED, context))
884 2258 : return true;
885 : }
886 :
887 : /*
888 : * As a notational convenience for callers, look through RestrictInfo.
889 : */
890 12075189 : else if (IsA(node, RestrictInfo))
891 : {
892 199518 : RestrictInfo *rinfo = (RestrictInfo *) node;
893 :
894 199518 : return max_parallel_hazard_walker((Node *) rinfo->clause, context);
895 : }
896 :
897 : /*
898 : * Really we should not see SubLink during a max_interesting == restricted
899 : * scan, but if we do, return true.
900 : */
901 11875671 : else if (IsA(node, SubLink))
902 : {
903 34695 : if (max_parallel_hazard_test(PROPARALLEL_RESTRICTED, context))
904 0 : return true;
905 : }
906 :
907 : /*
908 : * Only parallel-safe SubPlans can be sent to workers. Within the
909 : * testexpr of the SubPlan, Params representing the output columns of the
910 : * subplan can be treated as parallel-safe, so temporarily add their IDs
911 : * to the safe_param_ids list while examining the testexpr.
912 : */
913 11840976 : else if (IsA(node, SubPlan))
914 : {
915 24806 : SubPlan *subplan = (SubPlan *) node;
916 : List *save_safe_param_ids;
917 :
918 49347 : if (!subplan->parallel_safe &&
919 24541 : max_parallel_hazard_test(PROPARALLEL_RESTRICTED, context))
920 24541 : return true;
921 265 : save_safe_param_ids = context->safe_param_ids;
922 530 : context->safe_param_ids = list_concat_copy(context->safe_param_ids,
923 265 : subplan->paramIds);
924 265 : if (max_parallel_hazard_walker(subplan->testexpr, context))
925 5 : return true; /* no need to restore safe_param_ids */
926 260 : list_free(context->safe_param_ids);
927 260 : context->safe_param_ids = save_safe_param_ids;
928 : /* we must also check args, but no special Param treatment there */
929 260 : if (max_parallel_hazard_walker((Node *) subplan->args, context))
930 0 : return true;
931 : /* don't want to recurse normally, so we're done */
932 260 : return false;
933 : }
934 :
935 : /*
936 : * We can't pass Params to workers at the moment either, so they are also
937 : * parallel-restricted, unless they are PARAM_EXTERN Params or are
938 : * PARAM_EXEC Params listed in safe_param_ids, meaning they could be
939 : * either generated within workers or can be computed by the leader and
940 : * then their value can be passed to workers.
941 : */
942 11816170 : else if (IsA(node, Param))
943 : {
944 82716 : Param *param = (Param *) node;
945 :
946 82716 : if (param->paramkind == PARAM_EXTERN)
947 40822 : return false;
948 :
949 41894 : if (param->paramkind != PARAM_EXEC ||
950 37740 : !list_member_int(context->safe_param_ids, param->paramid))
951 : {
952 33937 : if (max_parallel_hazard_test(PROPARALLEL_RESTRICTED, context))
953 29836 : return true;
954 : }
955 12058 : return false; /* nothing to recurse to */
956 : }
957 :
958 : /*
959 : * When we're first invoked on a completely unplanned tree, we must
960 : * recurse into subqueries so to as to locate parallel-unsafe constructs
961 : * anywhere in the tree.
962 : */
963 11733454 : else if (IsA(node, Query))
964 : {
965 342343 : Query *query = (Query *) node;
966 :
967 : /* SELECT FOR UPDATE/SHARE must be treated as unsafe */
968 342343 : if (query->rowMarks != NULL)
969 : {
970 3849 : context->max_hazard = PROPARALLEL_UNSAFE;
971 3849 : return true;
972 : }
973 :
974 : /* Recurse into subselects */
975 338494 : return query_tree_walker(query,
976 : max_parallel_hazard_walker,
977 : context, 0);
978 : }
979 :
980 : /* Recurse to check arguments */
981 11440114 : return expression_tree_walker(node,
982 : max_parallel_hazard_walker,
983 : context);
984 : }
985 :
986 :
987 : /*****************************************************************************
988 : * Check clauses for nonstrict functions
989 : *****************************************************************************/
990 :
991 : /*
992 : * contain_nonstrict_functions
993 : * Recursively search for nonstrict functions within a clause.
994 : *
995 : * Returns true if any nonstrict construct is found --- ie, anything that
996 : * could produce non-NULL output with a NULL input.
997 : *
998 : * The idea here is that the caller has verified that the expression contains
999 : * one or more Var or Param nodes (as appropriate for the caller's need), and
1000 : * now wishes to prove that the expression result will be NULL if any of these
1001 : * inputs is NULL. If we return false, then the proof succeeded.
1002 : */
1003 : bool
1004 1903 : contain_nonstrict_functions(Node *clause)
1005 : {
1006 1903 : return contain_nonstrict_functions_walker(clause, NULL);
1007 : }
1008 :
1009 : static bool
1010 1985 : contain_nonstrict_functions_checker(Oid func_id, void *context)
1011 : {
1012 1985 : return !func_strict(func_id);
1013 : }
1014 :
1015 : static bool
1016 6691 : contain_nonstrict_functions_walker(Node *node, void *context)
1017 : {
1018 6691 : if (node == NULL)
1019 0 : return false;
1020 6691 : if (IsA(node, Aggref))
1021 : {
1022 : /* an aggregate could return non-null with null input */
1023 0 : return true;
1024 : }
1025 6691 : if (IsA(node, GroupingFunc))
1026 : {
1027 : /*
1028 : * A GroupingFunc doesn't evaluate its arguments, and therefore must
1029 : * be treated as nonstrict.
1030 : */
1031 0 : return true;
1032 : }
1033 6691 : if (IsA(node, WindowFunc))
1034 : {
1035 : /* a window function could return non-null with null input */
1036 0 : return true;
1037 : }
1038 6691 : if (IsA(node, SubscriptingRef))
1039 : {
1040 0 : SubscriptingRef *sbsref = (SubscriptingRef *) node;
1041 : const SubscriptRoutines *sbsroutines;
1042 :
1043 : /* Subscripting assignment is always presumed nonstrict */
1044 0 : if (sbsref->refassgnexpr != NULL)
1045 0 : return true;
1046 : /* Otherwise we must look up the subscripting support methods */
1047 0 : sbsroutines = getSubscriptingRoutines(sbsref->refcontainertype, NULL);
1048 0 : if (!(sbsroutines && sbsroutines->fetch_strict))
1049 0 : return true;
1050 : /* else fall through to check args */
1051 : }
1052 6691 : if (IsA(node, DistinctExpr))
1053 : {
1054 : /* IS DISTINCT FROM is inherently non-strict */
1055 0 : return true;
1056 : }
1057 6691 : if (IsA(node, NullIfExpr))
1058 : {
1059 : /* NULLIF is inherently non-strict */
1060 0 : return true;
1061 : }
1062 6691 : if (IsA(node, BoolExpr))
1063 : {
1064 15 : BoolExpr *expr = (BoolExpr *) node;
1065 :
1066 15 : switch (expr->boolop)
1067 : {
1068 15 : case AND_EXPR:
1069 : case OR_EXPR:
1070 : /* AND, OR are inherently non-strict */
1071 15 : return true;
1072 0 : default:
1073 0 : break;
1074 : }
1075 : }
1076 6676 : if (IsA(node, SubLink))
1077 : {
1078 : /* In some cases a sublink might be strict, but in general not */
1079 10 : return true;
1080 : }
1081 6666 : if (IsA(node, SubPlan))
1082 0 : return true;
1083 6666 : if (IsA(node, AlternativeSubPlan))
1084 0 : return true;
1085 6666 : if (IsA(node, FieldStore))
1086 0 : return true;
1087 6666 : if (IsA(node, CoerceViaIO))
1088 : {
1089 : /*
1090 : * CoerceViaIO is strict regardless of whether the I/O functions are,
1091 : * so just go look at its argument; asking check_functions_in_node is
1092 : * useless expense and could deliver the wrong answer.
1093 : */
1094 877 : return contain_nonstrict_functions_walker((Node *) ((CoerceViaIO *) node)->arg,
1095 : context);
1096 : }
1097 5789 : if (IsA(node, ArrayCoerceExpr))
1098 : {
1099 : /*
1100 : * ArrayCoerceExpr is strict at the array level, regardless of what
1101 : * the per-element expression is; so we should ignore elemexpr and
1102 : * recurse only into the arg.
1103 : */
1104 0 : return contain_nonstrict_functions_walker((Node *) ((ArrayCoerceExpr *) node)->arg,
1105 : context);
1106 : }
1107 5789 : if (IsA(node, CaseExpr))
1108 52 : return true;
1109 5737 : if (IsA(node, ArrayExpr))
1110 0 : return true;
1111 5737 : if (IsA(node, RowExpr))
1112 2 : return true;
1113 5735 : if (IsA(node, RowCompareExpr))
1114 0 : return true;
1115 5735 : if (IsA(node, CoalesceExpr))
1116 211 : return true;
1117 5524 : if (IsA(node, MinMaxExpr))
1118 50 : return true;
1119 5474 : if (IsA(node, XmlExpr))
1120 0 : return true;
1121 5474 : if (IsA(node, NullTest))
1122 20 : return true;
1123 5454 : if (IsA(node, BooleanTest))
1124 0 : return true;
1125 5454 : if (IsA(node, JsonConstructorExpr))
1126 10 : return true;
1127 :
1128 : /* Check other function-containing nodes */
1129 5444 : if (check_functions_in_node(node, contain_nonstrict_functions_checker,
1130 : context))
1131 0 : return true;
1132 :
1133 5444 : return expression_tree_walker(node, contain_nonstrict_functions_walker,
1134 : context);
1135 : }
1136 :
1137 : /*****************************************************************************
1138 : * Check clauses for Params
1139 : *****************************************************************************/
1140 :
1141 : /*
1142 : * contain_exec_param
1143 : * Recursively search for PARAM_EXEC Params within a clause.
1144 : *
1145 : * Returns true if the clause contains any PARAM_EXEC Param with a paramid
1146 : * appearing in the given list of Param IDs. Does not descend into
1147 : * subqueries!
1148 : */
1149 : bool
1150 2439 : contain_exec_param(Node *clause, List *param_ids)
1151 : {
1152 2439 : return contain_exec_param_walker(clause, param_ids);
1153 : }
1154 :
1155 : static bool
1156 2679 : contain_exec_param_walker(Node *node, List *param_ids)
1157 : {
1158 2679 : if (node == NULL)
1159 30 : return false;
1160 2649 : if (IsA(node, Param))
1161 : {
1162 10 : Param *p = (Param *) node;
1163 :
1164 20 : if (p->paramkind == PARAM_EXEC &&
1165 10 : list_member_int(param_ids, p->paramid))
1166 10 : return true;
1167 : }
1168 2639 : return expression_tree_walker(node, contain_exec_param_walker, param_ids);
1169 : }
1170 :
1171 : /*****************************************************************************
1172 : * Check clauses for context-dependent nodes
1173 : *****************************************************************************/
1174 :
1175 : /*
1176 : * contain_context_dependent_node
1177 : * Recursively search for context-dependent nodes within a clause.
1178 : *
1179 : * CaseTestExpr nodes must appear directly within the corresponding CaseExpr,
1180 : * not nested within another one, or they'll see the wrong test value. If one
1181 : * appears "bare" in the arguments of a SQL function, then we can't inline the
1182 : * SQL function for fear of creating such a situation. The same applies for
1183 : * CaseTestExpr used within the elemexpr of an ArrayCoerceExpr.
1184 : *
1185 : * CoerceToDomainValue would have the same issue if domain CHECK expressions
1186 : * could get inlined into larger expressions, but presently that's impossible.
1187 : * Still, it might be allowed in future, or other node types with similar
1188 : * issues might get invented. So give this function a generic name, and set
1189 : * up the recursion state to allow multiple flag bits.
1190 : */
1191 : static bool
1192 2551 : contain_context_dependent_node(Node *clause)
1193 : {
1194 2551 : int flags = 0;
1195 :
1196 2551 : return contain_context_dependent_node_walker(clause, &flags);
1197 : }
1198 :
1199 : #define CCDN_CASETESTEXPR_OK 0x0001 /* CaseTestExpr okay here? */
1200 :
1201 : static bool
1202 7847 : contain_context_dependent_node_walker(Node *node, int *flags)
1203 : {
1204 7847 : if (node == NULL)
1205 136 : return false;
1206 7711 : if (IsA(node, CaseTestExpr))
1207 5 : return !(*flags & CCDN_CASETESTEXPR_OK);
1208 7706 : else if (IsA(node, CaseExpr))
1209 : {
1210 0 : CaseExpr *caseexpr = (CaseExpr *) node;
1211 :
1212 : /*
1213 : * If this CASE doesn't have a test expression, then it doesn't create
1214 : * a context in which CaseTestExprs should appear, so just fall
1215 : * through and treat it as a generic expression node.
1216 : */
1217 0 : if (caseexpr->arg)
1218 : {
1219 0 : int save_flags = *flags;
1220 : bool res;
1221 :
1222 : /*
1223 : * Note: in principle, we could distinguish the various sub-parts
1224 : * of a CASE construct and set the flag bit only for some of them,
1225 : * since we are only expecting CaseTestExprs to appear in the
1226 : * "expr" subtree of the CaseWhen nodes. But it doesn't really
1227 : * seem worth any extra code. If there are any bare CaseTestExprs
1228 : * elsewhere in the CASE, something's wrong already.
1229 : */
1230 0 : *flags |= CCDN_CASETESTEXPR_OK;
1231 0 : res = expression_tree_walker(node,
1232 : contain_context_dependent_node_walker,
1233 : flags);
1234 0 : *flags = save_flags;
1235 0 : return res;
1236 : }
1237 : }
1238 7706 : else if (IsA(node, ArrayCoerceExpr))
1239 : {
1240 0 : ArrayCoerceExpr *ac = (ArrayCoerceExpr *) node;
1241 : int save_flags;
1242 : bool res;
1243 :
1244 : /* Check the array expression */
1245 0 : if (contain_context_dependent_node_walker((Node *) ac->arg, flags))
1246 0 : return true;
1247 :
1248 : /* Check the elemexpr, which is allowed to contain CaseTestExpr */
1249 0 : save_flags = *flags;
1250 0 : *flags |= CCDN_CASETESTEXPR_OK;
1251 0 : res = contain_context_dependent_node_walker((Node *) ac->elemexpr,
1252 : flags);
1253 0 : *flags = save_flags;
1254 0 : return res;
1255 : }
1256 7706 : return expression_tree_walker(node, contain_context_dependent_node_walker,
1257 : flags);
1258 : }
1259 :
1260 : /*****************************************************************************
1261 : * Check clauses for Vars passed to non-leakproof functions
1262 : *****************************************************************************/
1263 :
1264 : /*
1265 : * contain_leaked_vars
1266 : * Recursively scan a clause to discover whether it contains any Var
1267 : * nodes (of the current query level) that are passed as arguments to
1268 : * leaky functions.
1269 : *
1270 : * Returns true if the clause contains any non-leakproof functions that are
1271 : * passed Var nodes of the current query level, and which might therefore leak
1272 : * data. Such clauses must be applied after any lower-level security barrier
1273 : * clauses.
1274 : */
1275 : bool
1276 6677 : contain_leaked_vars(Node *clause)
1277 : {
1278 6677 : return contain_leaked_vars_walker(clause, NULL);
1279 : }
1280 :
1281 : static bool
1282 6577 : contain_leaked_vars_checker(Oid func_id, void *context)
1283 : {
1284 6577 : return !get_func_leakproof(func_id);
1285 : }
1286 :
1287 : static bool
1288 15132 : contain_leaked_vars_walker(Node *node, void *context)
1289 : {
1290 15132 : if (node == NULL)
1291 0 : return false;
1292 :
1293 15132 : switch (nodeTag(node))
1294 : {
1295 8495 : case T_Var:
1296 : case T_Const:
1297 : case T_Param:
1298 : case T_ArrayExpr:
1299 : case T_FieldSelect:
1300 : case T_FieldStore:
1301 : case T_NamedArgExpr:
1302 : case T_BoolExpr:
1303 : case T_RelabelType:
1304 : case T_CollateExpr:
1305 : case T_CaseExpr:
1306 : case T_CaseTestExpr:
1307 : case T_RowExpr:
1308 : case T_SQLValueFunction:
1309 : case T_NullTest:
1310 : case T_BooleanTest:
1311 : case T_NextValueExpr:
1312 : case T_ReturningExpr:
1313 : case T_List:
1314 :
1315 : /*
1316 : * We know these node types don't contain function calls; but
1317 : * something further down in the node tree might.
1318 : */
1319 8495 : break;
1320 :
1321 6577 : case T_FuncExpr:
1322 : case T_OpExpr:
1323 : case T_DistinctExpr:
1324 : case T_NullIfExpr:
1325 : case T_ScalarArrayOpExpr:
1326 : case T_CoerceViaIO:
1327 : case T_ArrayCoerceExpr:
1328 :
1329 : /*
1330 : * If node contains a leaky function call, and there's any Var
1331 : * underneath it, reject.
1332 : */
1333 6577 : if (check_functions_in_node(node, contain_leaked_vars_checker,
1334 2390 : context) &&
1335 2390 : contain_var_clause(node))
1336 2346 : return true;
1337 4231 : break;
1338 :
1339 0 : case T_SubscriptingRef:
1340 : {
1341 0 : SubscriptingRef *sbsref = (SubscriptingRef *) node;
1342 : const SubscriptRoutines *sbsroutines;
1343 :
1344 : /* Consult the subscripting support method info */
1345 0 : sbsroutines = getSubscriptingRoutines(sbsref->refcontainertype,
1346 : NULL);
1347 0 : if (!sbsroutines ||
1348 0 : !(sbsref->refassgnexpr != NULL ?
1349 0 : sbsroutines->store_leakproof :
1350 0 : sbsroutines->fetch_leakproof))
1351 : {
1352 : /* Node is leaky, so reject if it contains Vars */
1353 0 : if (contain_var_clause(node))
1354 0 : return true;
1355 : }
1356 : }
1357 0 : break;
1358 :
1359 0 : case T_RowCompareExpr:
1360 : {
1361 : /*
1362 : * It's worth special-casing this because a leaky comparison
1363 : * function only compromises one pair of row elements, which
1364 : * might not contain Vars while others do.
1365 : */
1366 0 : RowCompareExpr *rcexpr = (RowCompareExpr *) node;
1367 : ListCell *opid;
1368 : ListCell *larg;
1369 : ListCell *rarg;
1370 :
1371 0 : forthree(opid, rcexpr->opnos,
1372 : larg, rcexpr->largs,
1373 : rarg, rcexpr->rargs)
1374 : {
1375 0 : Oid funcid = get_opcode(lfirst_oid(opid));
1376 :
1377 0 : if (!get_func_leakproof(funcid) &&
1378 0 : (contain_var_clause((Node *) lfirst(larg)) ||
1379 0 : contain_var_clause((Node *) lfirst(rarg))))
1380 0 : return true;
1381 : }
1382 : }
1383 0 : break;
1384 :
1385 0 : case T_MinMaxExpr:
1386 : {
1387 : /*
1388 : * MinMaxExpr is leakproof if the comparison function it calls
1389 : * is leakproof.
1390 : */
1391 0 : MinMaxExpr *minmaxexpr = (MinMaxExpr *) node;
1392 : TypeCacheEntry *typentry;
1393 : bool leakproof;
1394 :
1395 : /* Look up the btree comparison function for the datatype */
1396 0 : typentry = lookup_type_cache(minmaxexpr->minmaxtype,
1397 : TYPECACHE_CMP_PROC);
1398 0 : if (OidIsValid(typentry->cmp_proc))
1399 0 : leakproof = get_func_leakproof(typentry->cmp_proc);
1400 : else
1401 : {
1402 : /*
1403 : * The executor will throw an error, but here we just
1404 : * treat the missing function as leaky.
1405 : */
1406 0 : leakproof = false;
1407 : }
1408 :
1409 0 : if (!leakproof &&
1410 0 : contain_var_clause((Node *) minmaxexpr->args))
1411 0 : return true;
1412 : }
1413 0 : break;
1414 :
1415 35 : case T_CurrentOfExpr:
1416 :
1417 : /*
1418 : * WHERE CURRENT OF doesn't contain leaky function calls.
1419 : * Moreover, it is essential that this is considered non-leaky,
1420 : * since the planner must always generate a TID scan when CURRENT
1421 : * OF is present -- cf. cost_tidscan.
1422 : */
1423 35 : return false;
1424 :
1425 25 : default:
1426 :
1427 : /*
1428 : * If we don't recognize the node tag, assume it might be leaky.
1429 : * This prevents an unexpected security hole if someone adds a new
1430 : * node type that can call a function.
1431 : */
1432 25 : return true;
1433 : }
1434 12726 : return expression_tree_walker(node, contain_leaked_vars_walker,
1435 : context);
1436 : }
1437 :
1438 : /*****************************************************************************
1439 : * Nullability analysis
1440 : *****************************************************************************/
1441 :
1442 : /*
1443 : * find_nonnullable_rels
1444 : * Determine which base rels are forced nonnullable by given clause.
1445 : *
1446 : * Returns the set of all Relids that are referenced in the clause in such
1447 : * a way that the clause cannot possibly return TRUE if any of these Relids
1448 : * is an all-NULL row. (It is OK to err on the side of conservatism; hence
1449 : * the analysis here is simplistic.)
1450 : *
1451 : * The semantics here are subtly different from contain_nonstrict_functions:
1452 : * that function is concerned with NULL results from arbitrary expressions,
1453 : * but here we assume that the input is a Boolean expression, and wish to
1454 : * see if NULL inputs will provably cause a FALSE-or-NULL result. We expect
1455 : * the expression to have been AND/OR flattened and converted to implicit-AND
1456 : * format.
1457 : *
1458 : * Note: this function is largely duplicative of find_nonnullable_vars().
1459 : * The reason not to simplify this function into a thin wrapper around
1460 : * find_nonnullable_vars() is that the tested conditions really are different:
1461 : * a clause like "t1.v1 IS NOT NULL OR t1.v2 IS NOT NULL" does not prove
1462 : * that either v1 or v2 can't be NULL, but it does prove that the t1 row
1463 : * as a whole can't be all-NULL. Also, the behavior for PHVs is different.
1464 : *
1465 : * top_level is true while scanning top-level AND/OR structure; here, showing
1466 : * the result is either FALSE or NULL is good enough. top_level is false when
1467 : * we have descended below a NOT or a strict function: now we must be able to
1468 : * prove that the subexpression goes to NULL.
1469 : *
1470 : * We don't use expression_tree_walker here because we don't want to descend
1471 : * through very many kinds of nodes; only the ones we can be sure are strict.
1472 : */
1473 : Relids
1474 81926 : find_nonnullable_rels(Node *clause)
1475 : {
1476 81926 : return find_nonnullable_rels_walker(clause, true);
1477 : }
1478 :
1479 : static Relids
1480 543690 : find_nonnullable_rels_walker(Node *node, bool top_level)
1481 : {
1482 543690 : Relids result = NULL;
1483 : ListCell *l;
1484 :
1485 543690 : if (node == NULL)
1486 5019 : return NULL;
1487 538671 : if (IsA(node, Var))
1488 : {
1489 173488 : Var *var = (Var *) node;
1490 :
1491 173488 : if (var->varlevelsup == 0)
1492 173488 : result = bms_make_singleton(var->varno);
1493 : }
1494 365183 : else if (IsA(node, List))
1495 : {
1496 : /*
1497 : * At top level, we are examining an implicit-AND list: if any of the
1498 : * arms produces FALSE-or-NULL then the result is FALSE-or-NULL. If
1499 : * not at top level, we are examining the arguments of a strict
1500 : * function: if any of them produce NULL then the result of the
1501 : * function must be NULL. So in both cases, the set of nonnullable
1502 : * rels is the union of those found in the arms, and we pass down the
1503 : * top_level flag unmodified.
1504 : */
1505 524253 : foreach(l, (List *) node)
1506 : {
1507 333276 : result = bms_join(result,
1508 333276 : find_nonnullable_rels_walker(lfirst(l),
1509 : top_level));
1510 : }
1511 : }
1512 174206 : else if (IsA(node, FuncExpr))
1513 : {
1514 6707 : FuncExpr *expr = (FuncExpr *) node;
1515 :
1516 6707 : if (func_strict(expr->funcid))
1517 6553 : result = find_nonnullable_rels_walker((Node *) expr->args, false);
1518 : }
1519 167499 : else if (IsA(node, OpExpr))
1520 : {
1521 97630 : OpExpr *expr = (OpExpr *) node;
1522 :
1523 97630 : set_opfuncid(expr);
1524 97630 : if (func_strict(expr->opfuncid))
1525 97630 : result = find_nonnullable_rels_walker((Node *) expr->args, false);
1526 : }
1527 69869 : else if (IsA(node, ScalarArrayOpExpr))
1528 : {
1529 6375 : ScalarArrayOpExpr *expr = (ScalarArrayOpExpr *) node;
1530 :
1531 6375 : if (is_strict_saop(expr, true))
1532 6375 : result = find_nonnullable_rels_walker((Node *) expr->args, false);
1533 : }
1534 63494 : else if (IsA(node, BoolExpr))
1535 : {
1536 7234 : BoolExpr *expr = (BoolExpr *) node;
1537 :
1538 7234 : switch (expr->boolop)
1539 : {
1540 329 : case AND_EXPR:
1541 : /* At top level we can just recurse (to the List case) */
1542 329 : if (top_level)
1543 : {
1544 329 : result = find_nonnullable_rels_walker((Node *) expr->args,
1545 : top_level);
1546 329 : break;
1547 : }
1548 :
1549 : /*
1550 : * Below top level, even if one arm produces NULL, the result
1551 : * could be FALSE (hence not NULL). However, if *all* the
1552 : * arms produce NULL then the result is NULL, so we can take
1553 : * the intersection of the sets of nonnullable rels, just as
1554 : * for OR. Fall through to share code.
1555 : */
1556 : pg_fallthrough;
1557 : case OR_EXPR:
1558 :
1559 : /*
1560 : * OR is strict if all of its arms are, so we can take the
1561 : * intersection of the sets of nonnullable rels for each arm.
1562 : * This works for both values of top_level.
1563 : */
1564 9181 : foreach(l, expr->args)
1565 : {
1566 : Relids subresult;
1567 :
1568 7405 : subresult = find_nonnullable_rels_walker(lfirst(l),
1569 : top_level);
1570 7405 : if (result == NULL) /* first subresult? */
1571 3722 : result = subresult;
1572 : else
1573 3683 : result = bms_int_members(result, subresult);
1574 :
1575 : /*
1576 : * If the intersection is empty, we can stop looking. This
1577 : * also justifies the test for first-subresult above.
