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_language.h"
25 : #include "catalog/pg_operator.h"
26 : #include "catalog/pg_proc.h"
27 : #include "catalog/pg_type.h"
28 : #include "executor/executor.h"
29 : #include "executor/functions.h"
30 : #include "funcapi.h"
31 : #include "miscadmin.h"
32 : #include "nodes/makefuncs.h"
33 : #include "nodes/multibitmapset.h"
34 : #include "nodes/nodeFuncs.h"
35 : #include "nodes/subscripting.h"
36 : #include "nodes/supportnodes.h"
37 : #include "optimizer/clauses.h"
38 : #include "optimizer/cost.h"
39 : #include "optimizer/optimizer.h"
40 : #include "optimizer/pathnode.h"
41 : #include "optimizer/plancat.h"
42 : #include "optimizer/planmain.h"
43 : #include "parser/analyze.h"
44 : #include "parser/parse_coerce.h"
45 : #include "parser/parse_collate.h"
46 : #include "parser/parse_func.h"
47 : #include "parser/parse_oper.h"
48 : #include "parser/parsetree.h"
49 : #include "rewrite/rewriteHandler.h"
50 : #include "rewrite/rewriteManip.h"
51 : #include "tcop/tcopprot.h"
52 : #include "utils/acl.h"
53 : #include "utils/builtins.h"
54 : #include "utils/datum.h"
55 : #include "utils/fmgroids.h"
56 : #include "utils/json.h"
57 : #include "utils/jsonb.h"
58 : #include "utils/jsonpath.h"
59 : #include "utils/lsyscache.h"
60 : #include "utils/memutils.h"
61 : #include "utils/syscache.h"
62 : #include "utils/typcache.h"
63 :
64 : typedef struct
65 : {
66 : ParamListInfo boundParams;
67 : PlannerInfo *root;
68 : List *active_fns;
69 : Node *case_val;
70 : bool estimate;
71 : } eval_const_expressions_context;
72 :
73 : typedef struct
74 : {
75 : int nargs;
76 : List *args;
77 : int *usecounts;
78 : } substitute_actual_parameters_context;
79 :
80 : typedef struct
81 : {
82 : int nargs;
83 : List *args;
84 : int sublevels_up;
85 : } substitute_actual_parameters_in_from_context;
86 :
87 : typedef struct
88 : {
89 : char *proname;
90 : char *prosrc;
91 : } inline_error_callback_arg;
92 :
93 : typedef struct
94 : {
95 : char max_hazard; /* worst proparallel hazard found so far */
96 : char max_interesting; /* worst proparallel hazard of interest */
97 : List *safe_param_ids; /* PARAM_EXEC Param IDs to treat as safe */
98 : } max_parallel_hazard_context;
99 :
100 : static bool contain_agg_clause_walker(Node *node, void *context);
101 : static bool find_window_functions_walker(Node *node, WindowFuncLists *lists);
102 : static bool contain_subplans_walker(Node *node, void *context);
103 : static bool contain_mutable_functions_walker(Node *node, void *context);
104 : static bool contain_volatile_functions_walker(Node *node, void *context);
105 : static bool contain_volatile_functions_not_nextval_walker(Node *node, void *context);
106 : static bool max_parallel_hazard_walker(Node *node,
107 : max_parallel_hazard_context *context);
108 : static bool contain_nonstrict_functions_walker(Node *node, void *context);
109 : static bool contain_exec_param_walker(Node *node, List *param_ids);
110 : static bool contain_context_dependent_node(Node *clause);
111 : static bool contain_context_dependent_node_walker(Node *node, int *flags);
112 : static bool contain_leaked_vars_walker(Node *node, void *context);
113 : static Relids find_nonnullable_rels_walker(Node *node, bool top_level);
114 : static List *find_nonnullable_vars_walker(Node *node, bool top_level);
115 : static bool is_strict_saop(ScalarArrayOpExpr *expr, bool falseOK);
116 : static bool convert_saop_to_hashed_saop_walker(Node *node, void *context);
117 : static Node *eval_const_expressions_mutator(Node *node,
118 : eval_const_expressions_context *context);
119 : static bool contain_non_const_walker(Node *node, void *context);
120 : static bool ece_function_is_safe(Oid funcid,
121 : eval_const_expressions_context *context);
122 : static List *simplify_or_arguments(List *args,
123 : eval_const_expressions_context *context,
124 : bool *haveNull, bool *forceTrue);
125 : static List *simplify_and_arguments(List *args,
126 : eval_const_expressions_context *context,
127 : bool *haveNull, bool *forceFalse);
128 : static Node *simplify_boolean_equality(Oid opno, List *args);
129 : static Expr *simplify_function(Oid funcid,
130 : Oid result_type, int32 result_typmod,
131 : Oid result_collid, Oid input_collid, List **args_p,
132 : bool funcvariadic, bool process_args, bool allow_non_const,
133 : eval_const_expressions_context *context);
134 : static Node *simplify_aggref(Aggref *aggref,
135 : eval_const_expressions_context *context);
136 : static List *reorder_function_arguments(List *args, int pronargs,
137 : HeapTuple func_tuple);
138 : static List *add_function_defaults(List *args, int pronargs,
139 : HeapTuple func_tuple);
140 : static List *fetch_function_defaults(HeapTuple func_tuple);
141 : static void recheck_cast_function_args(List *args, Oid result_type,
142 : Oid *proargtypes, int pronargs,
143 : HeapTuple func_tuple);
144 : static Expr *evaluate_function(Oid funcid, Oid result_type, int32 result_typmod,
145 : Oid result_collid, Oid input_collid, List *args,
146 : bool funcvariadic,
147 : HeapTuple func_tuple,
148 : eval_const_expressions_context *context);
149 : static Expr *inline_function(Oid funcid, Oid result_type, Oid result_collid,
150 : Oid input_collid, List *args,
151 : bool funcvariadic,
152 : HeapTuple func_tuple,
153 : eval_const_expressions_context *context);
154 : static Node *substitute_actual_parameters(Node *expr, int nargs, List *args,
155 : int *usecounts);
156 : static Node *substitute_actual_parameters_mutator(Node *node,
157 : substitute_actual_parameters_context *context);
158 : static void sql_inline_error_callback(void *arg);
159 : static Query *inline_sql_function_in_from(PlannerInfo *root,
160 : RangeTblFunction *rtfunc,
161 : FuncExpr *fexpr,
162 : HeapTuple func_tuple,
163 : Form_pg_proc funcform,
164 : const char *src);
165 : static Query *substitute_actual_parameters_in_from(Query *expr,
166 : int nargs, List *args);
167 : static Node *substitute_actual_parameters_in_from_mutator(Node *node,
168 : substitute_actual_parameters_in_from_context *context);
169 : static bool pull_paramids_walker(Node *node, Bitmapset **context);
170 :
171 :
172 : /*****************************************************************************
173 : * Aggregate-function clause manipulation
174 : *****************************************************************************/
175 :
176 : /*
177 : * contain_agg_clause
178 : * Recursively search for Aggref/GroupingFunc nodes within a clause.
179 : *
180 : * Returns true if any aggregate found.