1578 : */
1579 7405 : if (bms_is_empty(result))
1580 1946 : break;
1581 : }
1582 3722 : break;
1583 3183 : case NOT_EXPR:
1584 : /* NOT will return null if its arg is null */
1585 3183 : result = find_nonnullable_rels_walker((Node *) expr->args,
1586 : false);
1587 3183 : break;
1588 0 : default:
1589 0 : elog(ERROR, "unrecognized boolop: %d", (int) expr->boolop);
1590 : break;
1591 : }
1592 : }
1593 56260 : else if (IsA(node, RelabelType))
1594 : {
1595 3439 : RelabelType *expr = (RelabelType *) node;
1596 :
1597 3439 : result = find_nonnullable_rels_walker((Node *) expr->arg, top_level);
1598 : }
1599 52821 : else if (IsA(node, CoerceViaIO))
1600 : {
1601 : /* not clear this is useful, but it can't hurt */
1602 177 : CoerceViaIO *expr = (CoerceViaIO *) node;
1603 :
1604 177 : result = find_nonnullable_rels_walker((Node *) expr->arg, top_level);
1605 : }
1606 52644 : else if (IsA(node, ArrayCoerceExpr))
1607 : {
1608 : /* ArrayCoerceExpr is strict at the array level; ignore elemexpr */
1609 0 : ArrayCoerceExpr *expr = (ArrayCoerceExpr *) node;
1610 :
1611 0 : result = find_nonnullable_rels_walker((Node *) expr->arg, top_level);
1612 : }
1613 52644 : else if (IsA(node, ConvertRowtypeExpr))
1614 : {
1615 : /* not clear this is useful, but it can't hurt */
1616 0 : ConvertRowtypeExpr *expr = (ConvertRowtypeExpr *) node;
1617 :
1618 0 : result = find_nonnullable_rels_walker((Node *) expr->arg, top_level);
1619 : }
1620 52644 : else if (IsA(node, CollateExpr))
1621 : {
1622 0 : CollateExpr *expr = (CollateExpr *) node;
1623 :
1624 0 : result = find_nonnullable_rels_walker((Node *) expr->arg, top_level);
1625 : }
1626 52644 : else if (IsA(node, NullTest))
1627 : {
1628 : /* IS NOT NULL can be considered strict, but only at top level */
1629 4275 : NullTest *expr = (NullTest *) node;
1630 :
1631 4275 : if (top_level && expr->nulltesttype == IS_NOT_NULL && !expr->argisrow)
1632 2818 : result = find_nonnullable_rels_walker((Node *) expr->arg, false);
1633 : }
1634 48369 : else if (IsA(node, BooleanTest))
1635 : {
1636 : /* Boolean tests that reject NULL are strict at top level */
1637 109 : BooleanTest *expr = (BooleanTest *) node;
1638 :
1639 109 : if (top_level &&
1640 109 : (expr->booltesttype == IS_TRUE ||
1641 109 : expr->booltesttype == IS_FALSE ||
1642 5 : expr->booltesttype == IS_NOT_UNKNOWN))
1643 104 : result = find_nonnullable_rels_walker((Node *) expr->arg, false);
1644 : }
1645 48260 : else if (IsA(node, SubPlan))
1646 : {
1647 108 : SubPlan *splan = (SubPlan *) node;
1648 :
1649 : /*
1650 : * For some types of SubPlan, we can infer strictness from Vars in the
1651 : * testexpr (the LHS of the original SubLink).
1652 : *
1653 : * For ANY_SUBLINK, if the subquery produces zero rows, the result is
1654 : * always FALSE. If the subquery produces more than one row, the
1655 : * per-row results of the testexpr are combined using OR semantics.
1656 : * Hence ANY_SUBLINK can be strict only at top level, but there it's
1657 : * as strict as the testexpr is.
1658 : *
1659 : * For ROWCOMPARE_SUBLINK, if the subquery produces zero rows, the
1660 : * result is always NULL. Otherwise, the result is as strict as the
1661 : * testexpr is. So we can check regardless of top_level.
1662 : *
1663 : * We can't prove anything for other sublink types (in particular,
1664 : * note that ALL_SUBLINK will return TRUE if the subquery is empty).
1665 : */
1666 108 : if ((top_level && splan->subLinkType == ANY_SUBLINK) ||
1667 73 : splan->subLinkType == ROWCOMPARE_SUBLINK)
1668 35 : result = find_nonnullable_rels_walker(splan->testexpr, top_level);
1669 : }
1670 48152 : else if (IsA(node, PlaceHolderVar))
1671 : {
1672 440 : PlaceHolderVar *phv = (PlaceHolderVar *) node;
1673 :
1674 : /*
1675 : * If the contained expression forces any rels non-nullable, so does
1676 : * the PHV.
1677 : */
1678 440 : result = find_nonnullable_rels_walker((Node *) phv->phexpr, top_level);
1679 :
1680 : /*
1681 : * If the PHV's syntactic scope is exactly one rel, it will be forced
1682 : * to be evaluated at that rel, and so it will behave like a Var of
1683 : * that rel: if the rel's entire output goes to null, so will the PHV.
1684 : * (If the syntactic scope is a join, we know that the PHV will go to
1685 : * null if the whole join does; but that is AND semantics while we
1686 : * need OR semantics for find_nonnullable_rels' result, so we can't do
1687 : * anything with the knowledge.)
1688 : */
1689 880 : if (phv->phlevelsup == 0 &&
1690 440 : bms_membership(phv->phrels) == BMS_SINGLETON)
1691 280 : result = bms_add_members(result, phv->phrels);
1692 : }
1693 538671 : return result;
1694 : }
1695 :
1696 : /*
1697 : * find_nonnullable_vars
1698 : * Determine which Vars are forced nonnullable by given clause.
1699 : *
1700 : * Returns the set of all level-zero Vars that are referenced in the clause in
1701 : * such a way that the clause cannot possibly return TRUE if any of these Vars
1702 : * is NULL. (It is OK to err on the side of conservatism; hence the analysis
1703 : * here is simplistic.)
1704 : *
1705 : * The semantics here are subtly different from contain_nonstrict_functions:
1706 : * that function is concerned with NULL results from arbitrary expressions,
1707 : * but here we assume that the input is a Boolean expression, and wish to
1708 : * see if NULL inputs will provably cause a FALSE-or-NULL result. We expect
1709 : * the expression to have been AND/OR flattened and converted to implicit-AND
1710 : * format (but the results are still good if it wasn't AND/OR flattened).
1711 : *
1712 : * Attnos of the identified Vars are returned in a multibitmapset (a List of
1713 : * Bitmapsets). List indexes correspond to relids (varnos), while the per-rel
1714 : * Bitmapsets hold varattnos offset by FirstLowInvalidHeapAttributeNumber.
1715 : *
1716 : * top_level is true while scanning top-level AND/OR structure; here, showing
1717 : * the result is either FALSE or NULL is good enough. top_level is false when
1718 : * we have descended below a NOT or a strict function: now we must be able to
1719 : * prove that the subexpression goes to NULL.
1720 : *
1721 : * We don't use expression_tree_walker here because we don't want to descend
1722 : * through very many kinds of nodes; only the ones we can be sure are strict.
1723 : */
1724 : List *
1725 1160 : find_nonnullable_vars(Node *clause)
1726 : {
1727 1160 : return find_nonnullable_vars_walker(clause, true);
1728 : }
1729 :
1730 : static List *
1731 7713 : find_nonnullable_vars_walker(Node *node, bool top_level)
1732 : {
1733 7713 : List *result = NIL;
1734 : ListCell *l;
1735 :
1736 7713 : if (node == NULL)
1737 25 : return NIL;
1738 7688 : if (IsA(node, Var))
1739 : {
1740 3038 : Var *var = (Var *) node;
1741 :
1742 3038 : if (var->varlevelsup == 0)
1743 3038 : result = mbms_add_member(result,
1744 : var->varno,
1745 3038 : var->varattno - FirstLowInvalidHeapAttributeNumber);
1746 : }
1747 4650 : else if (IsA(node, List))
1748 : {
1749 : /*
1750 : * At top level, we are examining an implicit-AND list: if any of the
1751 : * arms produces FALSE-or-NULL then the result is FALSE-or-NULL. If
1752 : * not at top level, we are examining the arguments of a strict
1753 : * function: if any of them produce NULL then the result of the
1754 : * function must be NULL. So in both cases, the set of nonnullable
1755 : * vars is the union of those found in the arms, and we pass down the
1756 : * top_level flag unmodified.
1757 : */
1758 7435 : foreach(l, (List *) node)
1759 : {
1760 4712 : result = mbms_add_members(result,
1761 4712 : find_nonnullable_vars_walker(lfirst(l),
1762 : top_level));
1763 : }
1764 : }
1765 1927 : else if (IsA(node, FuncExpr))
1766 : {
1767 10 : FuncExpr *expr = (FuncExpr *) node;
1768 :
1769 10 : if (func_strict(expr->funcid))
1770 10 : result = find_nonnullable_vars_walker((Node *) expr->args, false);
1771 : }
1772 1917 : else if (IsA(node, OpExpr))
1773 : {
1774 1558 : OpExpr *expr = (OpExpr *) node;
1775 :
1776 1558 : set_opfuncid(expr);
1777 1558 : if (func_strict(expr->opfuncid))
1778 1558 : result = find_nonnullable_vars_walker((Node *) expr->args, false);
1779 : }
1780 359 : else if (IsA(node, ScalarArrayOpExpr))
1781 : {
1782 0 : ScalarArrayOpExpr *expr = (ScalarArrayOpExpr *) node;
1783 :
1784 0 : if (is_strict_saop(expr, true))
1785 0 : result = find_nonnullable_vars_walker((Node *) expr->args, false);
1786 : }
1787 359 : else if (IsA(node, BoolExpr))
1788 : {
1789 98 : BoolExpr *expr = (BoolExpr *) node;
1790 :
1791 98 : switch (expr->boolop)
1792 : {
1793 0 : case AND_EXPR:
1794 :
1795 : /*
1796 : * At top level we can just recurse (to the List case), since
1797 : * the result should be the union of what we can prove in each
1798 : * arm.
1799 : */
1800 0 : if (top_level)
1801 : {
1802 0 : result = find_nonnullable_vars_walker((Node *) expr->args,
1803 : top_level);
1804 0 : break;
1805 : }
1806 :
1807 : /*
1808 : * Below top level, even if one arm produces NULL, the result
1809 : * could be FALSE (hence not NULL). However, if *all* the
1810 : * arms produce NULL then the result is NULL, so we can take
1811 : * the intersection of the sets of nonnullable vars, just as
1812 : * for OR. Fall through to share code.
1813 : */
1814 : pg_fallthrough;
1815 : case OR_EXPR:
1816 :
1817 : /*
1818 : * OR is strict if all of its arms are, so we can take the
1819 : * intersection of the sets of nonnullable vars for each arm.
1820 : * This works for both values of top_level.
1821 : */
1822 176 : foreach(l, expr->args)
1823 : {
1824 : List *subresult;
1825 :
1826 176 : subresult = find_nonnullable_vars_walker(lfirst(l),
1827 : top_level);
1828 176 : if (result == NIL) /* first subresult? */
1829 78 : result = subresult;
1830 : else
1831 98 : result = mbms_int_members(result, subresult);
1832 :
1833 : /*
1834 : * If the intersection is empty, we can stop looking. This
1835 : * also justifies the test for first-subresult above.
1836 : */
1837 176 : if (result == NIL)
1838 78 : break;
1839 : }
1840 78 : break;
1841 20 : case NOT_EXPR:
1842 : /* NOT will return null if its arg is null */
1843 20 : result = find_nonnullable_vars_walker((Node *) expr->args,
1844 : false);
1845 20 : break;
1846 0 : default:
1847 0 : elog(ERROR, "unrecognized boolop: %d", (int) expr->boolop);
1848 : break;
1849 : }
1850 : }
1851 261 : else if (IsA(node, RelabelType))
1852 : {
1853 46 : RelabelType *expr = (RelabelType *) node;
1854 :
1855 46 : result = find_nonnullable_vars_walker((Node *) expr->arg, top_level);
1856 : }
1857 215 : else if (IsA(node, CoerceViaIO))
1858 : {
1859 : /* not clear this is useful, but it can't hurt */
1860 16 : CoerceViaIO *expr = (CoerceViaIO *) node;
1861 :
1862 16 : result = find_nonnullable_vars_walker((Node *) expr->arg, false);
1863 : }
1864 199 : else if (IsA(node, ArrayCoerceExpr))
1865 : {
1866 : /* ArrayCoerceExpr is strict at the array level; ignore elemexpr */
1867 0 : ArrayCoerceExpr *expr = (ArrayCoerceExpr *) node;
1868 :
1869 0 : result = find_nonnullable_vars_walker((Node *) expr->arg, top_level);
1870 : }
1871 199 : else if (IsA(node, ConvertRowtypeExpr))
1872 : {
1873 : /* not clear this is useful, but it can't hurt */
1874 0 : ConvertRowtypeExpr *expr = (ConvertRowtypeExpr *) node;
1875 :
1876 0 : result = find_nonnullable_vars_walker((Node *) expr->arg, top_level);
1877 : }
1878 199 : else if (IsA(node, CollateExpr))
1879 : {
1880 0 : CollateExpr *expr = (CollateExpr *) node;
1881 :
1882 0 : result = find_nonnullable_vars_walker((Node *) expr->arg, top_level);
1883 : }
1884 199 : else if (IsA(node, NullTest))
1885 : {
1886 : /* IS NOT NULL can be considered strict, but only at top level */
1887 93 : NullTest *expr = (NullTest *) node;
1888 :
1889 93 : if (top_level && expr->nulltesttype == IS_NOT_NULL && !expr->argisrow)
1890 15 : result = find_nonnullable_vars_walker((Node *) expr->arg, false);
1891 : }
1892 106 : else if (IsA(node, BooleanTest))
1893 : {
1894 : /* Boolean tests that reject NULL are strict at top level */
1895 0 : BooleanTest *expr = (BooleanTest *) node;
1896 :
1897 0 : if (top_level &&
1898 0 : (expr->booltesttype == IS_TRUE ||
1899 0 : expr->booltesttype == IS_FALSE ||
1900 0 : expr->booltesttype == IS_NOT_UNKNOWN))
1901 0 : result = find_nonnullable_vars_walker((Node *) expr->arg, false);
1902 : }
1903 106 : else if (IsA(node, SubPlan))
1904 : {
1905 0 : SubPlan *splan = (SubPlan *) node;
1906 :
1907 : /* See analysis in find_nonnullable_rels_walker */
1908 0 : if ((top_level && splan->subLinkType == ANY_SUBLINK) ||
1909 0 : splan->subLinkType == ROWCOMPARE_SUBLINK)
1910 0 : result = find_nonnullable_vars_walker(splan->testexpr, top_level);
1911 : }
1912 106 : else if (IsA(node, PlaceHolderVar))
1913 : {
1914 0 : PlaceHolderVar *phv = (PlaceHolderVar *) node;
1915 :
1916 0 : result = find_nonnullable_vars_walker((Node *) phv->phexpr, top_level);
1917 : }
1918 7688 : return result;
1919 : }
1920 :
1921 : /*
1922 : * find_forced_null_vars
1923 : * Determine which Vars must be NULL for the given clause to return TRUE.
1924 : *
1925 : * This is the complement of find_nonnullable_vars: find the level-zero Vars
1926 : * that must be NULL for the clause to return TRUE. (It is OK to err on the
1927 : * side of conservatism; hence the analysis here is simplistic. In fact,
1928 : * we only detect simple "var IS NULL" tests at the top level.)
1929 : *
1930 : * As with find_nonnullable_vars, we return the varattnos of the identified
1931 : * Vars in a multibitmapset.
1932 : */
1933 : List *
1934 93887 : find_forced_null_vars(Node *node)
1935 : {
1936 93887 : List *result = NIL;
1937 : Var *var;
1938 : ListCell *l;
1939 :
1940 93887 : if (node == NULL)
1941 4362 : return NIL;
1942 : /* Check single-clause cases using subroutine */
1943 89525 : var = find_forced_null_var(node);
1944 89525 : if (var)
1945 : {
1946 1156 : result = mbms_add_member(result,
1947 : var->varno,
1948 1156 : var->varattno - FirstLowInvalidHeapAttributeNumber);
1949 : }
1950 : /* Otherwise, handle AND-conditions */
1951 88369 : else if (IsA(node, List))
1952 : {
1953 : /*
1954 : * At top level, we are examining an implicit-AND list: if any of the
1955 : * arms produces FALSE-or-NULL then the result is FALSE-or-NULL.
1956 : */
1957 89525 : foreach(l, (List *) node)
1958 : {
1959 54698 : result = mbms_add_members(result,
1960 54698 : find_forced_null_vars((Node *) lfirst(l)));
1961 : }
1962 : }
1963 53542 : else if (IsA(node, BoolExpr))
1964 : {
1965 4355 : BoolExpr *expr = (BoolExpr *) node;
1966 :
1967 : /*
1968 : * We don't bother considering the OR case, because it's fairly
1969 : * unlikely anyone would write "v1 IS NULL OR v1 IS NULL". Likewise,
1970 : * the NOT case isn't worth expending code on.
1971 : */
1972 4355 : if (expr->boolop == AND_EXPR)
1973 : {
1974 : /* At top level we can just recurse (to the List case) */
1975 0 : result = find_forced_null_vars((Node *) expr->args);
1976 : }
1977 : }
1978 89525 : return result;
1979 : }
1980 :
1981 : /*
1982 : * find_forced_null_var
1983 : * Return the Var forced null by the given clause, or NULL if it's
1984 : * not an IS NULL-type clause. For success, the clause must enforce
1985 : * *only* nullness of the particular Var, not any other conditions.
1986 : *
1987 : * This is just the single-clause case of find_forced_null_vars(), without
1988 : * any allowance for AND conditions. It's used by initsplan.c on individual
1989 : * qual clauses. The reason for not just applying find_forced_null_vars()
1990 : * is that if an AND of an IS NULL clause with something else were to somehow
1991 : * survive AND/OR flattening, initsplan.c might get fooled into discarding
1992 : * the whole clause when only the IS NULL part of it had been proved redundant.
1993 : */
1994 : Var *
1995 473406 : find_forced_null_var(Node *node)
1996 : {
1997 473406 : if (node == NULL)
1998 0 : return NULL;
1999 473406 : if (IsA(node, NullTest))
2000 : {
2001 : /* check for var IS NULL */
2002 9493 : NullTest *expr = (NullTest *) node;
2003 :
2004 9493 : if (expr->nulltesttype == IS_NULL && !expr->argisrow)
2005 : {
2006 3501 : Var *var = (Var *) expr->arg;
2007 :
2008 3501 : if (var && IsA(var, Var) &&
2009 3403 : var->varlevelsup == 0)
2010 3403 : return var;
2011 : }
2012 : }
2013 463913 : else if (IsA(node, BooleanTest))
2014 : {
2015 : /* var IS UNKNOWN is equivalent to var IS NULL */
2016 560 : BooleanTest *expr = (BooleanTest *) node;
2017 :
2018 560 : if (expr->booltesttype == IS_UNKNOWN)
2019 : {
2020 45 : Var *var = (Var *) expr->arg;
2021 :
2022 45 : if (var && IsA(var, Var) &&
2023 45 : var->varlevelsup == 0)
2024 45 : return var;
2025 : }
2026 : }
2027 469958 : return NULL;
2028 : }
2029 :
2030 : /*
2031 : * query_outputs_are_not_nullable
2032 : * Returns TRUE if the output values of the Query are certainly not NULL.
2033 : * All output columns must return non-NULL to answer TRUE.
2034 : *
2035 : * The reason this takes a Query, and not just an individual tlist expression,
2036 : * is so that we can make use of the query's WHERE/ON clauses to prove it does
2037 : * not return nulls.
2038 : *
2039 : * In current usage, the passed sub-Query hasn't yet been through any planner
2040 : * processing. This means that applying find_nonnullable_vars() to its WHERE
2041 : * clauses isn't really ideal: for lack of const-simplification, we might be
2042 : * unable to prove not-nullness in some cases where we could have proved it
2043 : * afterwards. However, we should not get any false positive results.
2044 : *
2045 : * Like the other forms of nullability analysis above, we can err on the
2046 : * side of conservatism: if we're not sure, it's okay to return FALSE.
2047 : */
2048 : bool
2049 110 : query_outputs_are_not_nullable(Query *query)
2050 : {
2051 : PlannerInfo subroot;
2052 110 : List *safe_quals = NIL;
2053 110 : List *nonnullable_vars = NIL;
2054 110 : bool computed_nonnullable_vars = false;
2055 :
2056 : /*
2057 : * If the query contains set operations, punt. The set ops themselves
2058 : * couldn't introduce nulls that weren't in their inputs, but the tlist
2059 : * present in the top-level query is just dummy and won't give us useful
2060 : * info. We could get an answer by recursing to examine each leaf query,
2061 : * but for the moment it doesn't seem worth the extra complication.
2062 : */
2063 110 : if (query->setOperations)
2064 0 : return false;
2065 :
2066 : /*
2067 : * If the query contains grouping sets, punt. Grouping sets can introduce
2068 : * NULL values, and we currently lack the PlannerInfo needed to flatten
2069 : * grouping Vars in the query's outputs.
2070 : */
2071 110 : if (query->groupingSets)
2072 5 : return false;
2073 :
2074 : /*
2075 : * We need a PlannerInfo to pass to expr_is_nonnullable. Fortunately, we
2076 : * can cons up an entirely dummy one, because only the "parse" link in the
2077 : * struct is used by expr_is_nonnullable.
2078 : */
2079 9870 : MemSet(&subroot, 0, sizeof(subroot));
2080 105 : subroot.parse = query;
2081 :
2082 : /*
2083 : * Examine each targetlist entry to prove that it can't produce NULL.
2084 : */
2085 290 : foreach_node(TargetEntry, tle, query->targetList)
2086 : {
2087 120 : Expr *expr = tle->expr;
2088 :
2089 : /* Resjunk columns can be ignored: they don't produce output values */
2090 120 : if (tle->resjunk)
2091 0 : continue;
2092 :
2093 : /*
2094 : * Look through binary relabelings, since we know those don't
2095 : * introduce nulls.
2096 : */
2097 120 : while (expr && IsA(expr, RelabelType))
2098 0 : expr = ((RelabelType *) expr)->arg;
2099 :
2100 120 : if (expr == NULL) /* paranoia */
2101 20 : return false;
2102 :
2103 : /*
2104 : * Since the subquery hasn't yet been through expression
2105 : * preprocessing, we must explicitly flatten grouping Vars and join
2106 : * alias Vars in the given expression. Note that flatten_group_exprs
2107 : * must be applied before flatten_join_alias_vars, as grouping Vars
2108 : * can wrap join alias Vars.
2109 : *
2110 : * We must also apply flatten_join_alias_vars to the quals extracted
2111 : * by find_subquery_safe_quals. We do not need to apply
2112 : * flatten_group_exprs to these quals, though, because grouping Vars
2113 : * cannot appear in jointree quals.
2114 : */
2115 :
2116 : /*
2117 : * We have verified that the query does not contain grouping sets,
2118 : * meaning the grouping Vars will not have varnullingrels that need
2119 : * preserving, so it's safe to use NULL as the root here.
2120 : */
2121 120 : if (query->hasGroupRTE)
2122 10 : expr = (Expr *) flatten_group_exprs(NULL, query, (Node *) expr);
2123 :
2124 : /*
2125 : * We won't be dealing with arbitrary expressions, so it's safe to use
2126 : * NULL as the root, so long as adjust_standard_join_alias_expression
2127 : * can handle everything the parser would make as a join alias
2128 : * expression.
2129 : */
2130 120 : expr = (Expr *) flatten_join_alias_vars(NULL, query, (Node *) expr);
2131 :
2132 : /*
2133 : * Check to see if the expr cannot be NULL. Since we're on a raw
2134 : * parse tree, we need to look up the not-null constraints from the
2135 : * system catalogs.
2136 : */
2137 120 : if (expr_is_nonnullable(&subroot, expr, NOTNULL_SOURCE_SYSCACHE))
2138 80 : continue;
2139 :
2140 40 : if (IsA(expr, Var))
2141 : {
2142 40 : Var *var = (Var *) expr;
2143 :
2144 : /*
2145 : * For a plain Var, even if that didn't work, we can conclude that
2146 : * the Var is not nullable if find_nonnullable_vars can find a
2147 : * "var IS NOT NULL" or similarly strict condition among the quals
2148 : * on non-outerjoined-rels. Compute the list of Vars having such
2149 : * quals if we didn't already.
2150 : */
2151 40 : if (!computed_nonnullable_vars)
2152 : {
2153 40 : find_subquery_safe_quals((Node *) query->jointree, &safe_quals);
2154 40 : safe_quals = (List *)
2155 40 : flatten_join_alias_vars(NULL, query, (Node *) safe_quals);
2156 40 : nonnullable_vars = find_nonnullable_vars((Node *) safe_quals);
2157 40 : computed_nonnullable_vars = true;
2158 : }
2159 :
2160 40 : if (!mbms_is_member(var->varno,
2161 40 : var->varattno - FirstLowInvalidHeapAttributeNumber,
2162 : nonnullable_vars))
2163 20 : return false; /* we failed to prove the Var non-null */
2164 : }
2165 : else
2166 : {
2167 : /* Punt otherwise */
2168 0 : return false;
2169 : }
2170 : }
2171 :
2172 85 : return true;
2173 : }
2174 :
2175 : /*
2176 : * find_subquery_safe_quals
2177 : * Traverse jointree to locate quals on non-outerjoined-rels.
2178 : *
2179 : * We locate all WHERE and JOIN/ON quals that constrain the rels that are not
2180 : * below the nullable side of any outer join, and add them to the *safe_quals
2181 : * list (forming a list with implicit-AND semantics). These quals can be used
2182 : * to prove non-nullability of the subquery's outputs.
2183 : *
2184 : * Top-level caller must initialize *safe_quals to NIL.
2185 : */
2186 : static void
2187 115 : find_subquery_safe_quals(Node *jtnode, List **safe_quals)
2188 : {
2189 115 : if (jtnode == NULL)
2190 0 : return;
2191 115 : if (IsA(jtnode, RangeTblRef))
2192 : {
2193 : /* Leaf node: nothing to do */
2194 50 : return;
2195 : }
2196 65 : else if (IsA(jtnode, FromExpr))
2197 : {
2198 40 : FromExpr *f = (FromExpr *) jtnode;
2199 :
2200 : /* All elements of the FROM list are allowable */
2201 125 : foreach_ptr(Node, child_node, f->fromlist)
2202 45 : find_subquery_safe_quals(child_node, safe_quals);
2203 : /* ... and its WHERE quals are too */
2204 40 : if (f->quals)
2205 15 : *safe_quals = lappend(*safe_quals, f->quals);
2206 : }
2207 25 : else if (IsA(jtnode, JoinExpr))
2208 : {
2209 25 : JoinExpr *j = (JoinExpr *) jtnode;
2210 :
2211 25 : switch (j->jointype)
2212 : {
2213 5 : case JOIN_INNER:
2214 : /* visit both children */
2215 5 : find_subquery_safe_quals(j->larg, safe_quals);
2216 5 : find_subquery_safe_quals(j->rarg, safe_quals);
2217 : /* and grab the ON quals too */
2218 5 : if (j->quals)
2219 5 : *safe_quals = lappend(*safe_quals, j->quals);
2220 5 : break;
2221 :
2222 20 : case JOIN_LEFT:
2223 : case JOIN_SEMI:
2224 : case JOIN_ANTI:
2225 :
2226 : /*
2227 : * Only the left input is possibly non-nullable; furthermore,
2228 : * the quals of this join don't constrain the left input.
2229 : * Note: we probably can't see SEMI or ANTI joins at this
2230 : * point, but if we do, we can treat them like LEFT joins.
2231 : */
2232 20 : find_subquery_safe_quals(j->larg, safe_quals);
2233 20 : break;
2234 :
2235 0 : case JOIN_RIGHT:
2236 : /* Reverse of the above case */
2237 0 : find_subquery_safe_quals(j->rarg, safe_quals);
2238 0 : break;
2239 :
2240 0 : case JOIN_FULL:
2241 : /* Neither side is non-nullable, so stop descending */
2242 0 : break;
2243 :
2244 0 : default:
2245 0 : elog(ERROR, "unrecognized join type: %d",
2246 : (int) j->jointype);
2247 : break;
2248 : }
2249 : }
2250 : else
2251 0 : elog(ERROR, "unrecognized node type: %d",
2252 : (int) nodeTag(jtnode));
2253 : }
2254 :
2255 : /*
2256 : * Can we treat a ScalarArrayOpExpr as strict?
2257 : *
2258 : * If "falseOK" is true, then a "false" result can be considered strict,
2259 : * else we need to guarantee an actual NULL result for NULL input.
2260 : *
2261 : * "foo op ALL array" is strict if the op is strict *and* we can prove
2262 : * that the array input isn't an empty array. We can check that
2263 : * for the cases of an array constant and an ARRAY[] construct.
2264 : *
2265 : * "foo op ANY array" is strict in the falseOK sense if the op is strict.
2266 : * If not falseOK, the test is the same as for "foo op ALL array".
2267 : */
2268 : static bool
2269 6375 : is_strict_saop(ScalarArrayOpExpr *expr, bool falseOK)
2270 : {
2271 : Node *rightop;
2272 :
2273 : /* The contained operator must be strict. */
2274 6375 : set_sa_opfuncid(expr);
2275 6375 : if (!func_strict(expr->opfuncid))
2276 0 : return false;
2277 : /* If ANY and falseOK, that's all we need to check. */
2278 6375 : if (expr->useOr && falseOK)
2279 6262 : return true;
2280 : /* Else, we have to see if the array is provably non-empty. */
2281 : Assert(list_length(expr->args) == 2);
2282 113 : rightop = (Node *) lsecond(expr->args);
2283 113 : if (rightop && IsA(rightop, Const))
2284 0 : {
2285 113 : Datum arraydatum = ((Const *) rightop)->constvalue;
2286 113 : bool arrayisnull = ((Const *) rightop)->constisnull;
2287 : ArrayType *arrayval;
2288 : int nitems;
2289 :
2290 113 : if (arrayisnull)
2291 0 : return false;
2292 113 : arrayval = DatumGetArrayTypeP(arraydatum);
2293 113 : nitems = ArrayGetNItems(ARR_NDIM(arrayval), ARR_DIMS(arrayval));
2294 113 : if (nitems > 0)
2295 113 : return true;
2296 : }
2297 0 : else if (rightop && IsA(rightop, ArrayExpr))
2298 : {
2299 0 : ArrayExpr *arrayexpr = (ArrayExpr *) rightop;
2300 :
2301 0 : if (arrayexpr->elements != NIL && !arrayexpr->multidims)
2302 0 : return true;
2303 : }
2304 0 : return false;
2305 : }
2306 :
2307 :
2308 : /*****************************************************************************
2309 : * Check for "pseudo-constant" clauses
2310 : *****************************************************************************/
2311 :
2312 : /*
2313 : * is_pseudo_constant_clause
2314 : * Detect whether an expression is "pseudo constant", ie, it contains no
2315 : * variables of the current query level and no uses of volatile functions.
2316 : * Such an expr is not necessarily a true constant: it can still contain
2317 : * Params and outer-level Vars, not to mention functions whose results
2318 : * may vary from one statement to the next. However, the expr's value
2319 : * will be constant over any one scan of the current query, so it can be
2320 : * used as, eg, an indexscan key. (Actually, the condition for indexscan
2321 : * keys is weaker than this; see is_pseudo_constant_for_index().)
2322 : *
2323 : * CAUTION: this function omits to test for one very important class of
2324 : * not-constant expressions, namely aggregates (Aggrefs). In current usage
2325 : * this is only applied to WHERE clauses and so a check for Aggrefs would be
2326 : * a waste of cycles; but be sure to also check contain_agg_clause() if you
2327 : * want to know about pseudo-constness in other contexts. The same goes
2328 : * for window functions (WindowFuncs).
2329 : */
2330 : bool
2331 4772 : is_pseudo_constant_clause(Node *clause)
2332 : {
2333 : /*
2334 : * We could implement this check in one recursive scan. But since the
2335 : * check for volatile functions is both moderately expensive and unlikely
2336 : * to fail, it seems better to look for Vars first and only check for
2337 : * volatile functions if we find no Vars.
2338 : */
2339 4772 : if (!contain_var_clause(clause) &&
2340 4772 : !contain_volatile_functions(clause))
2341 4772 : return true;
2342 0 : return false;
2343 : }
2344 :
2345 : /*
2346 : * is_pseudo_constant_clause_relids
2347 : * Same as above, except caller already has available the var membership
2348 : * of the expression; this lets us avoid the contain_var_clause() scan.
2349 : */
2350 : bool
2351 353094 : is_pseudo_constant_clause_relids(Node *clause, Relids relids)
2352 : {
2353 353094 : if (bms_is_empty(relids) &&
2354 346629 : !contain_volatile_functions(clause))
2355 346629 : return true;
2356 6465 : return false;
2357 : }
2358 :
2359 :
2360 : /*****************************************************************************
2361 : * *
2362 : * General clause-manipulating routines *
2363 : * *
2364 : *****************************************************************************/
2365 :
2366 : /*
2367 : * NumRelids
2368 : * (formerly clause_relids)
2369 : *
2370 : * Returns the number of different base relations referenced in 'clause'.
2371 : */
2372 : int
2373 1407 : NumRelids(PlannerInfo *root, Node *clause)
2374 : {
2375 : int result;
2376 1407 : Relids varnos = pull_varnos(root, clause);
2377 :
2378 1407 : varnos = bms_del_members(varnos, root->outer_join_rels);
2379 1407 : result = bms_num_members(varnos);
2380 1407 : bms_free(varnos);
2381 1407 : return result;
2382 : }
2383 :
2384 : /*
2385 : * CommuteOpExpr: commute a binary operator clause
2386 : *
2387 : * XXX the clause is destructively modified!
2388 : */
2389 : void
2390 18781 : CommuteOpExpr(OpExpr *clause)
2391 : {
2392 : Oid opoid;
2393 : Node *temp;
2394 :
2395 : /* Sanity checks: caller is at fault if these fail */
2396 37562 : if (!is_opclause(clause) ||
2397 18781 : list_length(clause->args) != 2)
2398 0 : elog(ERROR, "cannot commute non-binary-operator clause");
2399 :
2400 18781 : opoid = get_commutator(clause->opno);
2401 :
2402 18781 : if (!OidIsValid(opoid))
2403 0 : elog(ERROR, "could not find commutator for operator %u",
2404 : clause->opno);
2405 :
2406 : /*
2407 : * modify the clause in-place!
2408 : */
2409 18781 : clause->opno = opoid;
2410 18781 : clause->opfuncid = InvalidOid;
2411 : /* opresulttype, opretset, opcollid, inputcollid need not change */
2412 :
2413 18781 : temp = linitial(clause->args);
2414 18781 : linitial(clause->args) = lsecond(clause->args);
2415 18781 : lsecond(clause->args) = temp;
2416 18781 : }
2417 :
2418 : /*
2419 : * Helper for eval_const_expressions: check that datatype of an attribute
2420 : * is still what it was when the expression was parsed. This is needed to
2421 : * guard against improper simplification after ALTER COLUMN TYPE. (XXX we
2422 : * may well need to make similar checks elsewhere?)
2423 : *
2424 : * rowtypeid may come from a whole-row Var, and therefore it can be a domain
2425 : * over composite, but for this purpose we only care about checking the type
2426 : * of a contained field.
2427 : */
2428 : static bool
2429 594 : rowtype_field_matches(Oid rowtypeid, int fieldnum,
2430 : Oid expectedtype, int32 expectedtypmod,
2431 : Oid expectedcollation)
2432 : {
2433 : TupleDesc tupdesc;
2434 : Form_pg_attribute attr;
2435 :
2436 : /* No issue for RECORD, since there is no way to ALTER such a type */
2437 594 : if (rowtypeid == RECORDOID)
2438 42 : return true;
2439 552 : tupdesc = lookup_rowtype_tupdesc_domain(rowtypeid, -1, false);
2440 552 : if (fieldnum <= 0 || fieldnum > tupdesc->natts)
2441 : {
2442 0 : ReleaseTupleDesc(tupdesc);
2443 0 : return false;
2444 : }
2445 552 : attr = TupleDescAttr(tupdesc, fieldnum - 1);
2446 552 : if (attr->attisdropped ||
2447 552 : attr->atttypid != expectedtype ||
2448 552 : attr->atttypmod != expectedtypmod ||
2449 552 : attr->attcollation != expectedcollation)
2450 : {
2451 0 : ReleaseTupleDesc(tupdesc);
2452 0 : return false;
2453 : }
2454 552 : ReleaseTupleDesc(tupdesc);
2455 552 : return true;
2456 : }
2457 :
2458 :
2459 : /*--------------------
2460 : * eval_const_expressions
2461 : *
2462 : * Reduce any recognizably constant subexpressions of the given
2463 : * expression tree, for example "2 + 2" => "4". More interestingly,
2464 : * we can reduce certain boolean expressions even when they contain
2465 : * non-constant subexpressions: "x OR true" => "true" no matter what
2466 : * the subexpression x is. (XXX We assume that no such subexpression
2467 : * will have important side-effects, which is not necessarily a good
2468 : * assumption in the presence of user-defined functions; do we need a
2469 : * pg_proc flag that prevents discarding the execution of a function?)
2470 : *
2471 : * We do understand that certain functions may deliver non-constant
2472 : * results even with constant inputs, "nextval()" being the classic
2473 : * example. Functions that are not marked "immutable" in pg_proc
2474 : * will not be pre-evaluated here, although we will reduce their
2475 : * arguments as far as possible.
2476 : *
2477 : * Whenever a function is eliminated from the expression by means of
2478 : * constant-expression evaluation or inlining, we add the function to
2479 : * root->glob->invalItems. This ensures the plan is known to depend on
2480 : * such functions, even though they aren't referenced anymore.
2481 : *
2482 : * We assume that the tree has already been type-checked and contains
2483 : * only operators and functions that are reasonable to try to execute.
2484 : *
2485 : * NOTE: "root" can be passed as NULL if the caller never wants to do any
2486 : * Param substitutions nor receive info about inlined functions nor reduce
2487 : * NullTest for Vars to constant true or constant false.
2488 : *
2489 : * NOTE: the planner assumes that this will always flatten nested AND and
2490 : * OR clauses into N-argument form. See comments in prepqual.c.
2491 : *
2492 : * NOTE: another critical effect is that any function calls that require
2493 : * default arguments will be expanded, and named-argument calls will be
2494 : * converted to positional notation. The executor won't handle either.
2495 : *--------------------
2496 : */
2497 : Node *
2498 894661 : eval_const_expressions(PlannerInfo *root, Node *node)
2499 : {
2500 : eval_const_expressions_context context;
2501 :
2502 894661 : if (root)
2503 751844 : context.boundParams = root->glob->boundParams; /* bound Params */
2504 : else
2505 142817 : context.boundParams = NULL;
2506 894661 : context.root = root; /* for inlined-function dependencies */
2507 894661 : context.active_fns = NIL; /* nothing being recursively simplified */
2508 894661 : context.case_val = NULL; /* no CASE being examined */
2509 894661 : context.estimate = false; /* safe transformations only */
2510 894661 : return eval_const_expressions_mutator(node, &context);
2511 : }
2512 :
2513 : #define MIN_ARRAY_SIZE_FOR_HASHED_SAOP 9
2514 : /*--------------------
2515 : * convert_saop_to_hashed_saop
2516 : *
2517 : * Recursively search 'node' for ScalarArrayOpExprs and fill in the hash
2518 : * function for any ScalarArrayOpExpr that looks like it would be useful to
2519 : * evaluate using a hash table rather than a linear search.
2520 : *
2521 : * We'll use a hash table if all of the following conditions are met:
2522 : * 1. The 2nd argument of the array contain only Consts.
2523 : * 2. useOr is true or there is a valid negator operator for the
2524 : * ScalarArrayOpExpr's opno.
2525 : * 3. There's valid hash function for both left and righthand operands and
2526 : * these hash functions are the same.
2527 : * 4. If the array contains enough elements for us to consider it to be
2528 : * worthwhile using a hash table rather than a linear search.
2529 : */
2530 : void
2531 653948 : convert_saop_to_hashed_saop(Node *node)
2532 : {
2533 653948 : (void) convert_saop_to_hashed_saop_walker(node, NULL);
2534 653948 : }
2535 :
2536 : static bool
2537 4811084 : convert_saop_to_hashed_saop_walker(Node *node, void *context)
2538 : {
2539 4811084 : if (node == NULL)
2540 111631 : return false;
2541 :
2542 4699453 : if (IsA(node, ScalarArrayOpExpr))
2543 : {
2544 25395 : ScalarArrayOpExpr *saop = (ScalarArrayOpExpr *) node;
2545 25395 : Expr *arrayarg = (Expr *) lsecond(saop->args);
2546 : Oid lefthashfunc;
2547 : Oid righthashfunc;
2548 :
2549 25395 : if (arrayarg && IsA(arrayarg, Const) &&
2550 12906 : !((Const *) arrayarg)->constisnull)
2551 : {
2552 12881 : if (saop->useOr)
2553 : {
2554 11084 : if (get_op_hash_functions(saop->opno, &lefthashfunc, &righthashfunc) &&
2555 10807 : lefthashfunc == righthashfunc)
2556 : {
2557 10786 : Datum arrdatum = ((Const *) arrayarg)->constvalue;
2558 10786 : ArrayType *arr = (ArrayType *) DatumGetPointer(arrdatum);
2559 : int nitems;
2560 :
2561 : /*
2562 : * Only fill in the hash functions if the array looks
2563 : * large enough for it to be worth hashing instead of
2564 : * doing a linear search.
2565 : */
2566 10786 : nitems = ArrayGetNItems(ARR_NDIM(arr), ARR_DIMS(arr));
2567 :
2568 10786 : if (nitems >= MIN_ARRAY_SIZE_FOR_HASHED_SAOP)
2569 : {
2570 : /* Looks good. Fill in the hash functions */
2571 131 : saop->hashfuncid = lefthashfunc;
2572 : }
2573 12442 : return false;
2574 : }
2575 : }
2576 : else /* !saop->useOr */
2577 : {
2578 1797 : Oid negator = get_negator(saop->opno);
2579 :
2580 : /*
2581 : * Check if this is a NOT IN using an operator whose negator
2582 : * is hashable. If so we can still build a hash table and
2583 : * just ensure the lookup items are not in the hash table.
2584 : */
2585 3594 : if (OidIsValid(negator) &&
2586 1797 : get_op_hash_functions(negator, &lefthashfunc, &righthashfunc) &&
2587 1656 : lefthashfunc == righthashfunc)
2588 : {
2589 1656 : Datum arrdatum = ((Const *) arrayarg)->constvalue;
2590 1656 : ArrayType *arr = (ArrayType *) DatumGetPointer(arrdatum);
2591 : int nitems;
2592 :
2593 : /*
2594 : * Only fill in the hash functions if the array looks
2595 : * large enough for it to be worth hashing instead of
2596 : * doing a linear search.
2597 : */
2598 1656 : nitems = ArrayGetNItems(ARR_NDIM(arr), ARR_DIMS(arr));
2599 :
2600 1656 : if (nitems >= MIN_ARRAY_SIZE_FOR_HASHED_SAOP)
2601 : {
2602 : /* Looks good. Fill in the hash functions */
2603 57 : saop->hashfuncid = lefthashfunc;
2604 :
2605 : /*
2606 : * Also set the negfuncid. The executor will need
2607 : * that to perform hashtable lookups.
2608 : */
2609 57 : saop->negfuncid = get_opcode(negator);
2610 : }
2611 1656 : return false;
2612 : }
2613 : }
2614 : }
2615 : }
2616 :
2617 4687011 : return expression_tree_walker(node, convert_saop_to_hashed_saop_walker, NULL);
2618 : }
2619 :
2620 :
2621 : /*--------------------
2622 : * estimate_expression_value
2623 : *
2624 : * This function attempts to estimate the value of an expression for
2625 : * planning purposes. It is in essence a more aggressive version of
2626 : * eval_const_expressions(): we will perform constant reductions that are
2627 : * not necessarily 100% safe, but are reasonable for estimation purposes.
2628 : *
2629 : * Currently the extra steps that are taken in this mode are:
2630 : * 1. Substitute values for Params, where a bound Param value has been made
2631 : * available by the caller of planner(), even if the Param isn't marked
2632 : * constant. This effectively means that we plan using the first supplied
2633 : * value of the Param.
2634 : * 2. Fold stable, as well as immutable, functions to constants.
2635 : * 3. Reduce PlaceHolderVar nodes to their contained expressions.
2636 : *--------------------
2637 : */
2638 : Node *
2639 713104 : estimate_expression_value(PlannerInfo *root, Node *node)
2640 : {
2641 : eval_const_expressions_context context;
2642 :
2643 713104 : context.boundParams = root->glob->boundParams; /* bound Params */
2644 : /* we do not need to mark the plan as depending on inlined functions */
2645 713104 : context.root = NULL;
2646 713104 : context.active_fns = NIL; /* nothing being recursively simplified */
2647 713104 : context.case_val = NULL; /* no CASE being examined */
2648 713104 : context.estimate = true; /* unsafe transformations OK */
2649 713104 : return eval_const_expressions_mutator(node, &context);
2650 : }
2651 :
2652 : /*
2653 : * The generic case in eval_const_expressions_mutator is to recurse using
2654 : * expression_tree_mutator, which will copy the given node unchanged but
2655 : * const-simplify its arguments (if any) as far as possible. If the node
2656 : * itself does immutable processing, and each of its arguments were reduced
2657 : * to a Const, we can then reduce it to a Const using evaluate_expr. (Some
2658 : * node types need more complicated logic; for example, a CASE expression
2659 : * might be reducible to a constant even if not all its subtrees are.)
2660 : */
2661 : #define ece_generic_processing(node) \
2662 : expression_tree_mutator((Node *) (node), eval_const_expressions_mutator, \
2663 : context)
2664 :
2665 : /*
2666 : * Check whether all arguments of the given node were reduced to Consts.
2667 : * By going directly to expression_tree_walker, contain_non_const_walker
2668 : * is not applied to the node itself, only to its children.
2669 : */
2670 : #define ece_all_arguments_const(node) \
2671 : (!expression_tree_walker((Node *) (node), contain_non_const_walker, NULL))
2672 :
2673 : /* Generic macro for applying evaluate_expr */
2674 : #define ece_evaluate_expr(node) \
2675 : ((Node *) evaluate_expr((Expr *) (node), \
2676 : exprType((Node *) (node)), \
2677 : exprTypmod((Node *) (node)), \
2678 : exprCollation((Node *) (node))))
2679 :
2680 : /*
2681 : * Recursive guts of eval_const_expressions/estimate_expression_value
2682 : */
2683 : static Node *
2684 7115569 : eval_const_expressions_mutator(Node *node,
2685 : eval_const_expressions_context *context)
2686 : {
2687 :
2688 : /* since this function recurses, it could be driven to stack overflow */
2689 7115569 : check_stack_depth();
2690 :
2691 7115569 : if (node == NULL)
2692 306895 : return NULL;
2693 6808674 : switch (nodeTag(node))
2694 : {
2695 109723 : case T_Param:
2696 : {
2697 109723 : Param *param = (Param *) node;
2698 109723 : ParamListInfo paramLI = context->boundParams;
2699 :
2700 : /* Look to see if we've been given a value for this Param */
2701 109723 : if (param->paramkind == PARAM_EXTERN &&
2702 32490 : paramLI != NULL &&
2703 32490 : param->paramid > 0 &&
2704 32490 : param->paramid <= paramLI->numParams)
2705 : {
2706 : ParamExternData *prm;
2707 : ParamExternData prmdata;
2708 :
2709 : /*
2710 : * Give hook a chance in case parameter is dynamic. Tell
2711 : * it that this fetch is speculative, so it should avoid
2712 : * erroring out if parameter is unavailable.
2713 : */
2714 32490 : if (paramLI->paramFetch != NULL)
2715 4245 : prm = paramLI->paramFetch(paramLI, param->paramid,
2716 : true, &prmdata);
2717 : else
2718 28245 : prm = ¶mLI->params[param->paramid - 1];
2719 :
2720 : /*
2721 : * We don't just check OidIsValid, but insist that the
2722 : * fetched type match the Param, just in case the hook did
2723 : * something unexpected. No need to throw an error here
2724 : * though; leave that for runtime.
2725 : */
2726 32490 : if (OidIsValid(prm->ptype) &&
2727 32490 : prm->ptype == param->paramtype)
2728 : {
2729 : /* OK to substitute parameter value? */
2730 32490 : if (context->estimate ||
2731 32490 : (prm->pflags & PARAM_FLAG_CONST))
2732 : {
2733 : /*
2734 : * Return a Const representing the param value.
2735 : * Must copy pass-by-ref datatypes, since the
2736 : * Param might be in a memory context
2737 : * shorter-lived than our output plan should be.
2738 : */
2739 : int16 typLen;
2740 : bool typByVal;
2741 : Datum pval;
2742 : Const *con;
2743 :
2744 32490 : get_typlenbyval(param->paramtype,
2745 : &typLen, &typByVal);
2746 32490 : if (prm->isnull || typByVal)
2747 20419 : pval = prm->value;
2748 : else
2749 12071 : pval = datumCopy(prm->value, typByVal, typLen);
2750 32490 : con = makeConst(param->paramtype,
2751 : param->paramtypmod,
2752 : param->paramcollid,
2753 : (int) typLen,
2754 : pval,
2755 32490 : prm->isnull,
2756 : typByVal);
2757 32490 : con->location = param->location;
2758 32490 : return (Node *) con;
2759 : }
2760 : }
2761 : }
2762 :
2763 : /*
2764 : * Not replaceable, so just copy the Param (no need to
2765 : * recurse)
2766 : */
2767 77233 : return (Node *) copyObject(param);
2768 : }
2769 3052 : case T_WindowFunc:
2770 : {
2771 3052 : WindowFunc *expr = (WindowFunc *) node;
2772 3052 : Oid funcid = expr->winfnoid;
2773 : List *args;
2774 : Expr *aggfilter;
2775 : HeapTuple func_tuple;
2776 : WindowFunc *newexpr;
2777 :
2778 : /*
2779 : * We can't really simplify a WindowFunc node, but we mustn't
2780 : * just fall through to the default processing, because we
2781 : * have to apply expand_function_arguments to its argument
2782 : * list. That takes care of inserting default arguments and
2783 : * expanding named-argument notation.
2784 : */
2785 3052 : func_tuple = SearchSysCache1(PROCOID, ObjectIdGetDatum(funcid));
2786 3052 : if (!HeapTupleIsValid(func_tuple))
2787 0 : elog(ERROR, "cache lookup failed for function %u", funcid);
2788 :
2789 3052 : args = expand_function_arguments(expr->args,
2790 : false, expr->wintype,
2791 : func_tuple);
2792 :
2793 3052 : ReleaseSysCache(func_tuple);
2794 :
2795 : /* Now, recursively simplify the args (which are a List) */
2796 : args = (List *)
2797 3052 : expression_tree_mutator((Node *) args,
2798 : eval_const_expressions_mutator,
2799 : context);
2800 : /* ... and the filter expression, which isn't */
2801 : aggfilter = (Expr *)
2802 3052 : eval_const_expressions_mutator((Node *) expr->aggfilter,
2803 : context);
2804 :
2805 : /* And build the replacement WindowFunc node */
2806 3052 : newexpr = makeNode(WindowFunc);
2807 3052 : newexpr->winfnoid = expr->winfnoid;
2808 3052 : newexpr->wintype = expr->wintype;
2809 3052 : newexpr->wincollid = expr->wincollid;
2810 3052 : newexpr->inputcollid = expr->inputcollid;
2811 3052 : newexpr->args = args;
2812 3052 : newexpr->aggfilter = aggfilter;
2813 3052 : newexpr->runCondition = expr->runCondition;
2814 3052 : newexpr->winref = expr->winref;
2815 3052 : newexpr->winstar = expr->winstar;
2816 3052 : newexpr->winagg = expr->winagg;
2817 3052 : newexpr->ignore_nulls = expr->ignore_nulls;
2818 3052 : newexpr->location = expr->location;
2819 :
2820 3052 : return (Node *) newexpr;
2821 : }
2822 379699 : case T_FuncExpr:
2823 : {
2824 379699 : FuncExpr *expr = (FuncExpr *) node;
2825 379699 : List *args = expr->args;
2826 : Expr *simple;
2827 : FuncExpr *newexpr;
2828 :
2829 : /*
2830 : * Code for op/func reduction is pretty bulky, so split it out
2831 : * as a separate function. Note: exprTypmod normally returns
2832 : * -1 for a FuncExpr, but not when the node is recognizably a
2833 : * length coercion; we want to preserve the typmod in the
2834 : * eventual Const if so.
2835 : */
2836 379699 : simple = simplify_function(expr->funcid,
2837 : expr->funcresulttype,
2838 : exprTypmod(node),
2839 : expr->funccollid,
2840 : expr->inputcollid,
2841 : &args,
2842 379699 : expr->funcvariadic,
2843 : true,
2844 : true,
2845 : context);
2846 377843 : if (simple) /* successfully simplified it */
2847 110661 : return (Node *) simple;
2848 :
2849 : /*
2850 : * The expression cannot be simplified any further, so build
2851 : * and return a replacement FuncExpr node using the
2852 : * possibly-simplified arguments. Note that we have also
2853 : * converted the argument list to positional notation.
2854 : */
2855 267182 : newexpr = makeNode(FuncExpr);
2856 267182 : newexpr->funcid = expr->funcid;
2857 267182 : newexpr->funcresulttype = expr->funcresulttype;
2858 267182 : newexpr->funcretset = expr->funcretset;
2859 267182 : newexpr->funcvariadic = expr->funcvariadic;
2860 267182 : newexpr->funcformat = expr->funcformat;
2861 267182 : newexpr->funccollid = expr->funccollid;
2862 267182 : newexpr->inputcollid = expr->inputcollid;
2863 267182 : newexpr->args = args;
2864 267182 : newexpr->location = expr->location;
2865 267182 : return (Node *) newexpr;
2866 : }
2867 37908 : case T_Aggref:
2868 37908 : node = ece_generic_processing(node);
2869 37908 : if (context->root != NULL)
2870 37908 : return simplify_aggref((Aggref *) node, context);
2871 0 : return node;
2872 554222 : case T_OpExpr:
2873 : {
2874 554222 : OpExpr *expr = (OpExpr *) node;
2875 554222 : List *args = expr->args;
2876 : Expr *simple;
2877 : OpExpr *newexpr;
2878 :
2879 : /*
2880 : * Need to get OID of underlying function. Okay to scribble
2881 : * on input to this extent.
2882 : */
2883 554222 : set_opfuncid(expr);
2884 :
2885 : /*
2886 : * Code for op/func reduction is pretty bulky, so split it out
2887 : * as a separate function.
2888 : */
2889 554222 : simple = simplify_function(expr->opfuncid,
2890 : expr->opresulttype, -1,
2891 : expr->opcollid,
2892 : expr->inputcollid,
2893 : &args,
2894 : false,
2895 : true,
2896 : true,
2897 : context);
2898 553444 : if (simple) /* successfully simplified it */
2899 20125 : return (Node *) simple;
2900 :
2901 : /*
2902 : * If the operator is boolean equality or inequality, we know
2903 : * how to simplify cases involving one constant and one
2904 : * non-constant argument.