181 : *
182 : * This does not descend into subqueries, and so should be used only after
183 : * reduction of sublinks to subplans, or in contexts where it's known there
184 : * are no subqueries. There mustn't be outer-aggregate references either.
185 : *
186 : * (If you want something like this but able to deal with subqueries,
187 : * see rewriteManip.c's contain_aggs_of_level().)
188 : */
189 : bool
190 5564 : contain_agg_clause(Node *clause)
191 : {
192 5564 : return contain_agg_clause_walker(clause, NULL);
193 : }
194 :
195 : static bool
196 6725 : contain_agg_clause_walker(Node *node, void *context)
197 : {
198 6725 : if (node == NULL)
199 18 : return false;
200 6707 : if (IsA(node, Aggref))
201 : {
202 : Assert(((Aggref *) node)->agglevelsup == 0);
203 509 : return true; /* abort the tree traversal and return true */
204 : }
205 6198 : if (IsA(node, GroupingFunc))
206 : {
207 : Assert(((GroupingFunc *) node)->agglevelsup == 0);
208 15 : return true; /* abort the tree traversal and return true */
209 : }
210 : Assert(!IsA(node, SubLink));
211 6183 : return expression_tree_walker(node, contain_agg_clause_walker, context);
212 : }
213 :
214 : /*****************************************************************************
215 : * Window-function clause manipulation
216 : *****************************************************************************/
217 :
218 : /*
219 : * contain_window_function
220 : * Recursively search for WindowFunc nodes within a clause.
221 : *
222 : * Since window functions don't have level fields, but are hard-wired to
223 : * be associated with the current query level, this is just the same as
224 : * rewriteManip.c's function.
225 : */
226 : bool
227 4782 : contain_window_function(Node *clause)
228 : {
229 4782 : return contain_windowfuncs(clause);
230 : }
231 :
232 : /*
233 : * find_window_functions
234 : * Locate all the WindowFunc nodes in an expression tree, and organize
235 : * them by winref ID number.
236 : *
237 : * Caller must provide an upper bound on the winref IDs expected in the tree.
238 : */
239 : WindowFuncLists *
240 1341 : find_window_functions(Node *clause, Index maxWinRef)
241 : {
242 1341 : WindowFuncLists *lists = palloc_object(WindowFuncLists);
243 :
244 1341 : lists->numWindowFuncs = 0;
245 1341 : lists->maxWinRef = maxWinRef;
246 1341 : lists->windowFuncs = (List **) palloc0((maxWinRef + 1) * sizeof(List *));
247 1341 : (void) find_window_functions_walker(clause, lists);
248 1341 : return lists;
249 : }
250 :
251 : static bool
252 11329 : find_window_functions_walker(Node *node, WindowFuncLists *lists)
253 : {
254 11329 : if (node == NULL)
255 109 : return false;
256 11220 : if (IsA(node, WindowFunc))
257 : {
258 1854 : WindowFunc *wfunc = (WindowFunc *) node;
259 :
260 : /* winref is unsigned, so one-sided test is OK */
261 1854 : if (wfunc->winref > lists->maxWinRef)
262 0 : elog(ERROR, "WindowFunc contains out-of-range winref %u",
263 : wfunc->winref);
264 :
265 3708 : lists->windowFuncs[wfunc->winref] =
266 1854 : lappend(lists->windowFuncs[wfunc->winref], wfunc);
267 1854 : lists->numWindowFuncs++;
268 :
269 : /*
270 : * We assume that the parser checked that there are no window
271 : * functions in the arguments or filter clause. Hence, we need not
272 : * recurse into them. (If either the parser or the planner screws up
273 : * on this point, the executor will still catch it; see ExecInitExpr.)
274 : */
275 1854 : return false;
276 : }
277 : Assert(!IsA(node, SubLink));
278 9366 : return expression_tree_walker(node, find_window_functions_walker, lists);
279 : }
280 :
281 :
282 : /*****************************************************************************
283 : * Support for expressions returning sets
284 : *****************************************************************************/
285 :
286 : /*
287 : * expression_returns_set_rows
288 : * Estimate the number of rows returned by a set-returning expression.
289 : * The result is 1 if it's not a set-returning expression.
290 : *
291 : * We should only examine the top-level function or operator; it used to be
292 : * appropriate to recurse, but not anymore. (Even if there are more SRFs in
293 : * the function's inputs, their multipliers are accounted for separately.)
294 : *
295 : * Note: keep this in sync with expression_returns_set() in nodes/nodeFuncs.c.
296 : */
297 : double
298 264107 : expression_returns_set_rows(PlannerInfo *root, Node *clause)
299 : {
300 264107 : if (clause == NULL)
301 0 : return 1.0;
302 264107 : if (IsA(clause, FuncExpr))
303 : {
304 34995 : FuncExpr *expr = (FuncExpr *) clause;
305 :
306 34995 : if (expr->funcretset)
307 29902 : return clamp_row_est(get_function_rows(root, expr->funcid, clause));
308 : }
309 234205 : if (IsA(clause, OpExpr))
310 : {
311 1743 : OpExpr *expr = (OpExpr *) clause;
312 :
313 1743 : if (expr->opretset)
314 : {
315 3 : set_opfuncid(expr);
316 3 : return clamp_row_est(get_function_rows(root, expr->opfuncid, clause));
317 : }
318 : }
319 234202 : return 1.0;
320 : }
321 :
322 :
323 : /*****************************************************************************
324 : * Subplan clause manipulation
325 : *****************************************************************************/
326 :
327 : /*
328 : * contain_subplans
329 : * Recursively search for subplan nodes within a clause.
330 : *
331 : * If we see a SubLink node, we will return true. This is only possible if
332 : * the expression tree hasn't yet been transformed by subselect.c. We do not
333 : * know whether the node will produce a true subplan or just an initplan,
334 : * but we make the conservative assumption that it will be a subplan.
335 : *
336 : * Returns true if any subplan found.
337 : */
338 : bool
339 31603 : contain_subplans(Node *clause)
340 : {
341 31603 : return contain_subplans_walker(clause, NULL);
342 : }
343 :
344 : static bool
345 140276 : contain_subplans_walker(Node *node, void *context)
346 : {
347 140276 : if (node == NULL)
348 3981 : return false;
349 136295 : if (IsA(node, SubPlan) ||
350 136244 : IsA(node, AlternativeSubPlan) ||
351 136244 : IsA(node, SubLink))
352 172 : return true; /* abort the tree traversal and return true */
353 136123 : return expression_tree_walker(node, contain_subplans_walker, context);
354 : }
355 :
356 :
357 : /*****************************************************************************
358 : * Check clauses for mutable functions
359 : *****************************************************************************/
360 :
361 : /*
362 : * contain_mutable_functions
363 : * Recursively search for mutable functions within a clause.
364 : *
365 : * Returns true if any mutable function (or operator implemented by a
366 : * mutable function) is found. This test is needed so that we don't
367 : * mistakenly think that something like "WHERE random() < 0.5" can be treated
368 : * as a constant qualification.
369 : *
370 : * This will give the right answer only for clauses that have been put
371 : * through expression preprocessing. Callers outside the planner typically
372 : * should use contain_mutable_functions_after_planning() instead, for the
373 : * reasons given there.