2905 : */
2906 533319 : if (expr->opno == BooleanEqualOperator ||
2907 531706 : expr->opno == BooleanNotEqualOperator)
2908 : {
2909 1753 : simple = (Expr *) simplify_boolean_equality(expr->opno,
2910 : args);
2911 1753 : if (simple) /* successfully simplified it */
2912 1268 : return (Node *) simple;
2913 : }
2914 :
2915 : /*
2916 : * The expression cannot be simplified any further, so build
2917 : * and return a replacement OpExpr node using the
2918 : * possibly-simplified arguments.
2919 : */
2920 532051 : newexpr = makeNode(OpExpr);
2921 532051 : newexpr->opno = expr->opno;
2922 532051 : newexpr->opfuncid = expr->opfuncid;
2923 532051 : newexpr->opresulttype = expr->opresulttype;
2924 532051 : newexpr->opretset = expr->opretset;
2925 532051 : newexpr->opcollid = expr->opcollid;
2926 532051 : newexpr->inputcollid = expr->inputcollid;
2927 532051 : newexpr->args = args;
2928 532051 : newexpr->location = expr->location;
2929 532051 : return (Node *) newexpr;
2930 : }
2931 960 : case T_DistinctExpr:
2932 : {
2933 960 : DistinctExpr *expr = (DistinctExpr *) node;
2934 : List *args;
2935 : ListCell *arg;
2936 960 : bool has_null_input = false;
2937 960 : bool all_null_input = true;
2938 960 : bool has_nonconst_input = false;
2939 960 : bool has_nullable_nonconst = false;
2940 : Expr *simple;
2941 : DistinctExpr *newexpr;
2942 :
2943 : /*
2944 : * Reduce constants in the DistinctExpr's arguments. We know
2945 : * args is either NIL or a List node, so we can call
2946 : * expression_tree_mutator directly rather than recursing to
2947 : * self.
2948 : */
2949 960 : args = (List *) expression_tree_mutator((Node *) expr->args,
2950 : eval_const_expressions_mutator,
2951 : context);
2952 :
2953 : /*
2954 : * We must do our own check for NULLs because DistinctExpr has
2955 : * different results for NULL input than the underlying
2956 : * operator does. We also check if any non-constant input is
2957 : * potentially nullable.
2958 : */
2959 2880 : foreach(arg, args)
2960 : {
2961 1920 : if (IsA(lfirst(arg), Const))
2962 : {
2963 335 : has_null_input |= ((Const *) lfirst(arg))->constisnull;
2964 335 : all_null_input &= ((Const *) lfirst(arg))->constisnull;
2965 : }
2966 : else
2967 : {
2968 1585 : has_nonconst_input = true;
2969 1585 : all_null_input = false;
2970 :
2971 1585 : if (!has_nullable_nonconst &&
2972 940 : !expr_is_nonnullable(context->root,
2973 940 : (Expr *) lfirst(arg),
2974 : NOTNULL_SOURCE_HASHTABLE))
2975 855 : has_nullable_nonconst = true;
2976 : }
2977 : }
2978 :
2979 960 : if (!has_nonconst_input)
2980 : {
2981 : /*
2982 : * All inputs are constants. We can optimize this out
2983 : * completely.
2984 : */
2985 :
2986 : /* all nulls? then not distinct */
2987 45 : if (all_null_input)
2988 10 : return makeBoolConst(false, false);
2989 :
2990 : /* one null? then distinct */
2991 35 : if (has_null_input)
2992 15 : return makeBoolConst(true, false);
2993 :
2994 : /* otherwise try to evaluate the '=' operator */
2995 : /* (NOT okay to try to inline it, though!) */
2996 :
2997 : /*
2998 : * Need to get OID of underlying function. Okay to
2999 : * scribble on input to this extent.
3000 : */
3001 20 : set_opfuncid((OpExpr *) expr); /* rely on struct
3002 : * equivalence */
3003 :
3004 : /*
3005 : * Code for op/func reduction is pretty bulky, so split it
3006 : * out as a separate function.
3007 : */
3008 20 : simple = simplify_function(expr->opfuncid,
3009 : expr->opresulttype, -1,
3010 : expr->opcollid,
3011 : expr->inputcollid,
3012 : &args,
3013 : false,
3014 : false,
3015 : false,
3016 : context);
3017 20 : if (simple) /* successfully simplified it */
3018 : {
3019 : /*
3020 : * Since the underlying operator is "=", must negate
3021 : * its result
3022 : */
3023 20 : Const *csimple = castNode(Const, simple);
3024 :
3025 20 : csimple->constvalue =
3026 20 : BoolGetDatum(!DatumGetBool(csimple->constvalue));
3027 20 : return (Node *) csimple;
3028 : }
3029 : }
3030 915 : else if (!has_nullable_nonconst)
3031 : {
3032 : /*
3033 : * There are non-constant inputs, but since all of them
3034 : * are proven non-nullable, "IS DISTINCT FROM" semantics
3035 : * are much simpler.
3036 : */
3037 :
3038 : OpExpr *eqexpr;
3039 :
3040 : /*
3041 : * If one input is an explicit NULL constant, and the
3042 : * other is a non-nullable expression, the result is
3043 : * always TRUE.
3044 : */
3045 60 : if (has_null_input)
3046 20 : return makeBoolConst(true, false);
3047 :
3048 : /*
3049 : * Otherwise, both inputs are known non-nullable. In this
3050 : * case, "IS DISTINCT FROM" is equivalent to the standard
3051 : * inequality operator (usually "<>"). We convert this to
3052 : * an OpExpr, which is a more efficient representation for
3053 : * the planner. It can enable the use of partial indexes
3054 : * and constraint exclusion. Furthermore, if the clause
3055 : * is negated (ie, "IS NOT DISTINCT FROM"), the resulting
3056 : * "=" operator can allow the planner to use index scans,
3057 : * merge joins, hash joins, and EC-based qual deductions.
3058 : */
3059 40 : eqexpr = makeNode(OpExpr);
3060 40 : eqexpr->opno = expr->opno;
3061 40 : eqexpr->opfuncid = expr->opfuncid;
3062 40 : eqexpr->opresulttype = BOOLOID;
3063 40 : eqexpr->opretset = expr->opretset;
3064 40 : eqexpr->opcollid = expr->opcollid;
3065 40 : eqexpr->inputcollid = expr->inputcollid;
3066 40 : eqexpr->args = args;
3067 40 : eqexpr->location = expr->location;
3068 :
3069 40 : return eval_const_expressions_mutator(negate_clause((Node *) eqexpr),
3070 : context);
3071 : }
3072 855 : else if (has_null_input)
3073 : {
3074 : /*
3075 : * One input is a nullable non-constant expression, and
3076 : * the other is an explicit NULL constant. We can
3077 : * transform this to a NullTest with !argisrow, which is
3078 : * much more amenable to optimization.
3079 : */
3080 :
3081 40 : NullTest *nt = makeNode(NullTest);
3082 :
3083 80 : nt->arg = (Expr *) (IsA(linitial(args), Const) ?
3084 40 : lsecond(args) : linitial(args));
3085 40 : nt->nulltesttype = IS_NOT_NULL;
3086 :
3087 : /*
3088 : * argisrow = false is correct whether or not arg is
3089 : * composite
3090 : */
3091 40 : nt->argisrow = false;
3092 40 : nt->location = expr->location;
3093 :
3094 40 : return eval_const_expressions_mutator((Node *) nt, context);
3095 : }
3096 :
3097 : /*
3098 : * The expression cannot be simplified any further, so build
3099 : * and return a replacement DistinctExpr node using the
3100 : * possibly-simplified arguments.
3101 : */
3102 815 : newexpr = makeNode(DistinctExpr);
3103 815 : newexpr->opno = expr->opno;
3104 815 : newexpr->opfuncid = expr->opfuncid;
3105 815 : newexpr->opresulttype = expr->opresulttype;
3106 815 : newexpr->opretset = expr->opretset;
3107 815 : newexpr->opcollid = expr->opcollid;
3108 815 : newexpr->inputcollid = expr->inputcollid;
3109 815 : newexpr->args = args;
3110 815 : newexpr->location = expr->location;
3111 815 : return (Node *) newexpr;
3112 : }
3113 904 : case T_NullIfExpr:
3114 : {
3115 : NullIfExpr *expr;
3116 : ListCell *arg;
3117 904 : bool has_nonconst_input = false;
3118 :
3119 : /* Copy the node and const-simplify its arguments */
3120 904 : expr = (NullIfExpr *) ece_generic_processing(node);
3121 :
3122 : /* If either argument is NULL they can't be equal */
3123 2707 : foreach(arg, expr->args)
3124 : {
3125 1808 : if (!IsA(lfirst(arg), Const))
3126 878 : has_nonconst_input = true;
3127 930 : else if (((Const *) lfirst(arg))->constisnull)
3128 5 : return (Node *) linitial(expr->args);
3129 : }
3130 :
3131 : /*
3132 : * Need to get OID of underlying function before checking if
3133 : * the function is OK to evaluate.
3134 : */
3135 899 : set_opfuncid((OpExpr *) expr);
3136 :
3137 930 : if (!has_nonconst_input &&
3138 31 : ece_function_is_safe(expr->opfuncid, context))
3139 31 : return ece_evaluate_expr(expr);
3140 :
3141 868 : return (Node *) expr;
3142 : }
3143 29139 : case T_ScalarArrayOpExpr:
3144 : {
3145 : ScalarArrayOpExpr *saop;
3146 :
3147 : /* Copy the node and const-simplify its arguments */
3148 29139 : saop = (ScalarArrayOpExpr *) ece_generic_processing(node);
3149 :
3150 : /* Make sure we know underlying function */
3151 29139 : set_sa_opfuncid(saop);
3152 :
3153 : /*
3154 : * If all arguments are Consts, and it's a safe function, we
3155 : * can fold to a constant
3156 : */
3157 29408 : if (ece_all_arguments_const(saop) &&
3158 269 : ece_function_is_safe(saop->opfuncid, context))
3159 269 : return ece_evaluate_expr(saop);
3160 28870 : return (Node *) saop;
3161 : }
3162 146617 : case T_BoolExpr:
3163 : {
3164 146617 : BoolExpr *expr = (BoolExpr *) node;
3165 :
3166 146617 : switch (expr->boolop)
3167 : {
3168 15299 : case OR_EXPR:
3169 : {
3170 : List *newargs;
3171 15299 : bool haveNull = false;
3172 15299 : bool forceTrue = false;
3173 :
3174 15299 : newargs = simplify_or_arguments(expr->args,
3175 : context,
3176 : &haveNull,
3177 : &forceTrue);
3178 15299 : if (forceTrue)
3179 106 : return makeBoolConst(true, false);
3180 15193 : if (haveNull)
3181 3802 : newargs = lappend(newargs,
3182 3802 : makeBoolConst(false, true));
3183 : /* If all the inputs are FALSE, result is FALSE */
3184 15193 : if (newargs == NIL)
3185 23 : return makeBoolConst(false, false);
3186 :
3187 : /*
3188 : * If only one nonconst-or-NULL input, it's the
3189 : * result
3190 : */
3191 15170 : if (list_length(newargs) == 1)
3192 87 : return (Node *) linitial(newargs);
3193 : /* Else we still need an OR node */
3194 15083 : return (Node *) make_orclause(newargs);
3195 : }
3196 116372 : case AND_EXPR:
3197 : {
3198 : List *newargs;
3199 116372 : bool haveNull = false;
3200 116372 : bool forceFalse = false;
3201 :
3202 116372 : newargs = simplify_and_arguments(expr->args,
3203 : context,
3204 : &haveNull,
3205 : &forceFalse);
3206 116372 : if (forceFalse)
3207 645 : return makeBoolConst(false, false);
3208 115727 : if (haveNull)
3209 25 : newargs = lappend(newargs,
3210 25 : makeBoolConst(false, true));
3211 : /* If all the inputs are TRUE, result is TRUE */
3212 115727 : if (newargs == NIL)
3213 186 : return makeBoolConst(true, false);
3214 :
3215 : /*
3216 : * If only one nonconst-or-NULL input, it's the
3217 : * result
3218 : */
3219 115541 : if (list_length(newargs) == 1)
3220 177 : return (Node *) linitial(newargs);
3221 : /* Else we still need an AND node */
3222 115364 : return (Node *) make_andclause(newargs);
3223 : }
3224 14946 : case NOT_EXPR:
3225 : {
3226 : Node *arg;
3227 :
3228 : Assert(list_length(expr->args) == 1);
3229 14946 : arg = eval_const_expressions_mutator(linitial(expr->args),
3230 : context);
3231 :
3232 : /*
3233 : * Use negate_clause() to see if we can simplify
3234 : * away the NOT.
3235 : */
3236 14946 : return negate_clause(arg);
3237 : }
3238 0 : default:
3239 0 : elog(ERROR, "unrecognized boolop: %d",
3240 : (int) expr->boolop);
3241 : break;
3242 : }
3243 : break;
3244 : }
3245 :
3246 637 : case T_JsonValueExpr:
3247 : {
3248 637 : JsonValueExpr *jve = (JsonValueExpr *) node;
3249 637 : Node *raw_expr = (Node *) jve->raw_expr;
3250 637 : Node *formatted_expr = (Node *) jve->formatted_expr;
3251 :
3252 : /*
3253 : * If we can fold formatted_expr to a constant, we can elide
3254 : * the JsonValueExpr altogether. Otherwise we must process
3255 : * raw_expr too. But JsonFormat is a flat node and requires
3256 : * no simplification, only copying.
3257 : */
3258 637 : formatted_expr = eval_const_expressions_mutator(formatted_expr,
3259 : context);
3260 637 : if (formatted_expr && IsA(formatted_expr, Const))
3261 443 : return formatted_expr;
3262 :
3263 194 : raw_expr = eval_const_expressions_mutator(raw_expr, context);
3264 :
3265 194 : return (Node *) makeJsonValueExpr((Expr *) raw_expr,
3266 : (Expr *) formatted_expr,
3267 194 : copyObject(jve->format));
3268 : }
3269 :
3270 485 : case T_SubPlan:
3271 : case T_AlternativeSubPlan:
3272 :
3273 : /*
3274 : * Return a SubPlan unchanged --- too late to do anything with it.
3275 : *
3276 : * XXX should we ereport() here instead? Probably this routine
3277 : * should never be invoked after SubPlan creation.
3278 : */
3279 485 : return node;
3280 129232 : case T_RelabelType:
3281 : {
3282 129232 : RelabelType *relabel = (RelabelType *) node;
3283 : Node *arg;
3284 :
3285 : /* Simplify the input ... */
3286 129232 : arg = eval_const_expressions_mutator((Node *) relabel->arg,
3287 : context);
3288 : /* ... and attach a new RelabelType node, if needed */
3289 129228 : return applyRelabelType(arg,
3290 : relabel->resulttype,
3291 : relabel->resulttypmod,
3292 : relabel->resultcollid,
3293 : relabel->relabelformat,
3294 : relabel->location,
3295 : true);
3296 : }
3297 24747 : case T_CoerceViaIO:
3298 : {
3299 24747 : CoerceViaIO *expr = (CoerceViaIO *) node;
3300 : List *args;
3301 : Oid outfunc;
3302 : bool outtypisvarlena;
3303 : Oid infunc;
3304 : Oid intypioparam;
3305 : Expr *simple;
3306 : CoerceViaIO *newexpr;
3307 :
3308 : /* Make a List so we can use simplify_function */
3309 24747 : args = list_make1(expr->arg);
3310 :
3311 : /*
3312 : * CoerceViaIO represents calling the source type's output
3313 : * function then the result type's input function. So, try to
3314 : * simplify it as though it were a stack of two such function
3315 : * calls. First we need to know what the functions are.
3316 : *
3317 : * Note that the coercion functions are assumed not to care
3318 : * about input collation, so we just pass InvalidOid for that.
3319 : */
3320 24747 : getTypeOutputInfo(exprType((Node *) expr->arg),
3321 : &outfunc, &outtypisvarlena);
3322 24747 : getTypeInputInfo(expr->resulttype,
3323 : &infunc, &intypioparam);
3324 :
3325 24747 : simple = simplify_function(outfunc,
3326 : CSTRINGOID, -1,
3327 : InvalidOid,
3328 : InvalidOid,
3329 : &args,
3330 : false,
3331 : true,
3332 : true,
3333 : context);
3334 24747 : if (simple) /* successfully simplified output fn */
3335 : {
3336 : /*
3337 : * Input functions may want 1 to 3 arguments. We always
3338 : * supply all three, trusting that nothing downstream will
3339 : * complain.
3340 : */
3341 1813 : args = list_make3(simple,
3342 : makeConst(OIDOID,
3343 : -1,
3344 : InvalidOid,
3345 : sizeof(Oid),
3346 : ObjectIdGetDatum(intypioparam),
3347 : false,
3348 : true),
3349 : makeConst(INT4OID,
3350 : -1,
3351 : InvalidOid,
3352 : sizeof(int32),
3353 : Int32GetDatum(-1),
3354 : false,
3355 : true));
3356 :
3357 1813 : simple = simplify_function(infunc,
3358 : expr->resulttype, -1,
3359 : expr->resultcollid,
3360 : InvalidOid,
3361 : &args,
3362 : false,
3363 : false,
3364 : true,
3365 : context);
3366 1740 : if (simple) /* successfully simplified input fn */
3367 1686 : return (Node *) simple;
3368 : }
3369 :
3370 : /*
3371 : * The expression cannot be simplified any further, so build
3372 : * and return a replacement CoerceViaIO node using the
3373 : * possibly-simplified argument.
3374 : */
3375 22988 : newexpr = makeNode(CoerceViaIO);
3376 22988 : newexpr->arg = (Expr *) linitial(args);
3377 22988 : newexpr->resulttype = expr->resulttype;
3378 22988 : newexpr->resultcollid = expr->resultcollid;
3379 22988 : newexpr->coerceformat = expr->coerceformat;
3380 22988 : newexpr->location = expr->location;
3381 22988 : return (Node *) newexpr;
3382 : }
3383 8151 : case T_ArrayCoerceExpr:
3384 : {
3385 8151 : ArrayCoerceExpr *ac = makeNode(ArrayCoerceExpr);
3386 : Node *save_case_val;
3387 :
3388 : /*
3389 : * Copy the node and const-simplify its arguments. We can't
3390 : * use ece_generic_processing() here because we need to mess
3391 : * with case_val only while processing the elemexpr.
3392 : */
3393 8151 : memcpy(ac, node, sizeof(ArrayCoerceExpr));
3394 8151 : ac->arg = (Expr *)
3395 8151 : eval_const_expressions_mutator((Node *) ac->arg,
3396 : context);
3397 :
3398 : /*
3399 : * Set up for the CaseTestExpr node contained in the elemexpr.
3400 : * We must prevent it from absorbing any outer CASE value.
3401 : */
3402 8151 : save_case_val = context->case_val;
3403 8151 : context->case_val = NULL;
3404 :
3405 8151 : ac->elemexpr = (Expr *)
3406 8151 : eval_const_expressions_mutator((Node *) ac->elemexpr,
3407 : context);
3408 :
3409 8151 : context->case_val = save_case_val;
3410 :
3411 : /*
3412 : * If constant argument and the per-element expression is
3413 : * immutable, we can simplify the whole thing to a constant.
3414 : * Exception: although contain_mutable_functions considers
3415 : * CoerceToDomain immutable for historical reasons, let's not
3416 : * do so here; this ensures coercion to an array-over-domain
3417 : * does not apply the domain's constraints until runtime.
3418 : */
3419 8151 : if (ac->arg && IsA(ac->arg, Const) &&
3420 884 : ac->elemexpr && !IsA(ac->elemexpr, CoerceToDomain) &&
3421 864 : !contain_mutable_functions((Node *) ac->elemexpr))
3422 864 : return ece_evaluate_expr(ac);
3423 :
3424 7287 : return (Node *) ac;
3425 : }
3426 8095 : case T_CollateExpr:
3427 : {
3428 : /*
3429 : * We replace CollateExpr with RelabelType, so as to improve
3430 : * uniformity of expression representation and thus simplify
3431 : * comparison of expressions. Hence this looks very nearly
3432 : * the same as the RelabelType case, and we can apply the same
3433 : * optimizations to avoid unnecessary RelabelTypes.
3434 : */
3435 8095 : CollateExpr *collate = (CollateExpr *) node;
3436 : Node *arg;
3437 :
3438 : /* Simplify the input ... */
3439 8095 : arg = eval_const_expressions_mutator((Node *) collate->arg,
3440 : context);
3441 : /* ... and attach a new RelabelType node, if needed */
3442 8095 : return applyRelabelType(arg,
3443 : exprType(arg),
3444 : exprTypmod(arg),
3445 : collate->collOid,
3446 : COERCE_IMPLICIT_CAST,
3447 : collate->location,
3448 : true);
3449 : }
3450 28014 : case T_CaseExpr:
3451 : {
3452 : /*----------
3453 : * CASE expressions can be simplified if there are constant
3454 : * condition clauses:
3455 : * FALSE (or NULL): drop the alternative
3456 : * TRUE: drop all remaining alternatives
3457 : * If the first non-FALSE alternative is a constant TRUE,
3458 : * we can simplify the entire CASE to that alternative's
3459 : * expression. If there are no non-FALSE alternatives,
3460 : * we simplify the entire CASE to the default result (ELSE).
3461 : *
3462 : * If we have a simple-form CASE with constant test
3463 : * expression, we substitute the constant value for contained
3464 : * CaseTestExpr placeholder nodes, so that we have the
3465 : * opportunity to reduce constant test conditions. For
3466 : * example this allows
3467 : * CASE 0 WHEN 0 THEN 1 ELSE 1/0 END
3468 : * to reduce to 1 rather than drawing a divide-by-0 error.
3469 : * Note that when the test expression is constant, we don't
3470 : * have to include it in the resulting CASE; for example
3471 : * CASE 0 WHEN x THEN y ELSE z END
3472 : * is transformed by the parser to
3473 : * CASE 0 WHEN CaseTestExpr = x THEN y ELSE z END
3474 : * which we can simplify to
3475 : * CASE WHEN 0 = x THEN y ELSE z END
3476 : * It is not necessary for the executor to evaluate the "arg"
3477 : * expression when executing the CASE, since any contained
3478 : * CaseTestExprs that might have referred to it will have been
3479 : * replaced by the constant.
3480 : *----------
3481 : */
3482 28014 : CaseExpr *caseexpr = (CaseExpr *) node;
3483 : CaseExpr *newcase;
3484 : Node *save_case_val;
3485 : Node *newarg;
3486 : List *newargs;
3487 : bool const_true_cond;
3488 28014 : Node *defresult = NULL;
3489 : ListCell *arg;
3490 :
3491 : /* Simplify the test expression, if any */
3492 28014 : newarg = eval_const_expressions_mutator((Node *) caseexpr->arg,
3493 : context);
3494 :
3495 : /* Set up for contained CaseTestExpr nodes */
3496 28014 : save_case_val = context->case_val;
3497 28014 : if (newarg && IsA(newarg, Const))
3498 : {
3499 65 : context->case_val = newarg;
3500 65 : newarg = NULL; /* not needed anymore, see above */
3501 : }
3502 : else
3503 27949 : context->case_val = NULL;
3504 :
3505 : /* Simplify the WHEN clauses */
3506 28014 : newargs = NIL;
3507 28014 : const_true_cond = false;
3508 85598 : foreach(arg, caseexpr->args)
3509 : {
3510 57995 : CaseWhen *oldcasewhen = lfirst_node(CaseWhen, arg);
3511 : Node *casecond;
3512 : Node *caseresult;
3513 :
3514 : /* Simplify this alternative's test condition */
3515 57995 : casecond = eval_const_expressions_mutator((Node *) oldcasewhen->expr,
3516 : context);
3517 :
3518 : /*
3519 : * If the test condition is constant FALSE (or NULL), then
3520 : * drop this WHEN clause completely, without processing
3521 : * the result.
3522 : */
3523 57995 : if (casecond && IsA(casecond, Const))
3524 : {
3525 852 : Const *const_input = (Const *) casecond;
3526 :
3527 852 : if (const_input->constisnull ||
3528 852 : !DatumGetBool(const_input->constvalue))
3529 445 : continue; /* drop alternative with FALSE cond */
3530 : /* Else it's constant TRUE */
3531 407 : const_true_cond = true;
3532 : }
3533 :
3534 : /* Simplify this alternative's result value */
3535 57550 : caseresult = eval_const_expressions_mutator((Node *) oldcasewhen->result,
3536 : context);
3537 :
3538 : /* If non-constant test condition, emit a new WHEN node */
3539 57546 : if (!const_true_cond)
3540 57139 : {
3541 57139 : CaseWhen *newcasewhen = makeNode(CaseWhen);
3542 :
3543 57139 : newcasewhen->expr = (Expr *) casecond;
3544 57139 : newcasewhen->result = (Expr *) caseresult;
3545 57139 : newcasewhen->location = oldcasewhen->location;
3546 57139 : newargs = lappend(newargs, newcasewhen);
3547 57139 : continue;
3548 : }
3549 :
3550 : /*
3551 : * Found a TRUE condition, so none of the remaining
3552 : * alternatives can be reached. We treat the result as
3553 : * the default result.
3554 : */
3555 407 : defresult = caseresult;
3556 407 : break;
3557 : }
3558 :
3559 : /* Simplify the default result, unless we replaced it above */
3560 28010 : if (!const_true_cond)
3561 27603 : defresult = eval_const_expressions_mutator((Node *) caseexpr->defresult,
3562 : context);
3563 :
3564 28010 : context->case_val = save_case_val;
3565 :
3566 : /*
3567 : * If no non-FALSE alternatives, CASE reduces to the default
3568 : * result
3569 : */
3570 28010 : if (newargs == NIL)
3571 623 : return defresult;
3572 : /* Otherwise we need a new CASE node */
3573 27387 : newcase = makeNode(CaseExpr);
3574 27387 : newcase->casetype = caseexpr->casetype;
3575 27387 : newcase->casecollid = caseexpr->casecollid;
3576 27387 : newcase->arg = (Expr *) newarg;
3577 27387 : newcase->args = newargs;
3578 27387 : newcase->defresult = (Expr *) defresult;
3579 27387 : newcase->location = caseexpr->location;
3580 27387 : return (Node *) newcase;
3581 : }
3582 28148 : case T_CaseTestExpr:
3583 : {
3584 : /*
3585 : * If we know a constant test value for the current CASE
3586 : * construct, substitute it for the placeholder. Else just
3587 : * return the placeholder as-is.
3588 : */
3589 28148 : if (context->case_val)
3590 116 : return copyObject(context->case_val);
3591 : else
3592 28032 : return copyObject(node);
3593 : }
3594 48225 : case T_SubscriptingRef:
3595 : case T_ArrayExpr:
3596 : case T_RowExpr:
3597 : case T_MinMaxExpr:
3598 : {
3599 : /*
3600 : * Generic handling for node types whose own processing is
3601 : * known to be immutable, and for which we need no smarts
3602 : * beyond "simplify if all inputs are constants".
3603 : *
3604 : * Treating SubscriptingRef this way assumes that subscripting
3605 : * fetch and assignment are both immutable. This constrains
3606 : * type-specific subscripting implementations; maybe we should
3607 : * relax it someday.
3608 : *
3609 : * Treating MinMaxExpr this way amounts to assuming that the
3610 : * btree comparison function it calls is immutable; see the
3611 : * reasoning in contain_mutable_functions_walker.
3612 : */
3613 :
3614 : /* Copy the node and const-simplify its arguments */
3615 48225 : node = ece_generic_processing(node);
3616 : /* If all arguments are Consts, we can fold to a constant */
3617 48225 : if (ece_all_arguments_const(node))
3618 23194 : return ece_evaluate_expr(node);
3619 25031 : return node;
3620 : }
3621 2384 : case T_CoalesceExpr:
3622 : {
3623 2384 : CoalesceExpr *coalesceexpr = (CoalesceExpr *) node;
3624 : CoalesceExpr *newcoalesce;
3625 : List *newargs;
3626 : ListCell *arg;
3627 :
3628 2384 : newargs = NIL;
3629 5712 : foreach(arg, coalesceexpr->args)
3630 : {
3631 : Node *e;
3632 :
3633 4676 : e = eval_const_expressions_mutator((Node *) lfirst(arg),
3634 : context);
3635 :
3636 : /*
3637 : * We can remove null constants from the list. For a
3638 : * nonnullable expression, if it has not been preceded by
3639 : * any non-null-constant expressions then it is the
3640 : * result. Otherwise, it's the next argument, but we can
3641 : * drop following arguments since they will never be
3642 : * reached.
3643 : */
3644 4676 : if (IsA(e, Const))
3645 : {
3646 1314 : if (((Const *) e)->constisnull)
3647 46 : continue; /* drop null constant */
3648 1268 : if (newargs == NIL)
3649 133 : return e; /* first expr */
3650 1185 : newargs = lappend(newargs, e);
3651 1185 : break;
3652 : }
3653 3362 : if (expr_is_nonnullable(context->root, (Expr *) e,
3654 : NOTNULL_SOURCE_HASHTABLE))
3655 : {
3656 80 : if (newargs == NIL)
3657 50 : return e; /* first expr */
3658 30 : newargs = lappend(newargs, e);
3659 30 : break;
3660 : }
3661 :
3662 3282 : newargs = lappend(newargs, e);
3663 : }
3664 :
3665 : /*
3666 : * If all the arguments were constant null, the result is just
3667 : * null
3668 : */
3669 2251 : if (newargs == NIL)
3670 0 : return (Node *) makeNullConst(coalesceexpr->coalescetype,
3671 : -1,
3672 : coalesceexpr->coalescecollid);
3673 :
3674 : /*
3675 : * If there's exactly one surviving argument, we no longer
3676 : * need COALESCE at all: the result is that argument
3677 : */
3678 2251 : if (list_length(newargs) == 1)
3679 15 : return (Node *) linitial(newargs);
3680 :
3681 2236 : newcoalesce = makeNode(CoalesceExpr);
3682 2236 : newcoalesce->coalescetype = coalesceexpr->coalescetype;
3683 2236 : newcoalesce->coalescecollid = coalesceexpr->coalescecollid;
3684 2236 : newcoalesce->args = newargs;
3685 2236 : newcoalesce->location = coalesceexpr->location;
3686 2236 : return (Node *) newcoalesce;
3687 : }
3688 4106 : case T_SQLValueFunction:
3689 : {
3690 : /*
3691 : * All variants of SQLValueFunction are stable, so if we are
3692 : * estimating the expression's value, we should evaluate the
3693 : * current function value. Otherwise just copy.
3694 : */
3695 4106 : SQLValueFunction *svf = (SQLValueFunction *) node;
3696 :
3697 4106 : if (context->estimate)
3698 742 : return (Node *) evaluate_expr((Expr *) svf,
3699 : svf->type,
3700 : svf->typmod,
3701 : InvalidOid);
3702 : else
3703 3364 : return copyObject((Node *) svf);
3704 : }
3705 24964 : case T_FieldSelect:
3706 : {
3707 : /*
3708 : * We can optimize field selection from a whole-row Var into a
3709 : * simple Var. (This case won't be generated directly by the
3710 : * parser, because ParseComplexProjection short-circuits it.
3711 : * But it can arise while simplifying functions.) Also, we
3712 : * can optimize field selection from a RowExpr construct, or
3713 : * of course from a constant.
3714 : *
3715 : * However, replacing a whole-row Var in this way has a
3716 : * pitfall: if we've already built the rel targetlist for the
3717 : * source relation, then the whole-row Var is scheduled to be
3718 : * produced by the relation scan, but the simple Var probably
3719 : * isn't, which will lead to a failure in setrefs.c. This is
3720 : * not a problem when handling simple single-level queries, in
3721 : * which expression simplification always happens first. It
3722 : * is a risk for lateral references from subqueries, though.
3723 : * To avoid such failures, don't optimize uplevel references.
3724 : *
3725 : * We must also check that the declared type of the field is
3726 : * still the same as when the FieldSelect was created --- this
3727 : * can change if someone did ALTER COLUMN TYPE on the rowtype.
3728 : * If it isn't, we skip the optimization; the case will
3729 : * probably fail at runtime, but that's not our problem here.
3730 : */
3731 24964 : FieldSelect *fselect = (FieldSelect *) node;
3732 : FieldSelect *newfselect;
3733 : Node *arg;
3734 :
3735 24964 : arg = eval_const_expressions_mutator((Node *) fselect->arg,
3736 : context);
3737 24964 : if (arg && IsA(arg, Var) &&
3738 21924 : ((Var *) arg)->varattno == InvalidAttrNumber &&
3739 75 : ((Var *) arg)->varlevelsup == 0)
3740 : {
3741 65 : if (rowtype_field_matches(((Var *) arg)->vartype,
3742 65 : fselect->fieldnum,
3743 : fselect->resulttype,
3744 : fselect->resulttypmod,
3745 : fselect->resultcollid))
3746 : {
3747 : Var *newvar;
3748 :
3749 65 : newvar = makeVar(((Var *) arg)->varno,
3750 65 : fselect->fieldnum,
3751 : fselect->resulttype,
3752 : fselect->resulttypmod,
3753 : fselect->resultcollid,
3754 : ((Var *) arg)->varlevelsup);
3755 : /* New Var has same OLD/NEW returning as old one */
3756 65 : newvar->varreturningtype = ((Var *) arg)->varreturningtype;
3757 : /* New Var is nullable by same rels as the old one */
3758 65 : newvar->varnullingrels = ((Var *) arg)->varnullingrels;
3759 65 : return (Node *) newvar;
3760 : }
3761 : }
3762 24899 : if (arg && IsA(arg, RowExpr))
3763 : {
3764 20 : RowExpr *rowexpr = (RowExpr *) arg;
3765 :
3766 40 : if (fselect->fieldnum > 0 &&
3767 20 : fselect->fieldnum <= list_length(rowexpr->args))
3768 : {
3769 20 : Node *fld = (Node *) list_nth(rowexpr->args,
3770 20 : fselect->fieldnum - 1);
3771 :
3772 20 : if (rowtype_field_matches(rowexpr->row_typeid,
3773 20 : fselect->fieldnum,
3774 : fselect->resulttype,
3775 : fselect->resulttypmod,
3776 20 : fselect->resultcollid) &&
3777 40 : fselect->resulttype == exprType(fld) &&
3778 40 : fselect->resulttypmod == exprTypmod(fld) &&
3779 20 : fselect->resultcollid == exprCollation(fld))
3780 20 : return fld;
3781 : }
3782 : }
3783 24879 : newfselect = makeNode(FieldSelect);
3784 24879 : newfselect->arg = (Expr *) arg;
3785 24879 : newfselect->fieldnum = fselect->fieldnum;
3786 24879 : newfselect->resulttype = fselect->resulttype;
3787 24879 : newfselect->resulttypmod = fselect->resulttypmod;
3788 24879 : newfselect->resultcollid = fselect->resultcollid;
3789 24879 : if (arg && IsA(arg, Const))
3790 : {
3791 509 : Const *con = (Const *) arg;
3792 :
3793 509 : if (rowtype_field_matches(con->consttype,
3794 509 : newfselect->fieldnum,
3795 : newfselect->resulttype,
3796 : newfselect->resulttypmod,
3797 : newfselect->resultcollid))
3798 509 : return ece_evaluate_expr(newfselect);
3799 : }
3800 24370 : return (Node *) newfselect;
3801 : }
3802 28006 : case T_NullTest:
3803 : {
3804 28006 : NullTest *ntest = (NullTest *) node;
3805 : NullTest *newntest;
3806 : Node *arg;
3807 :
3808 28006 : arg = eval_const_expressions_mutator((Node *) ntest->arg,
3809 : context);
3810 28005 : if (ntest->argisrow && arg && IsA(arg, RowExpr))
3811 : {
3812 : /*
3813 : * We break ROW(...) IS [NOT] NULL into separate tests on
3814 : * its component fields. This form is usually more
3815 : * efficient to evaluate, as well as being more amenable
3816 : * to optimization.
3817 : */
3818 37 : RowExpr *rarg = (RowExpr *) arg;
3819 37 : List *newargs = NIL;
3820 : ListCell *l;
3821 :
3822 136 : foreach(l, rarg->args)
3823 : {
3824 99 : Node *relem = (Node *) lfirst(l);
3825 :
3826 : /*
3827 : * A constant field refutes the whole NullTest if it's
3828 : * of the wrong nullness; else we can discard it.
3829 : */
3830 99 : if (relem && IsA(relem, Const))
3831 0 : {
3832 0 : Const *carg = (Const *) relem;
3833 :
3834 0 : if (carg->constisnull ?
3835 0 : (ntest->nulltesttype == IS_NOT_NULL) :
3836 0 : (ntest->nulltesttype == IS_NULL))
3837 0 : return makeBoolConst(false, false);
3838 0 : continue;
3839 : }
3840 :
3841 : /*
3842 : * A proven non-nullable field refutes the whole
3843 : * NullTest if the test is IS NULL; else we can
3844 : * discard it.
3845 : */
3846 198 : if (relem &&
3847 99 : expr_is_nonnullable(context->root, (Expr *) relem,
3848 : NOTNULL_SOURCE_HASHTABLE))
3849 : {
3850 0 : if (ntest->nulltesttype == IS_NULL)
3851 0 : return makeBoolConst(false, false);
3852 0 : continue;
3853 : }
3854 :
3855 : /*
3856 : * Else, make a scalar (argisrow == false) NullTest
3857 : * for this field. Scalar semantics are required
3858 : * because IS [NOT] NULL doesn't recurse; see comments
3859 : * in ExecEvalRowNullInt().
3860 : */
3861 99 : newntest = makeNode(NullTest);
3862 99 : newntest->arg = (Expr *) relem;
3863 99 : newntest->nulltesttype = ntest->nulltesttype;
3864 99 : newntest->argisrow = false;
3865 99 : newntest->location = ntest->location;
3866 99 : newargs = lappend(newargs, newntest);
3867 : }
3868 : /* If all the inputs were constants, result is TRUE */
3869 37 : if (newargs == NIL)
3870 0 : return makeBoolConst(true, false);
3871 : /* If only one nonconst input, it's the result */
3872 37 : if (list_length(newargs) == 1)
3873 0 : return (Node *) linitial(newargs);
3874 : /* Else we need an AND node */
3875 37 : return (Node *) make_andclause(newargs);
3876 : }
3877 27968 : if (!ntest->argisrow && arg && IsA(arg, Const))
3878 : {
3879 281 : Const *carg = (Const *) arg;
3880 : bool result;
3881 :
3882 281 : switch (ntest->nulltesttype)
3883 : {
3884 238 : case IS_NULL:
3885 238 : result = carg->constisnull;
3886 238 : break;
3887 43 : case IS_NOT_NULL:
3888 43 : result = !carg->constisnull;
3889 43 : break;
3890 0 : default:
3891 0 : elog(ERROR, "unrecognized nulltesttype: %d",
3892 : (int) ntest->nulltesttype);
3893 : result = false; /* keep compiler quiet */
3894 : break;
3895 : }
3896 :
3897 281 : return makeBoolConst(result, false);
3898 : }
3899 55032 : if (!ntest->argisrow && arg &&
3900 27345 : expr_is_nonnullable(context->root, (Expr *) arg,
3901 : NOTNULL_SOURCE_HASHTABLE))
3902 : {
3903 : bool result;
3904 :
3905 536 : switch (ntest->nulltesttype)
3906 : {
3907 128 : case IS_NULL:
3908 128 : result = false;
3909 128 : break;
3910 408 : case IS_NOT_NULL:
3911 408 : result = true;
3912 408 : break;
3913 0 : default:
3914 0 : elog(ERROR, "unrecognized nulltesttype: %d",
3915 : (int) ntest->nulltesttype);
3916 : result = false; /* keep compiler quiet */
3917 : break;
3918 : }
3919 :
3920 536 : return makeBoolConst(result, false);
3921 : }
3922 :
3923 27151 : newntest = makeNode(NullTest);
3924 27151 : newntest->arg = (Expr *) arg;
3925 27151 : newntest->nulltesttype = ntest->nulltesttype;
3926 27151 : newntest->argisrow = ntest->argisrow;
3927 27151 : newntest->location = ntest->location;
3928 27151 : return (Node *) newntest;
3929 : }
3930 1659 : case T_BooleanTest:
3931 : {
3932 : /*
3933 : * This case could be folded into the generic handling used
3934 : * for ArrayExpr etc. But because the simplification logic is
3935 : * so trivial, applying evaluate_expr() to perform it would be
3936 : * a heavy overhead. BooleanTest is probably common enough to
3937 : * justify keeping this bespoke implementation.
3938 : */
3939 1659 : BooleanTest *btest = (BooleanTest *) node;
3940 : BooleanTest *newbtest;
3941 : Node *arg;
3942 :
3943 1659 : arg = eval_const_expressions_mutator((Node *) btest->arg,
3944 : context);
3945 1659 : if (arg && IsA(arg, Const))
3946 : {
3947 : /*
3948 : * If arg is Const, simplify to constant.
3949 : */
3950 185 : Const *carg = (Const *) arg;
3951 : bool result;
3952 :
3953 185 : switch (btest->booltesttype)
3954 : {
3955 0 : case IS_TRUE:
3956 0 : result = (!carg->constisnull &&
3957 0 : DatumGetBool(carg->constvalue));
3958 0 : break;
3959 185 : case IS_NOT_TRUE:
3960 370 : result = (carg->constisnull ||
3961 185 : !DatumGetBool(carg->constvalue));
3962 185 : break;
3963 0 : case IS_FALSE:
3964 0 : result = (!carg->constisnull &&
3965 0 : !DatumGetBool(carg->constvalue));
3966 0 : break;
3967 0 : case IS_NOT_FALSE:
3968 0 : result = (carg->constisnull ||
3969 0 : DatumGetBool(carg->constvalue));
3970 0 : break;
3971 0 : case IS_UNKNOWN:
3972 0 : result = carg->constisnull;
3973 0 : break;
3974 0 : case IS_NOT_UNKNOWN:
3975 0 : result = !carg->constisnull;
3976 0 : break;
3977 0 : default:
3978 0 : elog(ERROR, "unrecognized booltesttype: %d",
3979 : (int) btest->booltesttype);
3980 : result = false; /* keep compiler quiet */
3981 : break;
3982 : }
3983 :
3984 185 : return makeBoolConst(result, false);
3985 : }
3986 2948 : if (arg &&
3987 1474 : expr_is_nonnullable(context->root, (Expr *) arg,
3988 : NOTNULL_SOURCE_HASHTABLE))
3989 : {
3990 : /*
3991 : * If arg is proven non-nullable, simplify to boolean
3992 : * expression or constant.
3993 : */
3994 67 : switch (btest->booltesttype)
3995 : {
3996 20 : case IS_TRUE:
3997 : case IS_NOT_FALSE:
3998 20 : return arg;
3999 :
4000 27 : case IS_FALSE:
4001 : case IS_NOT_TRUE:
4002 27 : return (Node *) make_notclause((Expr *) arg);
4003 :
4004 10 : case IS_UNKNOWN:
4005 10 : return makeBoolConst(false, false);
4006 :
4007 10 : case IS_NOT_UNKNOWN:
4008 10 : return makeBoolConst(true, false);
4009 :
4010 0 : default:
4011 0 : elog(ERROR, "unrecognized booltesttype: %d",
4012 : (int) btest->booltesttype);
4013 : break;
4014 : }
4015 : }
4016 :
4017 1407 : newbtest = makeNode(BooleanTest);
4018 1407 : newbtest->arg = (Expr *) arg;
4019 1407 : newbtest->booltesttype = btest->booltesttype;
4020 1407 : newbtest->location = btest->location;
4021 1407 : return (Node *) newbtest;
4022 : }
4023 18504 : case T_CoerceToDomain:
4024 : {
4025 : /*
4026 : * If the domain currently has no constraints, we replace the
4027 : * CoerceToDomain node with a simple RelabelType, which is
4028 : * both far faster to execute and more amenable to later
4029 : * optimization. We must then mark the plan as needing to be
4030 : * rebuilt if the domain's constraints change.
4031 : *
4032 : * Also, in estimation mode, always replace CoerceToDomain
4033 : * nodes, effectively assuming that the coercion will succeed.
4034 : */
4035 18504 : CoerceToDomain *cdomain = (CoerceToDomain *) node;
4036 : CoerceToDomain *newcdomain;
4037 : Node *arg;
4038 :
4039 18504 : arg = eval_const_expressions_mutator((Node *) cdomain->arg,
4040 : context);
4041 18484 : if (context->estimate ||
4042 18444 : !DomainHasConstraints(cdomain->resulttype, NULL))
4043 : {
4044 : /* Record dependency, if this isn't estimation mode */
4045 12273 : if (context->root && !context->estimate)
4046 12189 : record_plan_type_dependency(context->root,
4047 : cdomain->resulttype);
4048 :
4049 : /* Generate RelabelType to substitute for CoerceToDomain */
4050 12273 : return applyRelabelType(arg,
4051 : cdomain->resulttype,
4052 : cdomain->resulttypmod,
4053 : cdomain->resultcollid,
4054 : cdomain->coercionformat,
4055 : cdomain->location,
4056 : true);
4057 : }
4058 :
4059 6211 : newcdomain = makeNode(CoerceToDomain);
4060 6211 : newcdomain->arg = (Expr *) arg;
4061 6211 : newcdomain->resulttype = cdomain->resulttype;
4062 6211 : newcdomain->resulttypmod = cdomain->resulttypmod;
4063 6211 : newcdomain->resultcollid = cdomain->resultcollid;
4064 6211 : newcdomain->coercionformat = cdomain->coercionformat;
4065 6211 : newcdomain->location = cdomain->location;
4066 6211 : return (Node *) newcdomain;
4067 : }
4068 3657 : case T_PlaceHolderVar:
4069 :
4070 : /*
4071 : * In estimation mode, just strip the PlaceHolderVar node
4072 : * altogether; this amounts to estimating that the contained value
4073 : * won't be forced to null by an outer join. In regular mode we
4074 : * just use the default behavior (ie, simplify the expression but
4075 : * leave the PlaceHolderVar node intact).
4076 : */
4077 3657 : if (context->estimate)
4078 : {
4079 700 : PlaceHolderVar *phv = (PlaceHolderVar *) node;
4080 :
4081 700 : return eval_const_expressions_mutator((Node *) phv->phexpr,
4082 : context);
4083 : }
4084 2957 : break;
4085 75 : case T_ConvertRowtypeExpr:
4086 : {
4087 75 : ConvertRowtypeExpr *cre = castNode(ConvertRowtypeExpr, node);
4088 : Node *arg;
4089 : ConvertRowtypeExpr *newcre;
4090 :
4091 75 : arg = eval_const_expressions_mutator((Node *) cre->arg,
4092 : context);
4093 :
4094 75 : newcre = makeNode(ConvertRowtypeExpr);
4095 75 : newcre->resulttype = cre->resulttype;
4096 75 : newcre->convertformat = cre->convertformat;
4097 75 : newcre->location = cre->location;
4098 :
4099 : /*
4100 : * In case of a nested ConvertRowtypeExpr, we can convert the
4101 : * leaf row directly to the topmost row format without any
4102 : * intermediate conversions. (This works because
4103 : * ConvertRowtypeExpr is used only for child->parent
4104 : * conversion in inheritance trees, which works by exact match
4105 : * of column name, and a column absent in an intermediate
4106 : * result can't be present in the final result.)
4107 : *
4108 : * No need to check more than one level deep, because the
4109 : * above recursion will have flattened anything else.
4110 : */
4111 75 : if (arg != NULL && IsA(arg, ConvertRowtypeExpr))
4112 : {
4113 10 : ConvertRowtypeExpr *argcre = (ConvertRowtypeExpr *) arg;
4114 :
4115 10 : arg = (Node *) argcre->arg;
4116 :
4117 : /*
4118 : * Make sure an outer implicit conversion can't hide an
4119 : * inner explicit one.
4120 : */
4121 10 : if (newcre->convertformat == COERCE_IMPLICIT_CAST)
4122 0 : newcre->convertformat = argcre->convertformat;
4123 : }
4124 :
4125 75 : newcre->arg = (Expr *) arg;
4126 :
4127 75 : if (arg != NULL && IsA(arg, Const))
4128 15 : return ece_evaluate_expr((Node *) newcre);
4129 60 : return (Node *) newcre;
4130 : }
4131 5187361 : default:
4132 5187361 : break;
4133 : }
4134 :
4135 : /*
4136 : * For any node type not handled above, copy the node unchanged but
4137 : * const-simplify its subexpressions. This is the correct thing for node
4138 : * types whose behavior might change between planning and execution, such
4139 : * as CurrentOfExpr. It's also a safe default for new node types not
4140 : * known to this routine.
4141 : */
4142 5190318 : return ece_generic_processing(node);
4143 : }
4144 :
4145 : /*
4146 : * Subroutine for eval_const_expressions: check for non-Const nodes.
4147 : *
4148 : * We can abort recursion immediately on finding a non-Const node. This is
4149 : * critical for performance, else eval_const_expressions_mutator would take
4150 : * O(N^2) time on non-simplifiable trees. However, we do need to descend
4151 : * into List nodes since expression_tree_walker sometimes invokes the walker
4152 : * function directly on List subtrees.
4153 : */
4154 : static bool
4155 166204 : contain_non_const_walker(Node *node, void *context)
4156 : {
4157 166204 : if (node == NULL)
4158 596 : return false;
4159 165608 : if (IsA(node, Const))
4160 85316 : return false;
4161 80292 : if (IsA(node, List))
4162 26391 : return expression_tree_walker(node, contain_non_const_walker, context);
4163 : /* Otherwise, abort the tree traversal and return true */
4164 53901 : return true;
4165 : }
4166 :
4167 : /*
4168 : * Subroutine for eval_const_expressions: check if a function is OK to evaluate
4169 : */
4170 : static bool
4171 300 : ece_function_is_safe(Oid funcid, eval_const_expressions_context *context)
4172 : {
4173 300 : char provolatile = func_volatile(funcid);
4174 :
4175 : /*
4176 : * Ordinarily we are only allowed to simplify immutable functions. But for
4177 : * purposes of estimation, we consider it okay to simplify functions that
4178 : * are merely stable; the risk that the result might change from planning
4179 : * time to execution time is worth taking in preference to not being able
4180 : * to estimate the value at all.
4181 : */
4182 300 : if (provolatile == PROVOLATILE_IMMUTABLE)
4183 300 : return true;
4184 0 : if (context->estimate && provolatile == PROVOLATILE_STABLE)
4185 0 : return true;
4186 0 : return false;
4187 : }
4188 :
4189 : /*
4190 : * Subroutine for eval_const_expressions: process arguments of an OR clause
4191 : *
4192 : * This includes flattening of nested ORs as well as recursion to
4193 : * eval_const_expressions to simplify the OR arguments.
4194 : *
4195 : * After simplification, OR arguments are handled as follows:
4196 : * non constant: keep
4197 : * FALSE: drop (does not affect result)
4198 : * TRUE: force result to TRUE
4199 : * NULL: keep only one
4200 : * We must keep one NULL input because OR expressions evaluate to NULL when no
4201 : * input is TRUE and at least one is NULL. We don't actually include the NULL
4202 : * here, that's supposed to be done by the caller.
4203 : *
4204 : * The output arguments *haveNull and *forceTrue must be initialized false
4205 : * by the caller. They will be set true if a NULL constant or TRUE constant,
4206 : * respectively, is detected anywhere in the argument list.
4207 : */
4208 : static List *
4209 15299 : simplify_or_arguments(List *args,
4210 : eval_const_expressions_context *context,
4211 : bool *haveNull, bool *forceTrue)
4212 : {
4213 15299 : List *newargs = NIL;
4214 : List *unprocessed_args;
4215 :
4216 : /*
4217 : * We want to ensure that any OR immediately beneath another OR gets
4218 : * flattened into a single OR-list, so as to simplify later reasoning.
4219 : *
4220 : * To avoid stack overflow from recursion of eval_const_expressions, we
4221 : * resort to some tenseness here: we keep a list of not-yet-processed
4222 : * inputs, and handle flattening of nested ORs by prepending to the to-do
4223 : * list instead of recursing. Now that the parser generates N-argument
4224 : * ORs from simple lists, this complexity is probably less necessary than
4225 : * it once was, but we might as well keep the logic.
4226 : */
4227 15299 : unprocessed_args = list_copy(args);
4228 49600 : while (unprocessed_args)
4229 : {
4230 34407 : Node *arg = (Node *) linitial(unprocessed_args);
4231 :
4232 34407 : unprocessed_args = list_delete_first(unprocessed_args);
4233 :
4234 : /* flatten nested ORs as per above comment */
4235 34407 : if (is_orclause(arg))
4236 7 : {
4237 7 : List *subargs = ((BoolExpr *) arg)->args;
4238 7 : List *oldlist = unprocessed_args;
4239 :
4240 7 : unprocessed_args = list_concat_copy(subargs, unprocessed_args);
4241 : /* perhaps-overly-tense code to avoid leaking old lists */
4242 7 : list_free(oldlist);
4243 7 : continue;
4244 : }
4245 :
4246 : /* If it's not an OR, simplify it */
4247 34400 : arg = eval_const_expressions_mutator(arg, context);
4248 :
4249 : /*
4250 : * It is unlikely but not impossible for simplification of a non-OR
4251 : * clause to produce an OR. Recheck, but don't be too tense about it
4252 : * since it's not a mainstream case. In particular we don't worry
4253 : * about const-simplifying the input twice, nor about list leakage.
4254 : */
4255 34400 : if (is_orclause(arg))
4256 0 : {
4257 0 : List *subargs = ((BoolExpr *) arg)->args;
4258 :
4259 0 : unprocessed_args = list_concat_copy(subargs, unprocessed_args);
4260 0 : continue;
4261 : }
4262 :
4263 : /*
4264 : * OK, we have a const-simplified non-OR argument. Process it per
4265 : * comments above.
4266 : */
4267 34400 : if (IsA(arg, Const))
4268 3949 : {
4269 4055 : Const *const_input = (Const *) arg;
4270 :
4271 4055 : if (const_input->constisnull)
4272 3813 : *haveNull = true;
4273 242 : else if (DatumGetBool(const_input->constvalue))
4274 : {
4275 106 : *forceTrue = true;
4276 :
4277 : /*
4278 : * Once we detect a TRUE result we can just exit the loop
4279 : * immediately. However, if we ever add a notion of
4280 : * non-removable functions, we'd need to keep scanning.
4281 : */
4282 106 : return NIL;
4283 : }
4284 : /* otherwise, we can drop the constant-false input */
4285 3949 : continue;
4286 : }
4287 :
4288 : /* else emit the simplified arg into the result list */
4289 30345 : newargs = lappend(newargs, arg);
4290 : }
4291 :
4292 15193 : return newargs;
4293 : }
4294 :
4295 : /*
4296 : * Subroutine for eval_const_expressions: process arguments of an AND clause
4297 : *
4298 : * This includes flattening of nested ANDs as well as recursion to
4299 : * eval_const_expressions to simplify the AND arguments.