374 : *
375 : * We will recursively look into Query nodes (i.e., SubLink sub-selects)
376 : * but not into SubPlans. See comments for contain_volatile_functions().
377 : */
378 : bool
379 87365 : contain_mutable_functions(Node *clause)
380 : {
381 87365 : return contain_mutable_functions_walker(clause, NULL);
382 : }
383 :
384 : static bool
385 64113 : contain_mutable_functions_checker(Oid func_id, void *context)
386 : {
387 64113 : return (func_volatile(func_id) != PROVOLATILE_IMMUTABLE);
388 : }
389 :
390 : static bool
391 230602 : contain_mutable_functions_walker(Node *node, void *context)
392 : {
393 230602 : if (node == NULL)
394 1164 : return false;
395 : /* Check for mutable functions in node itself */
396 229438 : if (check_functions_in_node(node, contain_mutable_functions_checker,
397 : context))
398 4239 : return true;
399 :
400 225199 : if (IsA(node, JsonConstructorExpr))
401 : {
402 0 : const JsonConstructorExpr *ctor = (JsonConstructorExpr *) node;
403 : ListCell *lc;
404 : bool is_jsonb;
405 :
406 0 : is_jsonb = ctor->returning->format->format_type == JS_FORMAT_JSONB;
407 :
408 : /*
409 : * Check argument_type => json[b] conversions specifically. We still
410 : * recurse to check 'args' below, but here we want to specifically
411 : * check whether or not the emitted clause would fail to be immutable
412 : * because of TimeZone, for example.
413 : */
414 0 : foreach(lc, ctor->args)
415 : {
416 0 : Oid typid = exprType(lfirst(lc));
417 :
418 0 : if (is_jsonb ?
419 0 : !to_jsonb_is_immutable(typid) :
420 0 : !to_json_is_immutable(typid))
421 0 : return true;
422 : }
423 :
424 : /* Check all subnodes */
425 : }
426 :
427 225199 : if (IsA(node, JsonExpr))
428 : {
429 117 : JsonExpr *jexpr = castNode(JsonExpr, node);
430 : Const *cnst;
431 :
432 117 : if (!IsA(jexpr->path_spec, Const))
433 0 : return true;
434 :
435 117 : cnst = castNode(Const, jexpr->path_spec);
436 :
437 : Assert(cnst->consttype == JSONPATHOID);
438 117 : if (cnst->constisnull)
439 0 : return false;
440 :
441 117 : if (jspIsMutable(DatumGetJsonPathP(cnst->constvalue),
442 : jexpr->passing_names, jexpr->passing_values))
443 81 : return true;
444 : }
445 :
446 225118 : if (IsA(node, SQLValueFunction))
447 : {
448 : /* all variants of SQLValueFunction are stable */
449 215 : return true;
450 : }
451 :
452 224903 : if (IsA(node, NextValueExpr))
453 : {
454 : /* NextValueExpr is volatile */
455 0 : return true;
456 : }
457 :
458 : /*
459 : * It should be safe to treat MinMaxExpr as immutable, because it will
460 : * depend on a non-cross-type btree comparison function, and those should
461 : * always be immutable. Treating XmlExpr as immutable is more dubious,
462 : * and treating CoerceToDomain as immutable is outright dangerous. But we
463 : * have done so historically, and changing this would probably cause more
464 : * problems than it would fix. In practice, if you have a non-immutable
465 : * domain constraint you are in for pain anyhow.
466 : */
467 :
468 : /* Recurse to check arguments */
469 224903 : if (IsA(node, Query))
470 : {
471 : /* Recurse into subselects */
472 0 : return query_tree_walker((Query *) node,
473 : contain_mutable_functions_walker,
474 : context, 0);
475 : }
476 224903 : return expression_tree_walker(node, contain_mutable_functions_walker,
477 : context);
478 : }
479 :
480 : /*
481 : * contain_mutable_functions_after_planning
482 : * Test whether given expression contains mutable functions.
483 : *
484 : * This is a wrapper for contain_mutable_functions() that is safe to use from
485 : * outside the planner. The difference is that it first runs the expression
486 : * through expression_planner(). There are two key reasons why we need that:
487 : *
488 : * First, function default arguments will get inserted, which may affect
489 : * volatility (consider "default now()").
490 : *
491 : * Second, inline-able functions will get inlined, which may allow us to
492 : * conclude that the function is really less volatile than it's marked.
493 : * As an example, polymorphic functions must be marked with the most volatile
494 : * behavior that they have for any input type, but once we inline the
495 : * function we may be able to conclude that it's not so volatile for the
496 : * particular input type we're dealing with.
497 : */
498 : bool
499 1718 : contain_mutable_functions_after_planning(Expr *expr)
500 : {
501 : /* We assume here that expression_planner() won't scribble on its input */
502 1718 : expr = expression_planner(expr);
503 :
504 : /* Now we can search for non-immutable functions */
505 1718 : return contain_mutable_functions((Node *) expr);
506 : }
507 :
508 :
509 : /*****************************************************************************
510 : * Check clauses for volatile functions
511 : *****************************************************************************/
512 :
513 : /*
514 : * contain_volatile_functions
515 : * Recursively search for volatile functions within a clause.
516 : *
517 : * Returns true if any volatile function (or operator implemented by a
518 : * volatile function) is found. This test prevents, for example,
519 : * invalid conversions of volatile expressions into indexscan quals.
520 : *
521 : * This will give the right answer only for clauses that have been put
522 : * through expression preprocessing. Callers outside the planner typically
523 : * should use contain_volatile_functions_after_planning() instead, for the
524 : * reasons given there.
525 : *
526 : * We will recursively look into Query nodes (i.e., SubLink sub-selects)
527 : * but not into SubPlans. This is a bit odd, but intentional. If we are
528 : * looking at a SubLink, we are probably deciding whether a query tree
529 : * transformation is safe, and a contained sub-select should affect that;
530 : * for example, duplicating a sub-select containing a volatile function
531 : * would be bad. However, once we've got to the stage of having SubPlans,
532 : * subsequent planning need not consider volatility within those, since
533 : * the executor won't change its evaluation rules for a SubPlan based on
534 : * volatility.
535 : *
536 : * For some node types, for example, RestrictInfo and PathTarget, we cache
537 : * whether we found any volatile functions or not and reuse that value in any
538 : * future checks for that node. All of the logic for determining if the
539 : * cached value should be set to VOLATILITY_NOVOLATILE or VOLATILITY_VOLATILE
540 : * belongs in this function. Any code which makes changes to these nodes
541 : * which could change the outcome this function must set the cached value back
542 : * to VOLATILITY_UNKNOWN. That allows this function to redetermine the
543 : * correct value during the next call, should we need to redetermine if the
544 : * node contains any volatile functions again in the future.
545 : */
546 : bool
547 2000453 : contain_volatile_functions(Node *clause)
548 : {
549 2000453 : return contain_volatile_functions_walker(clause, NULL);
550 : }
551 :
552 : static bool
553 539416 : contain_volatile_functions_checker(Oid func_id, void *context)
554 : {
555 539416 : return (func_volatile(func_id) == PROVOLATILE_VOLATILE);
556 : }
557 :
558 : static bool
559 4532557 : contain_volatile_functions_walker(Node *node, void *context)
560 : {
561 4532557 : if (node == NULL)
562 129510 : return false;
563 : /* Check for volatile functions in node itself */
564 4403047 : if (check_functions_in_node(node, contain_volatile_functions_checker,
565 : context))
566 1143 : return true;
567 :
568 4401904 : if (IsA(node, NextValueExpr))
569 : {
570 : /* NextValueExpr is volatile */
571 21 : return true;
572 : }
573 :
574 4401883 : if (IsA(node, RestrictInfo))
575 : {
576 793724 : RestrictInfo *rinfo = (RestrictInfo *) node;
577 :
578 : /*
579 : * For RestrictInfo, check if we've checked the volatility of it
580 : * before. If so, we can just use the cached value and not bother
581 : * checking it again. Otherwise, check it and cache if whether we
582 : * found any volatile functions.
583 : */
584 793724 : if (rinfo->has_volatile == VOLATILITY_NOVOLATILE)
585 501140 : return false;
586 292584 : else if (rinfo->has_volatile == VOLATILITY_VOLATILE)
587 40 : return true;
588 : else
589 : {
590 : bool hasvolatile;
591 :
592 292544 : hasvolatile = contain_volatile_functions_walker((Node *) rinfo->clause,
593 : context);
594 292544 : if (hasvolatile)
595 68 : rinfo->has_volatile = VOLATILITY_VOLATILE;
596 : else
597 292476 : rinfo->has_volatile = VOLATILITY_NOVOLATILE;
598 :
599 292544 : return hasvolatile;
600 : }
601 : }
602 :
603 3608159 : if (IsA(node, PathTarget))
604 : {
605 234446 : PathTarget *target = (PathTarget *) node;
606 :
607 : /*
608 : * We also do caching for PathTarget the same as we do above for
609 : * RestrictInfos.
610 : */
611 234446 : if (target->has_volatile_expr == VOLATILITY_NOVOLATILE)
612 196180 : return false;
613 38266 : else if (target->has_volatile_expr == VOLATILITY_VOLATILE)
614 0 : return true;
615 : else
616 : {
617 : bool hasvolatile;
618 :
619 38266 : hasvolatile = contain_volatile_functions_walker((Node *) target->exprs,
620 : context);
621 :
622 38266 : if (hasvolatile)
623 0 : target->has_volatile_expr = VOLATILITY_VOLATILE;
624 : else
625 38266 : target->has_volatile_expr = VOLATILITY_NOVOLATILE;
626 :
627 38266 : return hasvolatile;
628 : }
629 : }
630 :
631 : /*
632 : * See notes in contain_mutable_functions_walker about why we treat
633 : * MinMaxExpr, XmlExpr, and CoerceToDomain as immutable, while
634 : * SQLValueFunction is stable. Hence, none of them are of interest here.
635 : */
636 :
637 : /* Recurse to check arguments */
638 3373713 : if (IsA(node, Query))
639 : {
640 : /* Recurse into subselects */
641 4055 : return query_tree_walker((Query *) node,
642 : contain_volatile_functions_walker,
643 : context, 0);
644 : }
645 3369658 : return expression_tree_walker(node, contain_volatile_functions_walker,
646 : context);
647 : }
648 :
649 : /*
650 : * contain_volatile_functions_after_planning
651 : * Test whether given expression contains volatile functions.
652 : *
653 : * This is a wrapper for contain_volatile_functions() that is safe to use from
654 : * outside the planner. The difference is that it first runs the expression
655 : * through expression_planner(). There are two key reasons why we need that:
656 : *
657 : * First, function default arguments will get inserted, which may affect
658 : * volatility (consider "default random()").
659 : *
660 : * Second, inline-able functions will get inlined, which may allow us to
661 : * conclude that the function is really less volatile than it's marked.
662 : * As an example, polymorphic functions must be marked with the most volatile
663 : * behavior that they have for any input type, but once we inline the
664 : * function we may be able to conclude that it's not so volatile for the
665 : * particular input type we're dealing with.
666 : */
667 : bool
668 0 : contain_volatile_functions_after_planning(Expr *expr)
669 : {
670 : /* We assume here that expression_planner() won't scribble on its input */
671 0 : expr = expression_planner(expr);
672 :
673 : /* Now we can search for volatile functions */
674 0 : return contain_volatile_functions((Node *) expr);
675 : }
676 :
677 : /*
678 : * Special purpose version of contain_volatile_functions() for use in COPY:
679 : * ignore nextval(), but treat all other functions normally.
680 : */
681 : bool
682 126 : contain_volatile_functions_not_nextval(Node *clause)
683 : {
684 126 : return contain_volatile_functions_not_nextval_walker(clause, NULL);
685 : }
686 :
687 : static bool
688 32 : contain_volatile_functions_not_nextval_checker(Oid func_id, void *context)
689 : {
690 52 : return (func_id != F_NEXTVAL &&
691 20 : func_volatile(func_id) == PROVOLATILE_VOLATILE);
692 : }
693 :
694 : static bool
695 156 : contain_volatile_functions_not_nextval_walker(Node *node, void *context)
696 : {
697 156 : if (node == NULL)
698 0 : return false;
699 : /* Check for volatile functions in node itself */
700 156 : if (check_functions_in_node(node,
701 : contain_volatile_functions_not_nextval_checker,
702 : context))
703 3 : return true;
704 :
705 : /*
706 : * See notes in contain_mutable_functions_walker about why we treat
707 : * MinMaxExpr, XmlExpr, and CoerceToDomain as immutable, while
708 : * SQLValueFunction is stable. Hence, none of them are of interest here.
709 : * Also, since we're intentionally ignoring nextval(), presumably we
710 : * should ignore NextValueExpr.
711 : */
712 :
713 : /* Recurse to check arguments */
714 153 : if (IsA(node, Query))
715 : {
716 : /* Recurse into subselects */
717 0 : return query_tree_walker((Query *) node,
718 : contain_volatile_functions_not_nextval_walker,
719 : context, 0);
720 : }
721 153 : return expression_tree_walker(node,
722 : contain_volatile_functions_not_nextval_walker,
723 : context);
724 : }
725 :
726 :
727 : /*****************************************************************************
728 : * Check queries for parallel unsafe and/or restricted constructs
729 : *****************************************************************************/
730 :
731 : /*
732 : * max_parallel_hazard
733 : * Find the worst parallel-hazard level in the given query
734 : *
735 : * Returns the worst function hazard property (the earliest in this list:
736 : * PROPARALLEL_UNSAFE, PROPARALLEL_RESTRICTED, PROPARALLEL_SAFE) that can
737 : * be found in the given parsetree. We use this to find out whether the query
738 : * can be parallelized at all. The caller will also save the result in
739 : * PlannerGlobal so as to short-circuit checks of portions of the querytree
740 : * later, in the common case where everything is SAFE.