4300 : *
4301 : * After simplification, AND arguments are handled as follows:
4302 : * non constant: keep
4303 : * TRUE: drop (does not affect result)
4304 : * FALSE: force result to FALSE
4305 : * NULL: keep only one
4306 : * We must keep one NULL input because AND expressions evaluate to NULL when
4307 : * no input is FALSE and at least one is NULL. We don't actually include the
4308 : * NULL here, that's supposed to be done by the caller.
4309 : *
4310 : * The output arguments *haveNull and *forceFalse must be initialized false
4311 : * by the caller. They will be set true if a null constant or false constant,
4312 : * respectively, is detected anywhere in the argument list.
4313 : */
4314 : static List *
4315 116372 : simplify_and_arguments(List *args,
4316 : eval_const_expressions_context *context,
4317 : bool *haveNull, bool *forceFalse)
4318 : {
4319 116372 : List *newargs = NIL;
4320 : List *unprocessed_args;
4321 :
4322 : /* See comments in simplify_or_arguments */
4323 116372 : unprocessed_args = list_copy(args);
4324 423337 : while (unprocessed_args)
4325 : {
4326 307610 : Node *arg = (Node *) linitial(unprocessed_args);
4327 :
4328 307610 : unprocessed_args = list_delete_first(unprocessed_args);
4329 :
4330 : /* flatten nested ANDs as per above comment */
4331 307610 : if (is_andclause(arg))
4332 4021 : {
4333 4021 : List *subargs = ((BoolExpr *) arg)->args;
4334 4021 : List *oldlist = unprocessed_args;
4335 :
4336 4021 : unprocessed_args = list_concat_copy(subargs, unprocessed_args);
4337 : /* perhaps-overly-tense code to avoid leaking old lists */
4338 4021 : list_free(oldlist);
4339 4021 : continue;
4340 : }
4341 :
4342 : /* If it's not an AND, simplify it */
4343 303589 : arg = eval_const_expressions_mutator(arg, context);
4344 :
4345 : /*
4346 : * It is unlikely but not impossible for simplification of a non-AND
4347 : * clause to produce an AND. Recheck, but don't be too tense about it
4348 : * since it's not a mainstream case. In particular we don't worry
4349 : * about const-simplifying the input twice, nor about list leakage.
4350 : */
4351 303589 : if (is_andclause(arg))
4352 30 : {
4353 30 : List *subargs = ((BoolExpr *) arg)->args;
4354 :
4355 30 : unprocessed_args = list_concat_copy(subargs, unprocessed_args);
4356 30 : continue;
4357 : }
4358 :
4359 : /*
4360 : * OK, we have a const-simplified non-AND argument. Process it per
4361 : * comments above.
4362 : */
4363 303559 : if (IsA(arg, Const))
4364 1238 : {
4365 1883 : Const *const_input = (Const *) arg;
4366 :
4367 1883 : if (const_input->constisnull)
4368 35 : *haveNull = true;
4369 1848 : else if (!DatumGetBool(const_input->constvalue))
4370 : {
4371 645 : *forceFalse = true;
4372 :
4373 : /*
4374 : * Once we detect a FALSE result we can just exit the loop
4375 : * immediately. However, if we ever add a notion of
4376 : * non-removable functions, we'd need to keep scanning.
4377 : */
4378 645 : return NIL;
4379 : }
4380 : /* otherwise, we can drop the constant-true input */
4381 1238 : continue;
4382 : }
4383 :
4384 : /* else emit the simplified arg into the result list */
4385 301676 : newargs = lappend(newargs, arg);
4386 : }
4387 :
4388 115727 : return newargs;
4389 : }
4390 :
4391 : /*
4392 : * Subroutine for eval_const_expressions: try to simplify boolean equality
4393 : * or inequality condition
4394 : *
4395 : * Inputs are the operator OID and the simplified arguments to the operator.
4396 : * Returns a simplified expression if successful, or NULL if cannot
4397 : * simplify the expression.
4398 : *
4399 : * The idea here is to reduce "x = true" to "x" and "x = false" to "NOT x",
4400 : * or similarly "x <> true" to "NOT x" and "x <> false" to "x".
4401 : * This is only marginally useful in itself, but doing it in constant folding
4402 : * ensures that we will recognize these forms as being equivalent in, for
4403 : * example, partial index matching.
4404 : *
4405 : * We come here only if simplify_function has failed; therefore we cannot
4406 : * see two constant inputs, nor a constant-NULL input.
4407 : */
4408 : static Node *
4409 1753 : simplify_boolean_equality(Oid opno, List *args)
4410 : {
4411 : Node *leftop;
4412 : Node *rightop;
4413 :
4414 : Assert(list_length(args) == 2);
4415 1753 : leftop = linitial(args);
4416 1753 : rightop = lsecond(args);
4417 1753 : if (leftop && IsA(leftop, Const))
4418 : {
4419 : Assert(!((Const *) leftop)->constisnull);
4420 0 : if (opno == BooleanEqualOperator)
4421 : {
4422 0 : if (DatumGetBool(((Const *) leftop)->constvalue))
4423 0 : return rightop; /* true = foo */
4424 : else
4425 0 : return negate_clause(rightop); /* false = foo */
4426 : }
4427 : else
4428 : {
4429 0 : if (DatumGetBool(((Const *) leftop)->constvalue))
4430 0 : return negate_clause(rightop); /* true <> foo */
4431 : else
4432 0 : return rightop; /* false <> foo */
4433 : }
4434 : }
4435 1753 : if (rightop && IsA(rightop, Const))
4436 : {
4437 : Assert(!((Const *) rightop)->constisnull);
4438 1268 : if (opno == BooleanEqualOperator)
4439 : {
4440 1213 : if (DatumGetBool(((Const *) rightop)->constvalue))
4441 178 : return leftop; /* foo = true */
4442 : else
4443 1035 : return negate_clause(leftop); /* foo = false */
4444 : }
4445 : else
4446 : {
4447 55 : if (DatumGetBool(((Const *) rightop)->constvalue))
4448 50 : return negate_clause(leftop); /* foo <> true */
4449 : else
4450 5 : return leftop; /* foo <> false */
4451 : }
4452 : }
4453 485 : return NULL;
4454 : }
4455 :
4456 : /*
4457 : * Subroutine for eval_const_expressions: try to simplify a function call
4458 : * (which might originally have been an operator; we don't care)
4459 : *
4460 : * Inputs are the function OID, actual result type OID (which is needed for
4461 : * polymorphic functions), result typmod, result collation, the input
4462 : * collation to use for the function, the original argument list (not
4463 : * const-simplified yet, unless process_args is false), and some flags;
4464 : * also the context data for eval_const_expressions.
4465 : *
4466 : * Returns a simplified expression if successful, or NULL if cannot
4467 : * simplify the function call.
4468 : *
4469 : * This function is also responsible for converting named-notation argument
4470 : * lists into positional notation and/or adding any needed default argument
4471 : * expressions; which is a bit grotty, but it avoids extra fetches of the
4472 : * function's pg_proc tuple. For this reason, the args list is
4473 : * pass-by-reference. Conversion and const-simplification of the args list
4474 : * will be done even if simplification of the function call itself is not
4475 : * possible.
4476 : */
4477 : static Expr *
4478 960501 : simplify_function(Oid funcid, Oid result_type, int32 result_typmod,
4479 : Oid result_collid, Oid input_collid, List **args_p,
4480 : bool funcvariadic, bool process_args, bool allow_non_const,
4481 : eval_const_expressions_context *context)
4482 : {
4483 960501 : List *args = *args_p;
4484 : HeapTuple func_tuple;
4485 : Form_pg_proc func_form;
4486 : Expr *newexpr;
4487 :
4488 : /*
4489 : * We have three strategies for simplification: execute the function to
4490 : * deliver a constant result, use a transform function to generate a
4491 : * substitute node tree, or expand in-line the body of the function
4492 : * definition (which only works for simple SQL-language functions, but
4493 : * that is a common case). Each case needs access to the function's
4494 : * pg_proc tuple, so fetch it just once.
4495 : *
4496 : * Note: the allow_non_const flag suppresses both the second and third
4497 : * strategies; so if !allow_non_const, simplify_function can only return a
4498 : * Const or NULL. Argument-list rewriting happens anyway, though.
4499 : */
4500 960501 : func_tuple = SearchSysCache1(PROCOID, ObjectIdGetDatum(funcid));
4501 960501 : if (!HeapTupleIsValid(func_tuple))
4502 0 : elog(ERROR, "cache lookup failed for function %u", funcid);
4503 960501 : func_form = (Form_pg_proc) GETSTRUCT(func_tuple);
4504 :
4505 : /*
4506 : * Process the function arguments, unless the caller did it already.
4507 : *
4508 : * Here we must deal with named or defaulted arguments, and then
4509 : * recursively apply eval_const_expressions to the whole argument list.
4510 : */
4511 960501 : if (process_args)
4512 : {
4513 958668 : args = expand_function_arguments(args, false, result_type, func_tuple);
4514 958668 : args = (List *) expression_tree_mutator((Node *) args,
4515 : eval_const_expressions_mutator,
4516 : context);
4517 : /* Argument processing done, give it back to the caller */
4518 958591 : *args_p = args;
4519 : }
4520 :
4521 : /* Now attempt simplification of the function call proper. */
4522 :
4523 960424 : newexpr = evaluate_function(funcid, result_type, result_typmod,
4524 : result_collid, input_collid,
4525 : args, funcvariadic,
4526 : func_tuple, context);
4527 :
4528 957803 : if (!newexpr && allow_non_const && OidIsValid(func_form->prosupport))
4529 : {
4530 : /*
4531 : * Build a SupportRequestSimplify node to pass to the support
4532 : * function, pointing to a dummy FuncExpr node containing the
4533 : * simplified arg list. We use this approach to present a uniform
4534 : * interface to the support function regardless of how the target
4535 : * function is actually being invoked.
4536 : */
4537 : SupportRequestSimplify req;
4538 : FuncExpr fexpr;
4539 :
4540 27061 : fexpr.xpr.type = T_FuncExpr;
4541 27061 : fexpr.funcid = funcid;
4542 27061 : fexpr.funcresulttype = result_type;
4543 27061 : fexpr.funcretset = func_form->proretset;
4544 27061 : fexpr.funcvariadic = funcvariadic;
4545 27061 : fexpr.funcformat = COERCE_EXPLICIT_CALL;
4546 27061 : fexpr.funccollid = result_collid;
4547 27061 : fexpr.inputcollid = input_collid;
4548 27061 : fexpr.args = args;
4549 27061 : fexpr.location = -1;
4550 :
4551 27061 : req.type = T_SupportRequestSimplify;
4552 27061 : req.root = context->root;
4553 27061 : req.fcall = &fexpr;
4554 :
4555 : newexpr = (Expr *)
4556 27061 : DatumGetPointer(OidFunctionCall1(func_form->prosupport,
4557 : PointerGetDatum(&req)));
4558 :
4559 : /* catch a possible API misunderstanding */
4560 : Assert(newexpr != (Expr *) &fexpr);
4561 : }
4562 :
4563 957803 : if (!newexpr && allow_non_const)
4564 826043 : newexpr = inline_function(funcid, result_type, result_collid,
4565 : input_collid, args, funcvariadic,
4566 : func_tuple, context);
4567 :
4568 957794 : ReleaseSysCache(func_tuple);
4569 :
4570 957794 : return newexpr;
4571 : }
4572 :
4573 : /*
4574 : * simplify_aggref
4575 : * Call the Aggref.aggfnoid's prosupport function to allow it to
4576 : * determine if simplification of the Aggref is possible. Returns the
4577 : * newly simplified node if conversion took place; otherwise, returns the
4578 : * original Aggref.
4579 : *
4580 : * See SupportRequestSimplifyAggref comments in supportnodes.h for further
4581 : * details.
4582 : */
4583 : static Node *
4584 37908 : simplify_aggref(Aggref *aggref, eval_const_expressions_context *context)
4585 : {
4586 37908 : Oid prosupport = get_func_support(aggref->aggfnoid);
4587 :
4588 37908 : if (OidIsValid(prosupport))
4589 : {
4590 : SupportRequestSimplifyAggref req;
4591 : Node *newnode;
4592 :
4593 : /*
4594 : * Build a SupportRequestSimplifyAggref node to pass to the support
4595 : * function.
4596 : */
4597 13890 : req.type = T_SupportRequestSimplifyAggref;
4598 13890 : req.root = context->root;
4599 13890 : req.aggref = aggref;
4600 :
4601 13890 : newnode = (Node *) DatumGetPointer(OidFunctionCall1(prosupport,
4602 : PointerGetDatum(&req)));
4603 :
4604 : /*
4605 : * We expect the support function to return either a new Node or NULL
4606 : * (when simplification isn't possible).
4607 : */
4608 : Assert(newnode != (Node *) aggref || newnode == NULL);
4609 :
4610 13890 : if (newnode != NULL)
4611 274 : return newnode;
4612 : }
4613 :
4614 37634 : return (Node *) aggref;
4615 : }
4616 :
4617 : /*
4618 : * var_is_nonnullable: check to see if the Var cannot be NULL
4619 : *
4620 : * If the Var is defined NOT NULL and meanwhile is not nulled by any outer
4621 : * joins or grouping sets, then we can know that it cannot be NULL.
4622 : *
4623 : * "source" specifies where we should look for NOT NULL proofs.
4624 : */
4625 : bool
4626 25522 : var_is_nonnullable(PlannerInfo *root, Var *var, NotNullSource source)
4627 : {
4628 : Assert(IsA(var, Var));
4629 :
4630 : /* skip upper-level Vars */
4631 25522 : if (var->varlevelsup != 0)
4632 55 : return false;
4633 :
4634 : /* could the Var be nulled by any outer joins or grouping sets? */
4635 25467 : if (!bms_is_empty(var->varnullingrels))
4636 3539 : return false;
4637 :
4638 : /* system columns cannot be NULL */
4639 21928 : if (var->varattno < 0)
4640 30 : return true;
4641 :
4642 : /* we don't trust whole-row Vars */
4643 21898 : if (var->varattno == 0)
4644 48 : return false;
4645 :
4646 : /* Check if the Var is defined as NOT NULL. */
4647 21850 : switch (source)
4648 : {
4649 6242 : case NOTNULL_SOURCE_RELOPT:
4650 : {
4651 : /*
4652 : * We retrieve the column NOT NULL constraint information from
4653 : * the corresponding RelOptInfo.
4654 : */
4655 : RelOptInfo *rel;
4656 : Bitmapset *notnullattnums;
4657 :
4658 6242 : rel = find_base_rel(root, var->varno);
4659 6242 : notnullattnums = rel->notnullattnums;
4660 :
4661 6242 : return bms_is_member(var->varattno, notnullattnums);
4662 : }
4663 15503 : case NOTNULL_SOURCE_HASHTABLE:
4664 : {
4665 : /*
4666 : * We retrieve the column NOT NULL constraint information from
4667 : * the hash table.
4668 : */
4669 : RangeTblEntry *rte;
4670 : Bitmapset *notnullattnums;
4671 :
4672 15503 : rte = planner_rt_fetch(var->varno, root);
4673 :
4674 : /* We can only reason about ordinary relations */
4675 15503 : if (rte->rtekind != RTE_RELATION)
4676 1435 : return false;
4677 :
4678 : /*
4679 : * We must skip inheritance parent tables, as some child
4680 : * tables may have a NOT NULL constraint for a column while
4681 : * others may not. This cannot happen with partitioned
4682 : * tables, though.
4683 : */
4684 14068 : if (rte->inh && rte->relkind != RELKIND_PARTITIONED_TABLE)
4685 175 : return false;
4686 :
4687 13893 : notnullattnums = find_relation_notnullatts(root, rte->relid);
4688 :
4689 13893 : return bms_is_member(var->varattno, notnullattnums);
4690 : }
4691 105 : case NOTNULL_SOURCE_SYSCACHE:
4692 : {
4693 : /*
4694 : * We look up the "attnotnull" field in the attribute
4695 : * relation.
4696 : */
4697 : RangeTblEntry *rte;
4698 :
4699 105 : rte = planner_rt_fetch(var->varno, root);
4700 :
4701 : /* We can only reason about ordinary relations */
4702 105 : if (rte->rtekind != RTE_RELATION)
4703 0 : return false;
4704 :
4705 : /*
4706 : * We must skip inheritance parent tables, as some child
4707 : * tables may have a NOT NULL constraint for a column while
4708 : * others may not. This cannot happen with partitioned
4709 : * tables, though.
4710 : *
4711 : * Note that we need to check if the relation actually has any
4712 : * children, as we might not have done that yet.
4713 : */
4714 105 : if (rte->inh && has_subclass(rte->relid) &&
4715 0 : rte->relkind != RELKIND_PARTITIONED_TABLE)
4716 0 : return false;
4717 :
4718 105 : return get_attnotnull(rte->relid, var->varattno);
4719 : }
4720 0 : default:
4721 0 : elog(ERROR, "unrecognized NotNullSource: %d",
4722 : (int) source);
4723 : break;
4724 : }
4725 :
4726 : return false;
4727 : }
4728 :
4729 : /*
4730 : * expr_is_nonnullable: check to see if the Expr cannot be NULL
4731 : *
4732 : * Returns true iff the given 'expr' cannot produce SQL NULLs.
4733 : *
4734 : * source: specifies where we should look for NOT NULL proofs for Vars.
4735 : * - NOTNULL_SOURCE_RELOPT: Used when RelOptInfos have been generated. We
4736 : * retrieve nullability information directly from the RelOptInfo corresponding
4737 : * to the Var.
4738 : * - NOTNULL_SOURCE_HASHTABLE: Used when RelOptInfos are not yet available,
4739 : * but we have already collected relation-level not-null constraints into the
4740 : * global hash table.
4741 : * - NOTNULL_SOURCE_SYSCACHE: Used for raw parse trees where neither
4742 : * RelOptInfos nor the hash table are available. In this case, we have to
4743 : * look up the 'attnotnull' field directly in the system catalogs.
4744 : *
4745 : * For now, we support only a limited set of expression types. Support for
4746 : * additional node types can be added in the future.
4747 : */
4748 : bool
4749 42139 : expr_is_nonnullable(PlannerInfo *root, Expr *expr, NotNullSource source)
4750 : {
4751 : /* since this function recurses, it could be driven to stack overflow */
4752 42139 : check_stack_depth();
4753 :
4754 42139 : switch (nodeTag(expr))
4755 : {
4756 37342 : case T_Var:
4757 : {
4758 37342 : if (root)
4759 25522 : return var_is_nonnullable(root, (Var *) expr, source);
4760 : }
4761 11820 : break;
4762 394 : case T_Const:
4763 394 : return !((Const *) expr)->constisnull;
4764 165 : case T_CoalesceExpr:
4765 : {
4766 : /*
4767 : * A CoalesceExpr returns NULL if and only if all its
4768 : * arguments are NULL. Therefore, we can determine that a
4769 : * CoalesceExpr cannot be NULL if at least one of its
4770 : * arguments can be proven non-nullable.
4771 : */
4772 165 : CoalesceExpr *coalesceexpr = (CoalesceExpr *) expr;
4773 :
4774 570 : foreach_ptr(Expr, arg, coalesceexpr->args)
4775 : {
4776 330 : if (expr_is_nonnullable(root, arg, source))
4777 45 : return true;
4778 : }
4779 : }
4780 120 : break;
4781 15 : case T_MinMaxExpr:
4782 : {
4783 : /*
4784 : * Like CoalesceExpr, a MinMaxExpr returns NULL only if all
4785 : * its arguments evaluate to NULL.
4786 : */
4787 15 : MinMaxExpr *minmaxexpr = (MinMaxExpr *) expr;
4788 :
4789 50 : foreach_ptr(Expr, arg, minmaxexpr->args)
4790 : {
4791 30 : if (expr_is_nonnullable(root, arg, source))
4792 5 : return true;
4793 : }
4794 : }
4795 10 : break;
4796 81 : case T_CaseExpr:
4797 : {
4798 : /*
4799 : * A CASE expression is non-nullable if all branch results are
4800 : * non-nullable. We must also verify that the default result
4801 : * (ELSE) exists and is non-nullable.
4802 : */
4803 81 : CaseExpr *caseexpr = (CaseExpr *) expr;
4804 :
4805 : /* The default result must be present and non-nullable */
4806 81 : if (caseexpr->defresult == NULL ||
4807 81 : !expr_is_nonnullable(root, caseexpr->defresult, source))
4808 66 : return false;
4809 :
4810 : /* All branch results must be non-nullable */
4811 25 : foreach_ptr(CaseWhen, casewhen, caseexpr->args)
4812 : {
4813 15 : if (!expr_is_nonnullable(root, casewhen->result, source))
4814 10 : return false;
4815 : }
4816 :
4817 5 : return true;
4818 : }
4819 : break;
4820 5 : case T_ArrayExpr:
4821 : {
4822 : /*
4823 : * An ARRAY[] expression always returns a valid Array object,
4824 : * even if it is empty (ARRAY[]) or contains NULLs
4825 : * (ARRAY[NULL]). It never evaluates to a SQL NULL.
4826 : */
4827 5 : return true;
4828 : }
4829 7 : case T_NullTest:
4830 : {
4831 : /*
4832 : * An IS NULL / IS NOT NULL expression always returns a
4833 : * boolean value. It never returns SQL NULL.
4834 : */
4835 7 : return true;
4836 : }
4837 5 : case T_BooleanTest:
4838 : {
4839 : /*
4840 : * A BooleanTest expression always evaluates to a boolean
4841 : * value. It never returns SQL NULL.
4842 : */
4843 5 : return true;
4844 : }
4845 5 : case T_DistinctExpr:
4846 : {
4847 : /*
4848 : * IS DISTINCT FROM never returns NULL, effectively acting as
4849 : * though NULL were a normal data value.
4850 : */
4851 5 : return true;
4852 : }
4853 53 : case T_RelabelType:
4854 : {
4855 : /*
4856 : * RelabelType does not change the nullability of the data.
4857 : * The result is non-nullable if and only if the argument is
4858 : * non-nullable.
4859 : */
4860 53 : return expr_is_nonnullable(root, ((RelabelType *) expr)->arg,
4861 : source);
4862 : }
4863 4067 : default:
4864 4067 : break;
4865 : }
4866 :
4867 16017 : return false;
4868 : }
4869 :
4870 : /*
4871 : * expand_function_arguments: convert named-notation args to positional args
4872 : * and/or insert default args, as needed
4873 : *
4874 : * Returns a possibly-transformed version of the args list.
4875 : *
4876 : * If include_out_arguments is true, then the args list and the result
4877 : * include OUT arguments.
4878 : *
4879 : * The expected result type of the call must be given, for sanity-checking
4880 : * purposes. Also, we ask the caller to provide the function's actual
4881 : * pg_proc tuple, not just its OID.
4882 : *
4883 : * If we need to change anything, the input argument list is copied, not
4884 : * modified.
4885 : *
4886 : * Note: this gets applied to operator argument lists too, even though the
4887 : * cases it handles should never occur there. This should be OK since it
4888 : * will fall through very quickly if there's nothing to do.
4889 : */
4890 : List *
4891 962009 : expand_function_arguments(List *args, bool include_out_arguments,
4892 : Oid result_type, HeapTuple func_tuple)
4893 : {
4894 962009 : Form_pg_proc funcform = (Form_pg_proc) GETSTRUCT(func_tuple);
4895 962009 : Oid *proargtypes = funcform->proargtypes.values;
4896 962009 : int pronargs = funcform->pronargs;
4897 962009 : bool has_named_args = false;
4898 : ListCell *lc;
4899 :
4900 : /*
4901 : * If we are asked to match to OUT arguments, then use the proallargtypes
4902 : * array (which includes those); otherwise use proargtypes (which
4903 : * doesn't). Of course, if proallargtypes is null, we always use
4904 : * proargtypes. (Fetching proallargtypes is annoyingly expensive
4905 : * considering that we may have nothing to do here, but fortunately the
4906 : * common case is include_out_arguments == false.)
4907 : */
4908 962009 : if (include_out_arguments)
4909 : {
4910 : Datum proallargtypes;
4911 : bool isNull;
4912 :
4913 289 : proallargtypes = SysCacheGetAttr(PROCOID, func_tuple,
4914 : Anum_pg_proc_proallargtypes,
4915 : &isNull);
4916 289 : if (!isNull)
4917 : {
4918 118 : ArrayType *arr = DatumGetArrayTypeP(proallargtypes);
4919 :
4920 118 : pronargs = ARR_DIMS(arr)[0];
4921 118 : if (ARR_NDIM(arr) != 1 ||
4922 118 : pronargs < 0 ||
4923 118 : ARR_HASNULL(arr) ||
4924 118 : ARR_ELEMTYPE(arr) != OIDOID)
4925 0 : elog(ERROR, "proallargtypes is not a 1-D Oid array or it contains nulls");
4926 : Assert(pronargs >= funcform->pronargs);
4927 118 : proargtypes = (Oid *) ARR_DATA_PTR(arr);
4928 : }
4929 : }
4930 :
4931 : /* Do we have any named arguments? */
4932 2653404 : foreach(lc, args)
4933 : {
4934 1700817 : Node *arg = (Node *) lfirst(lc);
4935 :
4936 1700817 : if (IsA(arg, NamedArgExpr))
4937 : {
4938 9422 : has_named_args = true;
4939 9422 : break;
4940 : }
4941 : }
4942 :
4943 : /* If so, we must apply reorder_function_arguments */
4944 962009 : if (has_named_args)
4945 : {
4946 9422 : args = reorder_function_arguments(args, pronargs, func_tuple);
4947 : /* Recheck argument types and add casts if needed */
4948 9422 : recheck_cast_function_args(args, result_type,
4949 : proargtypes, pronargs,
4950 : func_tuple);
4951 : }
4952 952587 : else if (list_length(args) < pronargs)
4953 : {
4954 : /* No named args, but we seem to be short some defaults */
4955 5581 : args = add_function_defaults(args, pronargs, func_tuple);
4956 : /* Recheck argument types and add casts if needed */
4957 5581 : recheck_cast_function_args(args, result_type,
4958 : proargtypes, pronargs,
4959 : func_tuple);
4960 : }
4961 :
4962 962009 : return args;
4963 : }
4964 :
4965 : /*
4966 : * reorder_function_arguments: convert named-notation args to positional args
4967 : *
4968 : * This function also inserts default argument values as needed, since it's
4969 : * impossible to form a truly valid positional call without that.