741 : */
742 : char
743 183279 : max_parallel_hazard(Query *parse)
744 : {
745 : max_parallel_hazard_context context;
746 :
747 183279 : context.max_hazard = PROPARALLEL_SAFE;
748 183279 : context.max_interesting = PROPARALLEL_UNSAFE;
749 183279 : context.safe_param_ids = NIL;
750 183279 : (void) max_parallel_hazard_walker((Node *) parse, &context);
751 183279 : return context.max_hazard;
752 : }
753 :
754 : /*
755 : * is_parallel_safe
756 : * Detect whether the given expr contains only parallel-safe functions
757 : *
758 : * root->glob->maxParallelHazard must previously have been set to the
759 : * result of max_parallel_hazard() on the whole query.
760 : */
761 : bool
762 1329922 : is_parallel_safe(PlannerInfo *root, Node *node)
763 : {
764 : max_parallel_hazard_context context;
765 : PlannerInfo *proot;
766 : ListCell *l;
767 :
768 : /*
769 : * Even if the original querytree contained nothing unsafe, we need to
770 : * search the expression if we have generated any PARAM_EXEC Params while
771 : * planning, because those are parallel-restricted and there might be one
772 : * in this expression. But otherwise we don't need to look.
773 : */
774 1329922 : if (root->glob->maxParallelHazard == PROPARALLEL_SAFE &&
775 791851 : root->glob->paramExecTypes == NIL)
776 769420 : return true;
777 : /* Else use max_parallel_hazard's search logic, but stop on RESTRICTED */
778 560502 : context.max_hazard = PROPARALLEL_SAFE;
779 560502 : context.max_interesting = PROPARALLEL_RESTRICTED;
780 560502 : context.safe_param_ids = NIL;
781 :
782 : /*
783 : * The params that refer to the same or parent query level are considered
784 : * parallel-safe. The idea is that we compute such params at Gather or
785 : * Gather Merge node and pass their value to workers.
786 : */
787 1364348 : for (proot = root; proot != NULL; proot = proot->parent_root)
788 : {
789 847295 : foreach(l, proot->init_plans)
790 : {
791 43449 : SubPlan *initsubplan = (SubPlan *) lfirst(l);
792 :
793 43449 : context.safe_param_ids = list_concat(context.safe_param_ids,
794 43449 : initsubplan->setParam);
795 : }
796 : }
797 :
798 560502 : return !max_parallel_hazard_walker(node, &context);
799 : }
800 :
801 : /* core logic for all parallel-hazard checks */
802 : static bool
803 927443 : max_parallel_hazard_test(char proparallel, max_parallel_hazard_context *context)
804 : {
805 927443 : switch (proparallel)
806 : {
807 774397 : case PROPARALLEL_SAFE:
808 : /* nothing to see here, move along */
809 774397 : break;
810 111779 : case PROPARALLEL_RESTRICTED:
811 : /* increase max_hazard to RESTRICTED */
812 : Assert(context->max_hazard != PROPARALLEL_UNSAFE);
813 111779 : context->max_hazard = proparallel;
814 : /* done if we are not expecting any unsafe functions */
815 111779 : if (context->max_interesting == proparallel)
816 56348 : return true;
817 55431 : break;
818 41267 : case PROPARALLEL_UNSAFE:
819 41267 : context->max_hazard = proparallel;
820 : /* we're always done at the first unsafe construct */
821 41267 : return true;
822 0 : default:
823 0 : elog(ERROR, "unrecognized proparallel value \"%c\"", proparallel);
824 : break;
825 : }
826 829828 : return false;
827 : }
828 :
829 : /* check_functions_in_node callback */
830 : static bool
831 850539 : max_parallel_hazard_checker(Oid func_id, void *context)
832 : {
833 850539 : return max_parallel_hazard_test(func_parallel(func_id),
834 : (max_parallel_hazard_context *) context);
835 : }
836 :
837 : static bool
838 11945615 : max_parallel_hazard_walker(Node *node, max_parallel_hazard_context *context)
839 : {
840 11945615 : if (node == NULL)
841 3067586 : return false;
842 :
843 : /* Check for hazardous functions in node itself */
844 8878029 : if (check_functions_in_node(node, max_parallel_hazard_checker,
845 : context))
846 55632 : return true;
847 :
848 : /*
849 : * It should be OK to treat MinMaxExpr as parallel-safe, since btree
850 : * opclass support functions are generally parallel-safe. XmlExpr is a
851 : * bit more dubious but we can probably get away with it. We err on the
852 : * side of caution by treating CoerceToDomain as parallel-restricted.
853 : * (Note: in principle that's wrong because a domain constraint could
854 : * contain a parallel-unsafe function; but useful constraints probably
855 : * never would have such, and assuming they do would cripple use of
856 : * parallel query in the presence of domain types.) SQLValueFunction
857 : * should be safe in all cases. NextValueExpr is parallel-unsafe.
858 : */
859 8822397 : if (IsA(node, CoerceToDomain))
860 : {
861 9824 : if (max_parallel_hazard_test(PROPARALLEL_RESTRICTED, context))
862 3202 : return true;
863 : }
864 :
865 8812573 : else if (IsA(node, NextValueExpr))
866 : {
867 194 : if (max_parallel_hazard_test(PROPARALLEL_UNSAFE, context))
868 194 : return true;
869 : }
870 :
871 : /*
872 : * Treat window functions as parallel-restricted because we aren't sure
873 : * whether the input row ordering is fully deterministic, and the output
874 : * of window functions might vary across workers if not. (In some cases,
875 : * like where the window frame orders by a primary key, we could relax
876 : * this restriction. But it doesn't currently seem worth expending extra
877 : * effort to do so.)
878 : */
879 8812379 : else if (IsA(node, WindowFunc))
880 : {
881 3092 : if (max_parallel_hazard_test(PROPARALLEL_RESTRICTED, context))
882 1380 : return true;
883 : }
884 :
885 : /*
886 : * As a notational convenience for callers, look through RestrictInfo.
887 : */
888 8809287 : else if (IsA(node, RestrictInfo))
889 : {
890 150134 : RestrictInfo *rinfo = (RestrictInfo *) node;
891 :
892 150134 : return max_parallel_hazard_walker((Node *) rinfo->clause, context);
893 : }
894 :
895 : /*
896 : * Really we should not see SubLink during a max_interesting == restricted
897 : * scan, but if we do, return true.
898 : */
899 8659153 : else if (IsA(node, SubLink))
900 : {
901 24099 : if (max_parallel_hazard_test(PROPARALLEL_RESTRICTED, context))
902 0 : return true;
903 : }
904 :
905 : /*
906 : * Only parallel-safe SubPlans can be sent to workers. Within the
907 : * testexpr of the SubPlan, Params representing the output columns of the
908 : * subplan can be treated as parallel-safe, so temporarily add their IDs
909 : * to the safe_param_ids list while examining the testexpr.
910 : */
911 8635054 : else if (IsA(node, SubPlan))
912 : {
913 16994 : SubPlan *subplan = (SubPlan *) node;
914 : List *save_safe_param_ids;
915 :
916 33823 : if (!subplan->parallel_safe &&
917 16829 : max_parallel_hazard_test(PROPARALLEL_RESTRICTED, context))
918 16829 : return true;
919 165 : save_safe_param_ids = context->safe_param_ids;
920 330 : context->safe_param_ids = list_concat_copy(context->safe_param_ids,
921 165 : subplan->paramIds);
922 165 : if (max_parallel_hazard_walker(subplan->testexpr, context))
923 3 : return true; /* no need to restore safe_param_ids */
924 162 : list_free(context->safe_param_ids);
925 162 : context->safe_param_ids = save_safe_param_ids;
926 : /* we must also check args, but no special Param treatment there */
927 162 : if (max_parallel_hazard_walker((Node *) subplan->args, context))
928 0 : return true;
929 : /* don't want to recurse normally, so we're done */
930 162 : return false;
931 : }
932 :
933 : /*
934 : * We can't pass Params to workers at the moment either, so they are also
935 : * parallel-restricted, unless they are PARAM_EXTERN Params or are
936 : * PARAM_EXEC Params listed in safe_param_ids, meaning they could be
937 : * either generated within workers or can be computed by the leader and
938 : * then their value can be passed to workers.
939 : */
940 8618060 : else if (IsA(node, Param))
941 : {
942 59093 : Param *param = (Param *) node;
943 :
944 59093 : if (param->paramkind == PARAM_EXTERN)
945 30238 : return false;
946 :
947 28855 : if (param->paramkind != PARAM_EXEC ||
948 26334 : !list_member_int(context->safe_param_ids, param->paramid))
949 : {
950 22866 : if (max_parallel_hazard_test(PROPARALLEL_RESTRICTED, context))
951 20378 : return true;
952 : }
953 8477 : return false; /* nothing to recurse to */
954 : }
955 :
956 : /*
957 : * When we're first invoked on a completely unplanned tree, we must
958 : * recurse into subqueries so to as to locate parallel-unsafe constructs
959 : * anywhere in the tree.
960 : */
961 8558967 : else if (IsA(node, Query))
962 : {
963 242619 : Query *query = (Query *) node;
964 :
965 : /* SELECT FOR UPDATE/SHARE must be treated as unsafe */
966 242619 : if (query->rowMarks != NULL)
967 : {
968 3707 : context->max_hazard = PROPARALLEL_UNSAFE;
969 3707 : return true;
970 : }
971 :
972 : /* Recurse into subselects */
973 238912 : return query_tree_walker(query,
974 : max_parallel_hazard_walker,
975 : context, 0);
976 : }
977 :
978 : /* Recurse to check arguments */
979 8348781 : return expression_tree_walker(node,
980 : max_parallel_hazard_walker,
981 : context);
982 : }
983 :
984 :
985 : /*****************************************************************************
986 : * Check clauses for nonstrict functions
987 : *****************************************************************************/
988 :
989 : /*
990 : * contain_nonstrict_functions
991 : * Recursively search for nonstrict functions within a clause.
992 : *
993 : * Returns true if any nonstrict construct is found --- ie, anything that
994 : * could produce non-NULL output with a NULL input.
995 : *
996 : * The idea here is that the caller has verified that the expression contains
997 : * one or more Var or Param nodes (as appropriate for the caller's need), and
998 : * now wishes to prove that the expression result will be NULL if any of these
999 : * inputs is NULL. If we return false, then the proof succeeded.
1000 : */
1001 : bool
1002 1206 : contain_nonstrict_functions(Node *clause)
1003 : {
1004 1206 : return contain_nonstrict_functions_walker(clause, NULL);
1005 : }
1006 :
1007 : static bool
1008 1259 : contain_nonstrict_functions_checker(Oid func_id, void *context)
1009 : {
1010 1259 : return !func_strict(func_id);
1011 : }
1012 :
1013 : static bool
1014 4232 : contain_nonstrict_functions_walker(Node *node, void *context)
1015 : {
1016 4232 : if (node == NULL)
1017 0 : return false;
1018 4232 : if (IsA(node, Aggref))
1019 : {
1020 : /* an aggregate could return non-null with null input */
1021 0 : return true;
1022 : }
1023 4232 : if (IsA(node, GroupingFunc))
1024 : {
1025 : /*
1026 : * A GroupingFunc doesn't evaluate its arguments, and therefore must
1027 : * be treated as nonstrict.
1028 : */
1029 0 : return true;
1030 : }
1031 4232 : if (IsA(node, WindowFunc))
1032 : {
1033 : /* a window function could return non-null with null input */
1034 0 : return true;
1035 : }
1036 4232 : if (IsA(node, SubscriptingRef))
1037 : {
1038 0 : SubscriptingRef *sbsref = (SubscriptingRef *) node;
1039 : const SubscriptRoutines *sbsroutines;
1040 :
1041 : /* Subscripting assignment is always presumed nonstrict */
1042 0 : if (sbsref->refassgnexpr != NULL)
1043 0 : return true;
1044 : /* Otherwise we must look up the subscripting support methods */
1045 0 : sbsroutines = getSubscriptingRoutines(sbsref->refcontainertype, NULL);
1046 0 : if (!(sbsroutines && sbsroutines->fetch_strict))
1047 0 : return true;
1048 : /* else fall through to check args */
1049 : }
1050 4232 : if (IsA(node, DistinctExpr))
1051 : {
1052 : /* IS DISTINCT FROM is inherently non-strict */
1053 0 : return true;
1054 : }
1055 4232 : if (IsA(node, NullIfExpr))
1056 : {
1057 : /* NULLIF is inherently non-strict */
1058 0 : return true;
1059 : }
1060 4232 : if (IsA(node, BoolExpr))
1061 : {
1062 9 : BoolExpr *expr = (BoolExpr *) node;
1063 :
1064 9 : switch (expr->boolop)
1065 : {
1066 9 : case AND_EXPR:
1067 : case OR_EXPR:
1068 : /* AND, OR are inherently non-strict */
1069 9 : return true;
1070 0 : default:
1071 0 : break;
1072 : }
1073 : }
1074 4223 : if (IsA(node, SubLink))
1075 : {
1076 : /* In some cases a sublink might be strict, but in general not */
1077 6 : return true;
1078 : }
1079 4217 : if (IsA(node, SubPlan))
1080 0 : return true;
1081 4217 : if (IsA(node, AlternativeSubPlan))
1082 0 : return true;
1083 4217 : if (IsA(node, FieldStore))
1084 0 : return true;
1085 4217 : if (IsA(node, CoerceViaIO))
1086 : {
1087 : /*
1088 : * CoerceViaIO is strict regardless of whether the I/O functions are,
1089 : * so just go look at its argument; asking check_functions_in_node is
1090 : * useless expense and could deliver the wrong answer.
1091 : */
1092 549 : return contain_nonstrict_functions_walker((Node *) ((CoerceViaIO *) node)->arg,
1093 : context);
1094 : }
1095 3668 : if (IsA(node, ArrayCoerceExpr))
1096 : {
1097 : /*
1098 : * ArrayCoerceExpr is strict at the array level, regardless of what
1099 : * the per-element expression is; so we should ignore elemexpr and
1100 : * recurse only into the arg.