4970 : */
4971 : static List *
4972 9422 : reorder_function_arguments(List *args, int pronargs, HeapTuple func_tuple)
4973 : {
4974 9422 : Form_pg_proc funcform = (Form_pg_proc) GETSTRUCT(func_tuple);
4975 9422 : int nargsprovided = list_length(args);
4976 : Node *argarray[FUNC_MAX_ARGS];
4977 : ListCell *lc;
4978 : int i;
4979 :
4980 : Assert(nargsprovided <= pronargs);
4981 9422 : if (pronargs < 0 || pronargs > FUNC_MAX_ARGS)
4982 0 : elog(ERROR, "too many function arguments");
4983 9422 : memset(argarray, 0, pronargs * sizeof(Node *));
4984 :
4985 : /* Deconstruct the argument list into an array indexed by argnumber */
4986 9422 : i = 0;
4987 38156 : foreach(lc, args)
4988 : {
4989 28734 : Node *arg = (Node *) lfirst(lc);
4990 :
4991 28734 : if (!IsA(arg, NamedArgExpr))
4992 : {
4993 : /* positional argument, assumed to precede all named args */
4994 : Assert(argarray[i] == NULL);
4995 1842 : argarray[i++] = arg;
4996 : }
4997 : else
4998 : {
4999 26892 : NamedArgExpr *na = (NamedArgExpr *) arg;
5000 :
5001 : Assert(na->argnumber >= 0 && na->argnumber < pronargs);
5002 : Assert(argarray[na->argnumber] == NULL);
5003 26892 : argarray[na->argnumber] = (Node *) na->arg;
5004 : }
5005 : }
5006 :
5007 : /*
5008 : * Fetch default expressions, if needed, and insert into array at proper
5009 : * locations (they aren't necessarily consecutive or all used)
5010 : */
5011 9422 : if (nargsprovided < pronargs)
5012 : {
5013 4467 : List *defaults = fetch_function_defaults(func_tuple);
5014 :
5015 4467 : i = pronargs - funcform->pronargdefaults;
5016 24888 : foreach(lc, defaults)
5017 : {
5018 20421 : if (argarray[i] == NULL)
5019 8879 : argarray[i] = (Node *) lfirst(lc);
5020 20421 : i++;
5021 : }
5022 : }
5023 :
5024 : /* Now reconstruct the args list in proper order */
5025 9422 : args = NIL;
5026 47035 : for (i = 0; i < pronargs; i++)
5027 : {
5028 : Assert(argarray[i] != NULL);
5029 37613 : args = lappend(args, argarray[i]);
5030 : }
5031 :
5032 9422 : return args;
5033 : }
5034 :
5035 : /*
5036 : * add_function_defaults: add missing function arguments from its defaults
5037 : *
5038 : * This is used only when the argument list was positional to begin with,
5039 : * and so we know we just need to add defaults at the end.
5040 : */
5041 : static List *
5042 5581 : add_function_defaults(List *args, int pronargs, HeapTuple func_tuple)
5043 : {
5044 5581 : int nargsprovided = list_length(args);
5045 : List *defaults;
5046 : int ndelete;
5047 :
5048 : /* Get all the default expressions from the pg_proc tuple */
5049 5581 : defaults = fetch_function_defaults(func_tuple);
5050 :
5051 : /* Delete any unused defaults from the list */
5052 5581 : ndelete = nargsprovided + list_length(defaults) - pronargs;
5053 5581 : if (ndelete < 0)
5054 0 : elog(ERROR, "not enough default arguments");
5055 5581 : if (ndelete > 0)
5056 179 : defaults = list_delete_first_n(defaults, ndelete);
5057 :
5058 : /* And form the combined argument list, not modifying the input list */
5059 5581 : return list_concat_copy(args, defaults);
5060 : }
5061 :
5062 : /*
5063 : * fetch_function_defaults: get function's default arguments as expression list
5064 : */
5065 : static List *
5066 10048 : fetch_function_defaults(HeapTuple func_tuple)
5067 : {
5068 : List *defaults;
5069 : Datum proargdefaults;
5070 : char *str;
5071 :
5072 10048 : proargdefaults = SysCacheGetAttrNotNull(PROCOID, func_tuple,
5073 : Anum_pg_proc_proargdefaults);
5074 10048 : str = TextDatumGetCString(proargdefaults);
5075 10048 : defaults = castNode(List, stringToNode(str));
5076 10048 : pfree(str);
5077 10048 : return defaults;
5078 : }
5079 :
5080 : /*
5081 : * recheck_cast_function_args: recheck function args and typecast as needed
5082 : * after adding defaults.
5083 : *
5084 : * It is possible for some of the defaulted arguments to be polymorphic;
5085 : * therefore we can't assume that the default expressions have the correct
5086 : * data types already. We have to re-resolve polymorphics and do coercion
5087 : * just like the parser did.
5088 : *
5089 : * This should be a no-op if there are no polymorphic arguments,
5090 : * but we do it anyway to be sure.
5091 : *
5092 : * Note: if any casts are needed, the args list is modified in-place;
5093 : * caller should have already copied the list structure.
5094 : */
5095 : static void
5096 15003 : recheck_cast_function_args(List *args, Oid result_type,
5097 : Oid *proargtypes, int pronargs,
5098 : HeapTuple func_tuple)
5099 : {
5100 15003 : Form_pg_proc funcform = (Form_pg_proc) GETSTRUCT(func_tuple);
5101 : int nargs;
5102 : Oid actual_arg_types[FUNC_MAX_ARGS];
5103 : Oid declared_arg_types[FUNC_MAX_ARGS];
5104 : Oid rettype;
5105 : ListCell *lc;
5106 :
5107 15003 : if (list_length(args) > FUNC_MAX_ARGS)
5108 0 : elog(ERROR, "too many function arguments");
5109 15003 : nargs = 0;
5110 73123 : foreach(lc, args)
5111 : {
5112 58120 : actual_arg_types[nargs++] = exprType((Node *) lfirst(lc));
5113 : }
5114 : Assert(nargs == pronargs);
5115 15003 : memcpy(declared_arg_types, proargtypes, pronargs * sizeof(Oid));
5116 15003 : rettype = enforce_generic_type_consistency(actual_arg_types,
5117 : declared_arg_types,
5118 : nargs,
5119 : funcform->prorettype,
5120 : false);
5121 : /* let's just check we got the same answer as the parser did ... */
5122 15003 : if (rettype != result_type)
5123 0 : elog(ERROR, "function's resolved result type changed during planning");
5124 :
5125 : /* perform any necessary typecasting of arguments */
5126 15003 : make_fn_arguments(NULL, args, actual_arg_types, declared_arg_types);
5127 15003 : }
5128 :
5129 : /*
5130 : * evaluate_function: try to pre-evaluate a function call
5131 : *
5132 : * We can do this if the function is strict and has any constant-null inputs
5133 : * (just return a null constant), or if the function is immutable and has all
5134 : * constant inputs (call it and return the result as a Const node). In
5135 : * estimation mode we are willing to pre-evaluate stable functions too.
5136 : *
5137 : * Returns a simplified expression if successful, or NULL if cannot
5138 : * simplify the function.
5139 : */
5140 : static Expr *
5141 960424 : evaluate_function(Oid funcid, Oid result_type, int32 result_typmod,
5142 : Oid result_collid, Oid input_collid, List *args,
5143 : bool funcvariadic,
5144 : HeapTuple func_tuple,
5145 : eval_const_expressions_context *context)
5146 : {
5147 960424 : Form_pg_proc funcform = (Form_pg_proc) GETSTRUCT(func_tuple);
5148 960424 : bool has_nonconst_input = false;
5149 960424 : bool has_null_input = false;
5150 : ListCell *arg;
5151 : FuncExpr *newexpr;
5152 :
5153 : /*
5154 : * Can't simplify if it returns a set.
5155 : */
5156 960424 : if (funcform->proretset)
5157 45967 : return NULL;
5158 :
5159 : /*
5160 : * Can't simplify if it returns RECORD. The immediate problem is that it
5161 : * will be needing an expected tupdesc which we can't supply here.
5162 : *
5163 : * In the case where it has OUT parameters, we could build an expected
5164 : * tupdesc from those, but there may be other gotchas lurking. In
5165 : * particular, if the function were to return NULL, we would produce a
5166 : * null constant with no remaining indication of which concrete record
5167 : * type it is. For now, seems best to leave the function call unreduced.
5168 : */
5169 914457 : if (funcform->prorettype == RECORDOID)
5170 4014 : return NULL;
5171 :
5172 : /*
5173 : * Check for constant inputs and especially constant-NULL inputs.
5174 : */
5175 2534538 : foreach(arg, args)
5176 : {
5177 1624095 : if (IsA(lfirst(arg), Const))
5178 718886 : has_null_input |= ((Const *) lfirst(arg))->constisnull;
5179 : else
5180 905209 : has_nonconst_input = true;
5181 : }
5182 :
5183 : /*
5184 : * If the function is strict and has a constant-NULL input, it will never
5185 : * be called at all, so we can replace the call by a NULL constant, even
5186 : * if there are other inputs that aren't constant, and even if the
5187 : * function is not otherwise immutable.
5188 : */
5189 910443 : if (funcform->proisstrict && has_null_input)
5190 4363 : return (Expr *) makeNullConst(result_type, result_typmod,
5191 : result_collid);
5192 :
5193 : /*
5194 : * Otherwise, can simplify only if all inputs are constants. (For a
5195 : * non-strict function, constant NULL inputs are treated the same as
5196 : * constant non-NULL inputs.)
5197 : */
5198 906080 : if (has_nonconst_input)
5199 689135 : return NULL;
5200 :
5201 : /*
5202 : * Ordinarily we are only allowed to simplify immutable functions. But for
5203 : * purposes of estimation, we consider it okay to simplify functions that
5204 : * are merely stable; the risk that the result might change from planning
5205 : * time to execution time is worth taking in preference to not being able
5206 : * to estimate the value at all.
5207 : */
5208 216945 : if (funcform->provolatile == PROVOLATILE_IMMUTABLE)
5209 : /* okay */ ;
5210 88906 : else if (context->estimate && funcform->provolatile == PROVOLATILE_STABLE)
5211 : /* okay */ ;
5212 : else
5213 87026 : return NULL;
5214 :
5215 : /*
5216 : * OK, looks like we can simplify this operator/function.
5217 : *
5218 : * Build a new FuncExpr node containing the already-simplified arguments.
5219 : */
5220 129919 : newexpr = makeNode(FuncExpr);
5221 129919 : newexpr->funcid = funcid;
5222 129919 : newexpr->funcresulttype = result_type;
5223 129919 : newexpr->funcretset = false;
5224 129919 : newexpr->funcvariadic = funcvariadic;
5225 129919 : newexpr->funcformat = COERCE_EXPLICIT_CALL; /* doesn't matter */
5226 129919 : newexpr->funccollid = result_collid; /* doesn't matter */
5227 129919 : newexpr->inputcollid = input_collid;
5228 129919 : newexpr->args = args;
5229 129919 : newexpr->location = -1;
5230 :
5231 129919 : return evaluate_expr((Expr *) newexpr, result_type, result_typmod,
5232 : result_collid);
5233 : }
5234 :
5235 : /*
5236 : * inline_function: try to expand a function call inline
5237 : *
5238 : * If the function is a sufficiently simple SQL-language function
5239 : * (just "SELECT expression"), then we can inline it and avoid the rather
5240 : * high per-call overhead of SQL functions. Furthermore, this can expose
5241 : * opportunities for constant-folding within the function expression.
5242 : *
5243 : * We have to beware of some special cases however. A directly or
5244 : * indirectly recursive function would cause us to recurse forever,
5245 : * so we keep track of which functions we are already expanding and
5246 : * do not re-expand them. Also, if a parameter is used more than once
5247 : * in the SQL-function body, we require it not to contain any volatile
5248 : * functions (volatiles might deliver inconsistent answers) nor to be
5249 : * unreasonably expensive to evaluate. The expensiveness check not only
5250 : * prevents us from doing multiple evaluations of an expensive parameter
5251 : * at runtime, but is a safety value to limit growth of an expression due
5252 : * to repeated inlining.
5253 : *
5254 : * We must also beware of changing the volatility or strictness status of
5255 : * functions by inlining them.
5256 : *
5257 : * Also, at the moment we can't inline functions returning RECORD. This
5258 : * doesn't work in the general case because it discards information such
5259 : * as OUT-parameter declarations.
5260 : *
5261 : * Also, context-dependent expression nodes in the argument list are trouble.
5262 : *
5263 : * Returns a simplified expression if successful, or NULL if cannot
5264 : * simplify the function.
5265 : */
5266 : static Expr *
5267 826043 : inline_function(Oid funcid, Oid result_type, Oid result_collid,
5268 : Oid input_collid, List *args,
5269 : bool funcvariadic,
5270 : HeapTuple func_tuple,
5271 : eval_const_expressions_context *context)
5272 : {
5273 826043 : Form_pg_proc funcform = (Form_pg_proc) GETSTRUCT(func_tuple);
5274 : char *src;
5275 : Datum tmp;
5276 : bool isNull;
5277 : MemoryContext oldcxt;
5278 : MemoryContext mycxt;
5279 : inline_error_callback_arg callback_arg;
5280 : ErrorContextCallback sqlerrcontext;
5281 : FuncExpr *fexpr;
5282 : SQLFunctionParseInfoPtr pinfo;
5283 : TupleDesc rettupdesc;
5284 : ParseState *pstate;
5285 : List *raw_parsetree_list;
5286 : List *querytree_list;
5287 : Query *querytree;
5288 : Node *newexpr;
5289 : int *usecounts;
5290 : ListCell *arg;
5291 : int i;
5292 :
5293 : /*
5294 : * Forget it if the function is not SQL-language or has other showstopper
5295 : * properties. (The prokind and nargs checks are just paranoia.)
5296 : */
5297 826043 : if (funcform->prolang != SQLlanguageId ||
5298 7501 : funcform->prokind != PROKIND_FUNCTION ||
5299 7501 : funcform->prosecdef ||
5300 7491 : funcform->proretset ||
5301 6058 : funcform->prorettype == RECORDOID ||
5302 11571 : !heap_attisnull(func_tuple, Anum_pg_proc_proconfig, NULL) ||
5303 5768 : funcform->pronargs != list_length(args))
5304 820275 : return NULL;
5305 :
5306 : /* Check for recursive function, and give up trying to expand if so */
5307 5768 : if (list_member_oid(context->active_fns, funcid))
5308 10 : return NULL;
5309 :
5310 : /* Check permission to call function (fail later, if not) */
5311 5758 : if (object_aclcheck(ProcedureRelationId, funcid, GetUserId(), ACL_EXECUTE) != ACLCHECK_OK)
5312 13 : return NULL;
5313 :
5314 : /* Check whether a plugin wants to hook function entry/exit */
5315 5745 : if (FmgrHookIsNeeded(funcid))
5316 0 : return NULL;
5317 :
5318 : /*
5319 : * Make a temporary memory context, so that we don't leak all the stuff
5320 : * that parsing might create.
5321 : */
5322 5745 : mycxt = AllocSetContextCreate(CurrentMemoryContext,
5323 : "inline_function",
5324 : ALLOCSET_DEFAULT_SIZES);
5325 5745 : oldcxt = MemoryContextSwitchTo(mycxt);
5326 :
5327 : /*
5328 : * We need a dummy FuncExpr node containing the already-simplified
5329 : * arguments. (In some cases we don't really need it, but building it is
5330 : * cheap enough that it's not worth contortions to avoid.)
5331 : */
5332 5745 : fexpr = makeNode(FuncExpr);
5333 5745 : fexpr->funcid = funcid;
5334 5745 : fexpr->funcresulttype = result_type;
5335 5745 : fexpr->funcretset = false;
5336 5745 : fexpr->funcvariadic = funcvariadic;
5337 5745 : fexpr->funcformat = COERCE_EXPLICIT_CALL; /* doesn't matter */
5338 5745 : fexpr->funccollid = result_collid; /* doesn't matter */
5339 5745 : fexpr->inputcollid = input_collid;
5340 5745 : fexpr->args = args;
5341 5745 : fexpr->location = -1;
5342 :
5343 : /* Fetch the function body */
5344 5745 : tmp = SysCacheGetAttrNotNull(PROCOID, func_tuple, Anum_pg_proc_prosrc);
5345 5745 : src = TextDatumGetCString(tmp);
5346 :
5347 : /*
5348 : * Setup error traceback support for ereport(). This is so that we can
5349 : * finger the function that bad information came from.
5350 : */
5351 5745 : callback_arg.proname = NameStr(funcform->proname);
5352 5745 : callback_arg.prosrc = src;
5353 :
5354 5745 : sqlerrcontext.callback = sql_inline_error_callback;
5355 5745 : sqlerrcontext.arg = &callback_arg;
5356 5745 : sqlerrcontext.previous = error_context_stack;
5357 5745 : error_context_stack = &sqlerrcontext;
5358 :
5359 : /* If we have prosqlbody, pay attention to that not prosrc */
5360 5745 : tmp = SysCacheGetAttr(PROCOID,
5361 : func_tuple,
5362 : Anum_pg_proc_prosqlbody,
5363 : &isNull);
5364 5745 : if (!isNull)
5365 : {
5366 : Node *n;
5367 : List *query_list;
5368 :
5369 3297 : n = stringToNode(TextDatumGetCString(tmp));
5370 3297 : if (IsA(n, List))
5371 2652 : query_list = linitial_node(List, castNode(List, n));
5372 : else
5373 645 : query_list = list_make1(n);
5374 3297 : if (list_length(query_list) != 1)
5375 5 : goto fail;
5376 3292 : querytree = linitial(query_list);
5377 :
5378 : /*
5379 : * Because we'll insist below that the querytree have an empty rtable
5380 : * and no sublinks, it cannot have any relation references that need
5381 : * to be locked or rewritten. So we can omit those steps.
5382 : */
5383 : }
5384 : else
5385 : {
5386 : /* Set up to handle parameters while parsing the function body. */
5387 2448 : pinfo = prepare_sql_fn_parse_info(func_tuple,
5388 : (Node *) fexpr,
5389 : input_collid);
5390 :
5391 : /*
5392 : * We just do parsing and parse analysis, not rewriting, because
5393 : * rewriting will not affect table-free-SELECT-only queries, which is
5394 : * all that we care about. Also, we can punt as soon as we detect
5395 : * more than one command in the function body.
5396 : */
5397 2448 : raw_parsetree_list = pg_parse_query(src);
5398 2448 : if (list_length(raw_parsetree_list) != 1)
5399 45 : goto fail;
5400 :
5401 2403 : pstate = make_parsestate(NULL);
5402 2403 : pstate->p_sourcetext = src;
5403 2403 : sql_fn_parser_setup(pstate, pinfo);
5404 :
5405 2403 : querytree = transformTopLevelStmt(pstate, linitial(raw_parsetree_list));
5406 :
5407 2399 : free_parsestate(pstate);
5408 : }
5409 :
5410 : /*
5411 : * The single command must be a simple "SELECT expression".
5412 : *
5413 : * Note: if you change the tests involved in this, see also plpgsql's
5414 : * exec_simple_check_plan(). That generally needs to have the same idea
5415 : * of what's a "simple expression", so that inlining a function that
5416 : * previously wasn't inlined won't change plpgsql's conclusion.
5417 : */
5418 5691 : if (!IsA(querytree, Query) ||
5419 5691 : querytree->commandType != CMD_SELECT ||
5420 5590 : querytree->hasAggs ||
5421 5433 : querytree->hasWindowFuncs ||
5422 5433 : querytree->hasTargetSRFs ||
5423 5433 : querytree->hasSubLinks ||
5424 4292 : querytree->cteList ||
5425 4292 : querytree->rtable ||
5426 2730 : querytree->jointree->fromlist ||
5427 2730 : querytree->jointree->quals ||
5428 2730 : querytree->groupClause ||
5429 2730 : querytree->groupingSets ||
5430 2730 : querytree->havingQual ||
5431 2730 : querytree->windowClause ||
5432 2730 : querytree->distinctClause ||
5433 2730 : querytree->sortClause ||
5434 2730 : querytree->limitOffset ||
5435 2730 : querytree->limitCount ||
5436 5352 : querytree->setOperations ||
5437 2676 : list_length(querytree->targetList) != 1)
5438 3065 : goto fail;
5439 :
5440 : /* If the function result is composite, resolve it */
5441 2626 : (void) get_expr_result_type((Node *) fexpr,
5442 : NULL,
5443 : &rettupdesc);
5444 :
5445 : /*
5446 : * Make sure the function (still) returns what it's declared to. This
5447 : * will raise an error if wrong, but that's okay since the function would
5448 : * fail at runtime anyway. Note that check_sql_fn_retval will also insert
5449 : * a coercion if needed to make the tlist expression match the declared
5450 : * type of the function.
5451 : *
5452 : * Note: we do not try this until we have verified that no rewriting was
5453 : * needed; that's probably not important, but let's be careful.
5454 : */
5455 2626 : querytree_list = list_make1(querytree);
5456 2626 : if (check_sql_fn_retval(list_make1(querytree_list),
5457 : result_type, rettupdesc,
5458 2626 : funcform->prokind,
5459 : false))
5460 10 : goto fail; /* reject whole-tuple-result cases */
5461 :
5462 : /*
5463 : * Given the tests above, check_sql_fn_retval shouldn't have decided to
5464 : * inject a projection step, but let's just make sure.
5465 : */
5466 2612 : if (querytree != linitial(querytree_list))
5467 0 : goto fail;
5468 :
5469 : /* Now we can grab the tlist expression */
5470 2612 : newexpr = (Node *) ((TargetEntry *) linitial(querytree->targetList))->expr;
5471 :
5472 : /*
5473 : * If the SQL function returns VOID, we can only inline it if it is a
5474 : * SELECT of an expression returning VOID (ie, it's just a redirection to
5475 : * another VOID-returning function). In all non-VOID-returning cases,
5476 : * check_sql_fn_retval should ensure that newexpr returns the function's
5477 : * declared result type, so this test shouldn't fail otherwise; but we may
5478 : * as well cope gracefully if it does.
5479 : */
5480 2612 : if (exprType(newexpr) != result_type)
5481 15 : goto fail;
5482 :
5483 : /*
5484 : * Additional validity checks on the expression. It mustn't be more
5485 : * volatile than the surrounding function (this is to avoid breaking hacks
5486 : * that involve pretending a function is immutable when it really ain't).
5487 : * If the surrounding function is declared strict, then the expression
5488 : * must contain only strict constructs and must use all of the function
5489 : * parameters (this is overkill, but an exact analysis is hard).
5490 : */
5491 3156 : if (funcform->provolatile == PROVOLATILE_IMMUTABLE &&
5492 559 : contain_mutable_functions(newexpr))
5493 9 : goto fail;
5494 3365 : else if (funcform->provolatile == PROVOLATILE_STABLE &&
5495 777 : contain_volatile_functions(newexpr))
5496 0 : goto fail;
5497 :
5498 3918 : if (funcform->proisstrict &&
5499 1330 : contain_nonstrict_functions(newexpr))
5500 37 : goto fail;
5501 :
5502 : /*
5503 : * If any parameter expression contains a context-dependent node, we can't
5504 : * inline, for fear of putting such a node into the wrong context.
5505 : */
5506 2551 : if (contain_context_dependent_node((Node *) args))
5507 5 : goto fail;
5508 :
5509 : /*
5510 : * We may be able to do it; there are still checks on parameter usage to
5511 : * make, but those are most easily done in combination with the actual
5512 : * substitution of the inputs. So start building expression with inputs
5513 : * substituted.
5514 : */
5515 2546 : usecounts = (int *) palloc0(funcform->pronargs * sizeof(int));
5516 2546 : newexpr = substitute_actual_parameters(newexpr, funcform->pronargs,
5517 : args, usecounts);
5518 :
5519 : /* Now check for parameter usage */
5520 2546 : i = 0;
5521 6793 : foreach(arg, args)
5522 : {
5523 4247 : Node *param = lfirst(arg);
5524 :
5525 4247 : if (usecounts[i] == 0)
5526 : {
5527 : /* Param not used at all: uncool if func is strict */
5528 211 : if (funcform->proisstrict)
5529 0 : goto fail;
5530 : }
5531 4036 : else if (usecounts[i] != 1)
5532 : {
5533 : /* Param used multiple times: uncool if expensive or volatile */
5534 : QualCost eval_cost;
5535 :
5536 : /*
5537 : * We define "expensive" as "contains any subplan or more than 10
5538 : * operators". Note that the subplan search has to be done
5539 : * explicitly, since cost_qual_eval() will barf on unplanned
5540 : * subselects.
5541 : */
5542 281 : if (contain_subplans(param))
5543 0 : goto fail;
5544 281 : cost_qual_eval(&eval_cost, list_make1(param), NULL);
5545 281 : if (eval_cost.startup + eval_cost.per_tuple >
5546 281 : 10 * cpu_operator_cost)
5547 0 : goto fail;
5548 :
5549 : /*
5550 : * Check volatility last since this is more expensive than the
5551 : * above tests
5552 : */
5553 281 : if (contain_volatile_functions(param))
5554 0 : goto fail;
5555 : }
5556 4247 : i++;
5557 : }
5558 :
5559 : /*
5560 : * Whew --- we can make the substitution. Copy the modified expression
5561 : * out of the temporary memory context, and clean up.
5562 : */
5563 2546 : MemoryContextSwitchTo(oldcxt);
5564 :
5565 2546 : newexpr = copyObject(newexpr);
5566 :
5567 2546 : MemoryContextDelete(mycxt);
5568 :
5569 : /*
5570 : * If the result is of a collatable type, force the result to expose the
5571 : * correct collation. In most cases this does not matter, but it's
5572 : * possible that the function result is used directly as a sort key or in
5573 : * other places where we expect exprCollation() to tell the truth.
5574 : */
5575 2546 : if (OidIsValid(result_collid))
5576 : {
5577 1190 : Oid exprcoll = exprCollation(newexpr);
5578 :
5579 1190 : if (OidIsValid(exprcoll) && exprcoll != result_collid)
5580 : {
5581 18 : CollateExpr *newnode = makeNode(CollateExpr);
5582 :
5583 18 : newnode->arg = (Expr *) newexpr;
5584 18 : newnode->collOid = result_collid;
5585 18 : newnode->location = -1;
5586 :
5587 18 : newexpr = (Node *) newnode;
5588 : }
5589 : }
5590 :
5591 : /*
5592 : * Since there is now no trace of the function in the plan tree, we must
5593 : * explicitly record the plan's dependency on the function.
5594 : */
5595 2546 : if (context->root)
5596 2393 : record_plan_function_dependency(context->root, funcid);
5597 :
5598 : /*
5599 : * Recursively try to simplify the modified expression. Here we must add
5600 : * the current function to the context list of active functions.