1101 : */
1102 0 : return contain_nonstrict_functions_walker((Node *) ((ArrayCoerceExpr *) node)->arg,
1103 : context);
1104 : }
1105 3668 : if (IsA(node, CaseExpr))
1106 32 : return true;
1107 3636 : if (IsA(node, ArrayExpr))
1108 0 : return true;
1109 3636 : if (IsA(node, RowExpr))
1110 2 : return true;
1111 3634 : if (IsA(node, RowCompareExpr))
1112 0 : return true;
1113 3634 : if (IsA(node, CoalesceExpr))
1114 127 : return true;
1115 3507 : if (IsA(node, MinMaxExpr))
1116 30 : return true;
1117 3477 : if (IsA(node, XmlExpr))
1118 0 : return true;
1119 3477 : if (IsA(node, NullTest))
1120 12 : return true;
1121 3465 : if (IsA(node, BooleanTest))
1122 0 : return true;
1123 3465 : if (IsA(node, JsonConstructorExpr))
1124 6 : return true;
1125 :
1126 : /* Check other function-containing nodes */
1127 3459 : if (check_functions_in_node(node, contain_nonstrict_functions_checker,
1128 : context))
1129 0 : return true;
1130 :
1131 3459 : return expression_tree_walker(node, contain_nonstrict_functions_walker,
1132 : context);
1133 : }
1134 :
1135 : /*****************************************************************************
1136 : * Check clauses for Params
1137 : *****************************************************************************/
1138 :
1139 : /*
1140 : * contain_exec_param
1141 : * Recursively search for PARAM_EXEC Params within a clause.
1142 : *
1143 : * Returns true if the clause contains any PARAM_EXEC Param with a paramid
1144 : * appearing in the given list of Param IDs. Does not descend into
1145 : * subqueries!
1146 : */
1147 : bool
1148 1565 : contain_exec_param(Node *clause, List *param_ids)
1149 : {
1150 1565 : return contain_exec_param_walker(clause, param_ids);
1151 : }
1152 :
1153 : static bool
1154 1709 : contain_exec_param_walker(Node *node, List *param_ids)
1155 : {
1156 1709 : if (node == NULL)
1157 18 : return false;
1158 1691 : if (IsA(node, Param))
1159 : {
1160 6 : Param *p = (Param *) node;
1161 :
1162 12 : if (p->paramkind == PARAM_EXEC &&
1163 6 : list_member_int(param_ids, p->paramid))
1164 6 : return true;
1165 : }
1166 1685 : return expression_tree_walker(node, contain_exec_param_walker, param_ids);
1167 : }
1168 :
1169 : /*****************************************************************************
1170 : * Check clauses for context-dependent nodes
1171 : *****************************************************************************/
1172 :
1173 : /*
1174 : * contain_context_dependent_node
1175 : * Recursively search for context-dependent nodes within a clause.
1176 : *
1177 : * CaseTestExpr nodes must appear directly within the corresponding CaseExpr,
1178 : * not nested within another one, or they'll see the wrong test value. If one
1179 : * appears "bare" in the arguments of a SQL function, then we can't inline the
1180 : * SQL function for fear of creating such a situation. The same applies for
1181 : * CaseTestExpr used within the elemexpr of an ArrayCoerceExpr.
1182 : *
1183 : * CoerceToDomainValue would have the same issue if domain CHECK expressions
1184 : * could get inlined into larger expressions, but presently that's impossible.
1185 : * Still, it might be allowed in future, or other node types with similar
1186 : * issues might get invented. So give this function a generic name, and set
1187 : * up the recursion state to allow multiple flag bits.
1188 : */
1189 : static bool
1190 1648 : contain_context_dependent_node(Node *clause)
1191 : {
1192 1648 : int flags = 0;
1193 :
1194 1648 : return contain_context_dependent_node_walker(clause, &flags);
1195 : }
1196 :
1197 : #define CCDN_CASETESTEXPR_OK 0x0001 /* CaseTestExpr okay here? */
1198 :
1199 : static bool
1200 5051 : contain_context_dependent_node_walker(Node *node, int *flags)
1201 : {
1202 5051 : if (node == NULL)
1203 98 : return false;
1204 4953 : if (IsA(node, CaseTestExpr))
1205 3 : return !(*flags & CCDN_CASETESTEXPR_OK);
1206 4950 : else if (IsA(node, CaseExpr))
1207 : {
1208 0 : CaseExpr *caseexpr = (CaseExpr *) node;
1209 :
1210 : /*
1211 : * If this CASE doesn't have a test expression, then it doesn't create
1212 : * a context in which CaseTestExprs should appear, so just fall
1213 : * through and treat it as a generic expression node.
1214 : */
1215 0 : if (caseexpr->arg)
1216 : {
1217 0 : int save_flags = *flags;
1218 : bool res;
1219 :
1220 : /*
1221 : * Note: in principle, we could distinguish the various sub-parts
1222 : * of a CASE construct and set the flag bit only for some of them,
1223 : * since we are only expecting CaseTestExprs to appear in the
1224 : * "expr" subtree of the CaseWhen nodes. But it doesn't really
1225 : * seem worth any extra code. If there are any bare CaseTestExprs
1226 : * elsewhere in the CASE, something's wrong already.
1227 : */
1228 0 : *flags |= CCDN_CASETESTEXPR_OK;
1229 0 : res = expression_tree_walker(node,
1230 : contain_context_dependent_node_walker,
1231 : flags);
1232 0 : *flags = save_flags;
1233 0 : return res;
1234 : }
1235 : }
1236 4950 : else if (IsA(node, ArrayCoerceExpr))
1237 : {
1238 0 : ArrayCoerceExpr *ac = (ArrayCoerceExpr *) node;
1239 : int save_flags;
1240 : bool res;
1241 :
1242 : /* Check the array expression */
1243 0 : if (contain_context_dependent_node_walker((Node *) ac->arg, flags))
1244 0 : return true;
1245 :
1246 : /* Check the elemexpr, which is allowed to contain CaseTestExpr */
1247 0 : save_flags = *flags;
1248 0 : *flags |= CCDN_CASETESTEXPR_OK;
1249 0 : res = contain_context_dependent_node_walker((Node *) ac->elemexpr,
1250 : flags);
1251 0 : *flags = save_flags;
1252 0 : return res;
1253 : }
1254 4950 : return expression_tree_walker(node, contain_context_dependent_node_walker,
1255 : flags);
1256 : }
1257 :
1258 : /*****************************************************************************
1259 : * Check clauses for Vars passed to non-leakproof functions
1260 : *****************************************************************************/
1261 :
1262 : /*
1263 : * contain_leaked_vars
1264 : * Recursively scan a clause to discover whether it contains any Var
1265 : * nodes (of the current query level) that are passed as arguments to
1266 : * leaky functions.
1267 : *
1268 : * Returns true if the clause contains any non-leakproof functions that are
1269 : * passed Var nodes of the current query level, and which might therefore leak
1270 : * data. Such clauses must be applied after any lower-level security barrier
1271 : * clauses.