5601 : */
5602 2546 : context->active_fns = lappend_oid(context->active_fns, funcid);
5603 2546 : newexpr = eval_const_expressions_mutator(newexpr, context);
5604 2545 : context->active_fns = list_delete_last(context->active_fns);
5605 :
5606 2545 : error_context_stack = sqlerrcontext.previous;
5607 :
5608 2545 : return (Expr *) newexpr;
5609 :
5610 : /* Here if func is not inlinable: release temp memory and return NULL */
5611 3191 : fail:
5612 3191 : MemoryContextSwitchTo(oldcxt);
5613 3191 : MemoryContextDelete(mycxt);
5614 3191 : error_context_stack = sqlerrcontext.previous;
5615 :
5616 3191 : return NULL;
5617 : }
5618 :
5619 : /*
5620 : * Replace Param nodes by appropriate actual parameters
5621 : */
5622 : static Node *
5623 2546 : substitute_actual_parameters(Node *expr, int nargs, List *args,
5624 : int *usecounts)
5625 : {
5626 : substitute_actual_parameters_context context;
5627 :
5628 2546 : context.nargs = nargs;
5629 2546 : context.args = args;
5630 2546 : context.usecounts = usecounts;
5631 :
5632 2546 : return substitute_actual_parameters_mutator(expr, &context);
5633 : }
5634 :
5635 : static Node *
5636 14703 : substitute_actual_parameters_mutator(Node *node,
5637 : substitute_actual_parameters_context *context)
5638 : {
5639 14703 : if (node == NULL)
5640 405 : return NULL;
5641 14298 : if (IsA(node, Param))
5642 : {
5643 4335 : Param *param = (Param *) node;
5644 :
5645 4335 : if (param->paramkind != PARAM_EXTERN)
5646 0 : elog(ERROR, "unexpected paramkind: %d", (int) param->paramkind);
5647 4335 : if (param->paramid <= 0 || param->paramid > context->nargs)
5648 0 : elog(ERROR, "invalid paramid: %d", param->paramid);
5649 :
5650 : /* Count usage of parameter */
5651 4335 : context->usecounts[param->paramid - 1]++;
5652 :
5653 : /* Select the appropriate actual arg and replace the Param with it */
5654 : /* We don't need to copy at this time (it'll get done later) */
5655 4335 : return list_nth(context->args, param->paramid - 1);
5656 : }
5657 9963 : return expression_tree_mutator(node, substitute_actual_parameters_mutator, context);
5658 : }
5659 :
5660 : /*
5661 : * error context callback to let us supply a call-stack traceback
5662 : */
5663 : static void
5664 13 : sql_inline_error_callback(void *arg)
5665 : {
5666 13 : inline_error_callback_arg *callback_arg = (inline_error_callback_arg *) arg;
5667 : int syntaxerrposition;
5668 :
5669 : /* If it's a syntax error, convert to internal syntax error report */
5670 13 : syntaxerrposition = geterrposition();
5671 13 : if (syntaxerrposition > 0)
5672 : {
5673 4 : errposition(0);
5674 4 : internalerrposition(syntaxerrposition);
5675 4 : internalerrquery(callback_arg->prosrc);
5676 : }
5677 :
5678 13 : errcontext("SQL function \"%s\" during inlining", callback_arg->proname);
5679 13 : }
5680 :
5681 : /*
5682 : * evaluate_expr: pre-evaluate a constant expression
5683 : *
5684 : * We use the executor's routine ExecEvalExpr() to avoid duplication of
5685 : * code and ensure we get the same result as the executor would get.
5686 : */
5687 : Expr *
5688 156513 : evaluate_expr(Expr *expr, Oid result_type, int32 result_typmod,
5689 : Oid result_collation)
5690 : {
5691 : EState *estate;
5692 : ExprState *exprstate;
5693 : MemoryContext oldcontext;
5694 : Datum const_val;
5695 : bool const_is_null;
5696 : int16 resultTypLen;
5697 : bool resultTypByVal;
5698 :
5699 : /*
5700 : * To use the executor, we need an EState.
5701 : */
5702 156513 : estate = CreateExecutorState();
5703 :
5704 : /* We can use the estate's working context to avoid memory leaks. */
5705 156513 : oldcontext = MemoryContextSwitchTo(estate->es_query_cxt);
5706 :
5707 : /* Make sure any opfuncids are filled in. */
5708 156513 : fix_opfuncids((Node *) expr);
5709 :
5710 : /*
5711 : * Prepare expr for execution. (Note: we can't use ExecPrepareExpr
5712 : * because it'd result in recursively invoking eval_const_expressions.)
5713 : */
5714 156513 : exprstate = ExecInitExpr(expr, NULL);
5715 :
5716 : /*
5717 : * And evaluate it.
5718 : *
5719 : * It is OK to use a default econtext because none of the ExecEvalExpr()
5720 : * code used in this situation will use econtext. That might seem
5721 : * fortuitous, but it's not so unreasonable --- a constant expression does
5722 : * not depend on context, by definition, n'est ce pas?
5723 : */
5724 156497 : const_val = ExecEvalExprSwitchContext(exprstate,
5725 156497 : GetPerTupleExprContext(estate),
5726 : &const_is_null);
5727 :
5728 : /* Get info needed about result datatype */
5729 153864 : get_typlenbyval(result_type, &resultTypLen, &resultTypByVal);
5730 :
5731 : /* Get back to outer memory context */
5732 153864 : MemoryContextSwitchTo(oldcontext);
5733 :
5734 : /*
5735 : * Must copy result out of sub-context used by expression eval.
5736 : *
5737 : * Also, if it's varlena, forcibly detoast it. This protects us against
5738 : * storing TOAST pointers into plans that might outlive the referenced
5739 : * data. (makeConst would handle detoasting anyway, but it's worth a few
5740 : * extra lines here so that we can do the copy and detoast in one step.)
5741 : */
5742 153864 : if (!const_is_null)
5743 : {
5744 148890 : if (resultTypLen == -1)
5745 69979 : const_val = PointerGetDatum(PG_DETOAST_DATUM_COPY(const_val));
5746 : else
5747 78911 : const_val = datumCopy(const_val, resultTypByVal, resultTypLen);
5748 : }
5749 :
5750 : /* Release all the junk we just created */
5751 153864 : FreeExecutorState(estate);
5752 :
5753 : /*
5754 : * Make the constant result node.
5755 : */
5756 153864 : return (Expr *) makeConst(result_type, result_typmod, result_collation,
5757 : resultTypLen,
5758 : const_val, const_is_null,
5759 : resultTypByVal);
5760 : }
5761 :
5762 :
5763 : /*
5764 : * inline_function_in_from
5765 : * Attempt to "inline" a function in the FROM clause.
5766 : *
5767 : * "rte" is an RTE_FUNCTION rangetable entry. If it represents a call of a
5768 : * function that can be inlined, expand the function and return the
5769 : * substitute Query structure. Otherwise, return NULL.
5770 : *
5771 : * We assume that the RTE's expression has already been put through
5772 : * eval_const_expressions(), which among other things will take care of
5773 : * default arguments and named-argument notation.
5774 : *
5775 : * This has a good deal of similarity to inline_function(), but that's
5776 : * for the general-expression case, and there are enough differences to
5777 : * justify separate functions.
5778 : */
5779 : Query *
5780 36132 : inline_function_in_from(PlannerInfo *root, RangeTblEntry *rte)
5781 : {
5782 : RangeTblFunction *rtfunc;
5783 : FuncExpr *fexpr;
5784 : Oid func_oid;
5785 : HeapTuple func_tuple;
5786 : Form_pg_proc funcform;
5787 : MemoryContext oldcxt;
5788 : MemoryContext mycxt;
5789 : Datum tmp;
5790 : char *src;
5791 : inline_error_callback_arg callback_arg;
5792 : ErrorContextCallback sqlerrcontext;
5793 36132 : Query *querytree = NULL;
5794 :
5795 : Assert(rte->rtekind == RTE_FUNCTION);
5796 :
5797 : /*
5798 : * Guard against infinite recursion during expansion by checking for stack
5799 : * overflow. (There's no need to do more.)
5800 : */
5801 36132 : check_stack_depth();
5802 :
5803 : /* Fail if the RTE has ORDINALITY - we don't implement that here. */
5804 36132 : if (rte->funcordinality)
5805 770 : return NULL;
5806 :
5807 : /* Fail if RTE isn't a single, simple FuncExpr */
5808 35362 : if (list_length(rte->functions) != 1)
5809 57 : return NULL;
5810 35305 : rtfunc = (RangeTblFunction *) linitial(rte->functions);
5811 :
5812 35305 : if (!IsA(rtfunc->funcexpr, FuncExpr))
5813 345 : return NULL;
5814 34960 : fexpr = (FuncExpr *) rtfunc->funcexpr;
5815 :
5816 34960 : func_oid = fexpr->funcid;
5817 :
5818 : /*
5819 : * Refuse to inline if the arguments contain any volatile functions or
5820 : * sub-selects. Volatile functions are rejected because inlining may
5821 : * result in the arguments being evaluated multiple times, risking a
5822 : * change in behavior. Sub-selects are rejected partly for implementation
5823 : * reasons (pushing them down another level might change their behavior)
5824 : * and partly because they're likely to be expensive and so multiple
5825 : * evaluation would be bad.
5826 : */
5827 69802 : if (contain_volatile_functions((Node *) fexpr->args) ||
5828 34842 : contain_subplans((Node *) fexpr->args))
5829 282 : return NULL;
5830 :
5831 : /* Check permission to call function (fail later, if not) */
5832 34678 : if (object_aclcheck(ProcedureRelationId, func_oid, GetUserId(), ACL_EXECUTE) != ACLCHECK_OK)
5833 6 : return NULL;
5834 :
5835 : /* Check whether a plugin wants to hook function entry/exit */
5836 34672 : if (FmgrHookIsNeeded(func_oid))
5837 0 : return NULL;
5838 :
5839 : /*
5840 : * OK, let's take a look at the function's pg_proc entry.
5841 : */
5842 34672 : func_tuple = SearchSysCache1(PROCOID, ObjectIdGetDatum(func_oid));
5843 34672 : if (!HeapTupleIsValid(func_tuple))
5844 0 : elog(ERROR, "cache lookup failed for function %u", func_oid);
5845 34672 : funcform = (Form_pg_proc) GETSTRUCT(func_tuple);
5846 :
5847 : /*
5848 : * If the function SETs any configuration parameters, inlining would cause
5849 : * us to miss making those changes.
5850 : */
5851 34672 : if (!heap_attisnull(func_tuple, Anum_pg_proc_proconfig, NULL))
5852 : {
5853 8 : ReleaseSysCache(func_tuple);
5854 8 : return NULL;
5855 : }
5856 :
5857 : /*
5858 : * Make a temporary memory context, so that we don't leak all the stuff
5859 : * that parsing and rewriting might create. If we succeed, we'll copy
5860 : * just the finished query tree back up to the caller's context.
5861 : */
5862 34664 : mycxt = AllocSetContextCreate(CurrentMemoryContext,
5863 : "inline_function_in_from",
5864 : ALLOCSET_DEFAULT_SIZES);
5865 34664 : oldcxt = MemoryContextSwitchTo(mycxt);
5866 :
5867 : /* Fetch the function body */
5868 34664 : tmp = SysCacheGetAttrNotNull(PROCOID, func_tuple, Anum_pg_proc_prosrc);
5869 34664 : src = TextDatumGetCString(tmp);
5870 :
5871 : /*
5872 : * If the function has an attached support function that can handle
5873 : * SupportRequestInlineInFrom, then attempt to inline with that.
5874 : */
5875 34664 : if (funcform->prosupport)
5876 : {
5877 : SupportRequestInlineInFrom req;
5878 :
5879 12896 : req.type = T_SupportRequestInlineInFrom;
5880 12896 : req.root = root;
5881 12896 : req.rtfunc = rtfunc;
5882 12896 : req.proc = func_tuple;
5883 :
5884 : querytree = (Query *)
5885 12896 : DatumGetPointer(OidFunctionCall1(funcform->prosupport,
5886 : PointerGetDatum(&req)));
5887 : }
5888 :
5889 : /*
5890 : * Setup error traceback support for ereport(). This is so that we can
5891 : * finger the function that bad information came from. We don't install
5892 : * this while running the support function, since it'd be likely to do the
5893 : * wrong thing: any parse errors reported during that are very likely not
5894 : * against the raw function source text.
5895 : */
5896 34664 : callback_arg.proname = NameStr(funcform->proname);
5897 34664 : callback_arg.prosrc = src;
5898 :
5899 34664 : sqlerrcontext.callback = sql_inline_error_callback;
5900 34664 : sqlerrcontext.arg = &callback_arg;
5901 34664 : sqlerrcontext.previous = error_context_stack;
5902 34664 : error_context_stack = &sqlerrcontext;
5903 :
5904 : /*
5905 : * If SupportRequestInlineInFrom didn't work, try our built-in inlining
5906 : * mechanism.
5907 : */
5908 34664 : if (!querytree)
5909 34644 : querytree = inline_sql_function_in_from(root, rtfunc, fexpr,
5910 : func_tuple, funcform, src);
5911 :
5912 34660 : if (!querytree)
5913 34455 : goto fail; /* no luck there either, fail */
5914 :
5915 : /*
5916 : * The result had better be a SELECT Query.
5917 : */
5918 : Assert(IsA(querytree, Query));
5919 : Assert(querytree->commandType == CMD_SELECT);
5920 :
5921 : /*
5922 : * Looks good --- substitute parameters into the query.
5923 : */
5924 205 : querytree = substitute_actual_parameters_in_from(querytree,
5925 205 : funcform->pronargs,
5926 : fexpr->args);
5927 :
5928 : /*
5929 : * Copy the modified query out of the temporary memory context, and clean
5930 : * up.
5931 : */
5932 205 : MemoryContextSwitchTo(oldcxt);
5933 :
5934 205 : querytree = copyObject(querytree);
5935 :
5936 205 : MemoryContextDelete(mycxt);
5937 205 : error_context_stack = sqlerrcontext.previous;
5938 205 : ReleaseSysCache(func_tuple);
5939 :
5940 : /*
5941 : * We don't have to fix collations here because the upper query is already
5942 : * parsed, ie, the collations in the RTE are what count.
5943 : */
5944 :
5945 : /*
5946 : * Since there is now no trace of the function in the plan tree, we must
5947 : * explicitly record the plan's dependency on the function.
5948 : */
5949 205 : record_plan_function_dependency(root, func_oid);
5950 :
5951 : /*
5952 : * We must also notice if the inserted query adds a dependency on the
5953 : * calling role due to RLS quals.
5954 : */
5955 205 : if (querytree->hasRowSecurity)
5956 60 : root->glob->dependsOnRole = true;
5957 :
5958 205 : return querytree;
5959 :
5960 : /* Here if func is not inlinable: release temp memory and return NULL */
5961 34455 : fail:
5962 34455 : MemoryContextSwitchTo(oldcxt);
5963 34455 : MemoryContextDelete(mycxt);
5964 34455 : error_context_stack = sqlerrcontext.previous;
5965 34455 : ReleaseSysCache(func_tuple);
5966 :
5967 34455 : return NULL;
5968 : }
5969 :
5970 : /*
5971 : * inline_sql_function_in_from
5972 : *
5973 : * This implements inline_function_in_from for SQL-language functions.
5974 : * Returns NULL if the function couldn't be inlined.
5975 : *
5976 : * The division of labor between here and inline_function_in_from is based
5977 : * on the rule that inline_function_in_from should make all checks that are
5978 : * certain to be required in both this case and the support-function case.
5979 : * Support functions might also want to make checks analogous to the ones
5980 : * made here, but then again they might not, or they might just assume that
5981 : * the function they are attached to can validly be inlined.
5982 : */
5983 : static Query *
5984 34644 : inline_sql_function_in_from(PlannerInfo *root,
5985 : RangeTblFunction *rtfunc,
5986 : FuncExpr *fexpr,
5987 : HeapTuple func_tuple,
5988 : Form_pg_proc funcform,
5989 : const char *src)
5990 : {
5991 : Datum sqlbody;
5992 : bool isNull;
5993 : List *querytree_list;
5994 : Query *querytree;
5995 : TypeFuncClass functypclass;
5996 : TupleDesc rettupdesc;
5997 :
5998 : /*
5999 : * The function must be declared to return a set, else inlining would
6000 : * change the results if the contained SELECT didn't return exactly one
6001 : * row.
6002 : */
6003 34644 : if (!fexpr->funcretset)
6004 5746 : return NULL;
6005 :
6006 : /*
6007 : * Forget it if the function is not SQL-language or has other showstopper
6008 : * properties. In particular it mustn't be declared STRICT, since we
6009 : * couldn't enforce that. It also mustn't be VOLATILE, because that is
6010 : * supposed to cause it to be executed with its own snapshot, rather than
6011 : * sharing the snapshot of the calling query. We also disallow returning
6012 : * SETOF VOID, because inlining would result in exposing the actual result
6013 : * of the function's last SELECT, which should not happen in that case.
6014 : * (Rechecking prokind, proretset, and pronargs is just paranoia.)
6015 : */
6016 28898 : if (funcform->prolang != SQLlanguageId ||
6017 768 : funcform->prokind != PROKIND_FUNCTION ||
6018 768 : funcform->proisstrict ||
6019 718 : funcform->provolatile == PROVOLATILE_VOLATILE ||
6020 194 : funcform->prorettype == VOIDOID ||
6021 189 : funcform->prosecdef ||
6022 189 : !funcform->proretset ||
6023 189 : list_length(fexpr->args) != funcform->pronargs)
6024 28709 : return NULL;
6025 :
6026 : /* If we have prosqlbody, pay attention to that not prosrc */
6027 189 : sqlbody = SysCacheGetAttr(PROCOID,
6028 : func_tuple,
6029 : Anum_pg_proc_prosqlbody,
6030 : &isNull);
6031 189 : if (!isNull)
6032 : {
6033 : Node *n;
6034 :
6035 10 : n = stringToNode(TextDatumGetCString(sqlbody));
6036 10 : if (IsA(n, List))
6037 10 : querytree_list = linitial_node(List, castNode(List, n));
6038 : else
6039 0 : querytree_list = list_make1(n);
6040 10 : if (list_length(querytree_list) != 1)
6041 0 : return NULL;
6042 10 : querytree = linitial(querytree_list);
6043 :
6044 : /* Acquire necessary locks, then apply rewriter. */
6045 10 : AcquireRewriteLocks(querytree, true, false);
6046 10 : querytree_list = pg_rewrite_query(querytree);
6047 10 : if (list_length(querytree_list) != 1)
6048 0 : return NULL;
6049 10 : querytree = linitial(querytree_list);
6050 : }
6051 : else
6052 : {
6053 : SQLFunctionParseInfoPtr pinfo;
6054 : List *raw_parsetree_list;
6055 :
6056 : /*
6057 : * Set up to handle parameters while parsing the function body. We
6058 : * can use the FuncExpr just created as the input for
6059 : * prepare_sql_fn_parse_info.
6060 : */
6061 179 : pinfo = prepare_sql_fn_parse_info(func_tuple,
6062 : (Node *) fexpr,
6063 : fexpr->inputcollid);
6064 :
6065 : /*
6066 : * Parse, analyze, and rewrite (unlike inline_function(), we can't
6067 : * skip rewriting here). We can fail as soon as we find more than one
6068 : * query, though.
6069 : */
6070 179 : raw_parsetree_list = pg_parse_query(src);
6071 179 : if (list_length(raw_parsetree_list) != 1)
6072 0 : return NULL;
6073 :
6074 179 : querytree_list = pg_analyze_and_rewrite_withcb(linitial(raw_parsetree_list),
6075 : src,
6076 : (ParserSetupHook) sql_fn_parser_setup,
6077 : pinfo, NULL);
6078 179 : if (list_length(querytree_list) != 1)
6079 0 : return NULL;
6080 179 : querytree = linitial(querytree_list);
6081 : }
6082 :
6083 : /*
6084 : * Also resolve the actual function result tupdesc, if composite. If we
6085 : * have a coldeflist, believe that; otherwise use get_expr_result_type.
6086 : * (This logic should match ExecInitFunctionScan.)
6087 : */
6088 189 : if (rtfunc->funccolnames != NIL)
6089 : {
6090 19 : functypclass = TYPEFUNC_RECORD;
6091 19 : rettupdesc = BuildDescFromLists(rtfunc->funccolnames,
6092 19 : rtfunc->funccoltypes,
6093 19 : rtfunc->funccoltypmods,
6094 19 : rtfunc->funccolcollations);
6095 : }
6096 : else
6097 170 : functypclass = get_expr_result_type((Node *) fexpr, NULL, &rettupdesc);
6098 :
6099 : /*
6100 : * The single command must be a plain SELECT.
6101 : */
6102 189 : if (!IsA(querytree, Query) ||
6103 189 : querytree->commandType != CMD_SELECT)
6104 0 : return NULL;
6105 :
6106 : /*
6107 : * Make sure the function (still) returns what it's declared to. This
6108 : * will raise an error if wrong, but that's okay since the function would
6109 : * fail at runtime anyway. Note that check_sql_fn_retval will also insert
6110 : * coercions if needed to make the tlist expression(s) match the declared
6111 : * type of the function. We also ask it to insert dummy NULL columns for
6112 : * any dropped columns in rettupdesc, so that the elements of the modified
6113 : * tlist match up to the attribute numbers.
6114 : *
6115 : * If the function returns a composite type, don't inline unless the check
6116 : * shows it's returning a whole tuple result; otherwise what it's
6117 : * returning is a single composite column which is not what we need.
6118 : */
6119 189 : if (!check_sql_fn_retval(list_make1(querytree_list),
6120 : fexpr->funcresulttype, rettupdesc,
6121 189 : funcform->prokind,
6122 75 : true) &&
6123 75 : (functypclass == TYPEFUNC_COMPOSITE ||
6124 75 : functypclass == TYPEFUNC_COMPOSITE_DOMAIN ||
6125 : functypclass == TYPEFUNC_RECORD))
6126 0 : return NULL; /* reject not-whole-tuple-result cases */
6127 :
6128 : /*
6129 : * check_sql_fn_retval might've inserted a projection step, but that's
6130 : * fine; just make sure we use the upper Query.
6131 : */
6132 185 : querytree = linitial_node(Query, querytree_list);
6133 :
6134 185 : return querytree;
6135 : }
6136 :
6137 : /*
6138 : * Replace Param nodes by appropriate actual parameters
6139 : *
6140 : * This is just enough different from substitute_actual_parameters()
6141 : * that it needs its own code.
6142 : */
6143 : static Query *
6144 205 : substitute_actual_parameters_in_from(Query *expr, int nargs, List *args)
6145 : {
6146 : substitute_actual_parameters_in_from_context context;
6147 :
6148 205 : context.nargs = nargs;
6149 205 : context.args = args;
6150 205 : context.sublevels_up = 1;
6151 :
6152 205 : return query_tree_mutator(expr,
6153 : substitute_actual_parameters_in_from_mutator,
6154 : &context,
6155 : 0);
6156 : }
6157 :
6158 : static Node *
6159 7695 : substitute_actual_parameters_in_from_mutator(Node *node,
6160 : substitute_actual_parameters_in_from_context *context)
6161 : {
6162 : Node *result;
6163 :
6164 7695 : if (node == NULL)
6165 4480 : return NULL;
6166 3215 : if (IsA(node, Query))
6167 : {
6168 125 : context->sublevels_up++;
6169 125 : result = (Node *) query_tree_mutator((Query *) node,
6170 : substitute_actual_parameters_in_from_mutator,
6171 : context,
6172 : 0);
6173 125 : context->sublevels_up--;
6174 125 : return result;
6175 : }
6176 3090 : if (IsA(node, Param))
6177 : {
6178 95 : Param *param = (Param *) node;
6179 :
6180 95 : if (param->paramkind == PARAM_EXTERN)
6181 : {
6182 95 : if (param->paramid <= 0 || param->paramid > context->nargs)
6183 0 : elog(ERROR, "invalid paramid: %d", param->paramid);
6184 :
6185 : /*
6186 : * Since the parameter is being inserted into a subquery, we must
6187 : * adjust levels.
6188 : */
6189 95 : result = copyObject(list_nth(context->args, param->paramid - 1));
6190 95 : IncrementVarSublevelsUp(result, context->sublevels_up, 0);
6191 95 : return result;
6192 : }
6193 : }
6194 2995 : return expression_tree_mutator(node,
6195 : substitute_actual_parameters_in_from_mutator,
6196 : context);
6197 : }
6198 :
6199 : /*
6200 : * pull_paramids
6201 : * Returns a Bitmapset containing the paramids of all Params in 'expr'.
6202 : */
6203 : Bitmapset *
6204 1470 : pull_paramids(Expr *expr)
6205 : {
6206 1470 : Bitmapset *result = NULL;
6207 :
6208 1470 : (void) pull_paramids_walker((Node *) expr, &result);
6209 :
6210 1470 : return result;
6211 : }
6212 :
6213 : static bool
6214 3293 : pull_paramids_walker(Node *node, Bitmapset **context)
6215 : {
6216 3293 : if (node == NULL)
6217 10 : return false;
6218 3283 : if (IsA(node, Param))
6219 : {
6220 1521 : Param *param = (Param *) node;
6221 :
6222 1521 : *context = bms_add_member(*context, param->paramid);
6223 1521 : return false;
6224 : }
6225 1762 : return expression_tree_walker(node, pull_paramids_walker, context);
6226 : }
6227 :
6228 : /*
6229 : * Build ScalarArrayOpExpr on top of 'exprs.' 'haveNonConst' indicates
6230 : * whether at least one of the expressions is not Const. When it's false,
6231 : * the array constant is built directly; otherwise, we have to build a child
6232 : * ArrayExpr. The 'exprs' list gets freed if not directly used in the output
6233 : * expression tree.
6234 : */
6235 : ScalarArrayOpExpr *
6236 2933 : make_SAOP_expr(Oid oper, Node *leftexpr, Oid coltype, Oid arraycollid,
6237 : Oid inputcollid, List *exprs, bool haveNonConst)
6238 : {
6239 2933 : Node *arrayNode = NULL;
6240 2933 : ScalarArrayOpExpr *saopexpr = NULL;
6241 2933 : Oid arraytype = get_array_type(coltype);
6242 :
6243 2933 : if (!OidIsValid(arraytype))
6244 0 : return NULL;
6245 :
6246 : /*
6247 : * Assemble an array from the list of constants. It seems more profitable
6248 : * to build a const array. But in the presence of other nodes, we don't
6249 : * have a specific value here and must employ an ArrayExpr instead.
6250 : */
6251 2933 : if (haveNonConst)
6252 : {
6253 84 : ArrayExpr *arrayExpr = makeNode(ArrayExpr);
6254 :
6255 : /* array_collid will be set by parse_collate.c */
6256 84 : arrayExpr->element_typeid = coltype;
6257 84 : arrayExpr->array_typeid = arraytype;
6258 84 : arrayExpr->multidims = false;
6259 84 : arrayExpr->elements = exprs;
6260 84 : arrayExpr->location = -1;
6261 :
6262 84 : arrayNode = (Node *) arrayExpr;
6263 : }
6264 : else
6265 : {
6266 : int16 typlen;
6267 : bool typbyval;
6268 : char typalign;
6269 : Datum *elems;
6270 : bool *nulls;
6271 2849 : int i = 0;
6272 : ArrayType *arrayConst;
6273 2849 : int dims[1] = {list_length(exprs)};
6274 2849 : int lbs[1] = {1};
6275 :
6276 2849 : get_typlenbyvalalign(coltype, &typlen, &typbyval, &typalign);
6277 :
6278 2849 : elems = palloc_array(Datum, list_length(exprs));
6279 2849 : nulls = palloc_array(bool, list_length(exprs));
6280 11801 : foreach_node(Const, value, exprs)
6281 : {
6282 6103 : elems[i] = value->constvalue;
6283 6103 : nulls[i++] = value->constisnull;
6284 : }
6285 :
6286 2849 : arrayConst = construct_md_array(elems, nulls, 1, dims, lbs,
6287 : coltype, typlen, typbyval, typalign);
6288 2849 : arrayNode = (Node *) makeConst(arraytype, -1, arraycollid,
6289 : -1, PointerGetDatum(arrayConst),
6290 : false, false);
6291 :
6292 2849 : pfree(elems);
6293 2849 : pfree(nulls);
6294 2849 : list_free(exprs);
6295 : }
6296 :
6297 : /* Build the SAOP expression node */
6298 2933 : saopexpr = makeNode(ScalarArrayOpExpr);
6299 2933 : saopexpr->opno = oper;
6300 2933 : saopexpr->opfuncid = get_opcode(oper);
6301 2933 : saopexpr->hashfuncid = InvalidOid;
6302 2933 : saopexpr->negfuncid = InvalidOid;
6303 2933 : saopexpr->useOr = true;
6304 2933 : saopexpr->inputcollid = inputcollid;
6305 2933 : saopexpr->args = list_make2(leftexpr, arrayNode);
6306 2933 : saopexpr->location = -1;
6307 :
6308 2933 : return saopexpr;
6309 : }
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