1272 : */
1273 : bool
1274 4149 : contain_leaked_vars(Node *clause)
1275 : {
1276 4149 : return contain_leaked_vars_walker(clause, NULL);
1277 : }
1278 :
1279 : static bool
1280 4093 : contain_leaked_vars_checker(Oid func_id, void *context)
1281 : {
1282 4093 : return !get_func_leakproof(func_id);
1283 : }
1284 :
1285 : static bool
1286 9680 : contain_leaked_vars_walker(Node *node, void *context)
1287 : {
1288 9680 : if (node == NULL)
1289 0 : return false;
1290 :
1291 9680 : switch (nodeTag(node))
1292 : {
1293 5551 : case T_Var:
1294 : case T_Const:
1295 : case T_Param:
1296 : case T_ArrayExpr:
1297 : case T_FieldSelect:
1298 : case T_FieldStore:
1299 : case T_NamedArgExpr:
1300 : case T_BoolExpr:
1301 : case T_RelabelType:
1302 : case T_CollateExpr:
1303 : case T_CaseExpr:
1304 : case T_CaseTestExpr:
1305 : case T_RowExpr:
1306 : case T_SQLValueFunction:
1307 : case T_NullTest:
1308 : case T_BooleanTest:
1309 : case T_NextValueExpr:
1310 : case T_ReturningExpr:
1311 : case T_List:
1312 :
1313 : /*
1314 : * We know these node types don't contain function calls; but
1315 : * something further down in the node tree might.
1316 : */
1317 5551 : break;
1318 :
1319 4093 : case T_FuncExpr:
1320 : case T_OpExpr:
1321 : case T_DistinctExpr:
1322 : case T_NullIfExpr:
1323 : case T_ScalarArrayOpExpr:
1324 : case T_CoerceViaIO:
1325 : case T_ArrayCoerceExpr:
1326 :
1327 : /*
1328 : * If node contains a leaky function call, and there's any Var
1329 : * underneath it, reject.
1330 : */
1331 4093 : if (check_functions_in_node(node, contain_leaked_vars_checker,
1332 1351 : context) &&
1333 1351 : contain_var_clause(node))
1334 1323 : return true;
1335 2770 : break;
1336 :
1337 0 : case T_SubscriptingRef:
1338 : {
1339 0 : SubscriptingRef *sbsref = (SubscriptingRef *) node;
1340 : const SubscriptRoutines *sbsroutines;
1341 :
1342 : /* Consult the subscripting support method info */
1343 0 : sbsroutines = getSubscriptingRoutines(sbsref->refcontainertype,
1344 : NULL);
1345 0 : if (!sbsroutines ||
1346 0 : !(sbsref->refassgnexpr != NULL ?
1347 0 : sbsroutines->store_leakproof :
1348 0 : sbsroutines->fetch_leakproof))
1349 : {
1350 : /* Node is leaky, so reject if it contains Vars */
1351 0 : if (contain_var_clause(node))
1352 0 : return true;
1353 : }
1354 : }
1355 0 : break;
1356 :
1357 0 : case T_RowCompareExpr:
1358 : {
1359 : /*
1360 : * It's worth special-casing this because a leaky comparison
1361 : * function only compromises one pair of row elements, which
1362 : * might not contain Vars while others do.
1363 : */
1364 0 : RowCompareExpr *rcexpr = (RowCompareExpr *) node;
1365 : ListCell *opid;
1366 : ListCell *larg;
1367 : ListCell *rarg;
1368 :
1369 0 : forthree(opid, rcexpr->opnos,
1370 : larg, rcexpr->largs,
1371 : rarg, rcexpr->rargs)
1372 : {
1373 0 : Oid funcid = get_opcode(lfirst_oid(opid));
1374 :
1375 0 : if (!get_func_leakproof(funcid) &&
1376 0 : (contain_var_clause((Node *) lfirst(larg)) ||
1377 0 : contain_var_clause((Node *) lfirst(rarg))))
1378 0 : return true;
1379 : }
1380 : }
1381 0 : break;
1382 :
1383 0 : case T_MinMaxExpr:
1384 : {
1385 : /*
1386 : * MinMaxExpr is leakproof if the comparison function it calls
1387 : * is leakproof.
1388 : */
1389 0 : MinMaxExpr *minmaxexpr = (MinMaxExpr *) node;
1390 : TypeCacheEntry *typentry;
1391 : bool leakproof;
1392 :
1393 : /* Look up the btree comparison function for the datatype */
1394 0 : typentry = lookup_type_cache(minmaxexpr->minmaxtype,
1395 : TYPECACHE_CMP_PROC);
1396 0 : if (OidIsValid(typentry->cmp_proc))
1397 0 : leakproof = get_func_leakproof(typentry->cmp_proc);
1398 : else
1399 : {
1400 : /*
1401 : * The executor will throw an error, but here we just
1402 : * treat the missing function as leaky.
1403 : */
1404 0 : leakproof = false;
1405 : }
1406 :
1407 0 : if (!leakproof &&
1408 0 : contain_var_clause((Node *) minmaxexpr->args))
1409 0 : return true;
1410 : }
1411 0 : break;
1412 :
1413 21 : case T_CurrentOfExpr:
1414 :
1415 : /*
1416 : * WHERE CURRENT OF doesn't contain leaky function calls.
1417 : * Moreover, it is essential that this is considered non-leaky,
1418 : * since the planner must always generate a TID scan when CURRENT
1419 : * OF is present -- cf. cost_tidscan.
1420 : */
1421 21 : return false;
1422 :
1423 15 : default:
1424 :
1425 : /*
1426 : * If we don't recognize the node tag, assume it might be leaky.
1427 : * This prevents an unexpected security hole if someone adds a new
1428 : * node type that can call a function.
1429 : */
1430 15 : return true;
1431 : }
1432 8321 : return expression_tree_walker(node, contain_leaked_vars_walker,
1433 : context);
1434 : }
1435 :
1436 : /*
1437 : * find_nonnullable_rels
1438 : * Determine which base rels are forced nonnullable by given clause.
1439 : *
1440 : * Returns the set of all Relids that are referenced in the clause in such
1441 : * a way that the clause cannot possibly return TRUE if any of these Relids
1442 : * is an all-NULL row. (It is OK to err on the side of conservatism; hence
1443 : * the analysis here is simplistic.)
1444 : *
1445 : * The semantics here are subtly different from contain_nonstrict_functions:
1446 : * that function is concerned with NULL results from arbitrary expressions,
1447 : * but here we assume that the input is a Boolean expression, and wish to
1448 : * see if NULL inputs will provably cause a FALSE-or-NULL result. We expect
1449 : * the expression to have been AND/OR flattened and converted to implicit-AND
1450 : * format.
1451 : *
1452 : * Note: this function is largely duplicative of find_nonnullable_vars().
1453 : * The reason not to simplify this function into a thin wrapper around
1454 : * find_nonnullable_vars() is that the tested conditions really are different:
1455 : * a clause like "t1.v1 IS NOT NULL OR t1.v2 IS NOT NULL" does not prove
1456 : * that either v1 or v2 can't be NULL, but it does prove that the t1 row
1457 : * as a whole can't be all-NULL. Also, the behavior for PHVs is different.
1458 : *
1459 : * top_level is true while scanning top-level AND/OR structure; here, showing
1460 : * the result is either FALSE or NULL is good enough. top_level is false when
1461 : * we have descended below a NOT or a strict function: now we must be able to
1462 : * prove that the subexpression goes to NULL.
1463 : *
1464 : * We don't use expression_tree_walker here because we don't want to descend
1465 : * through very many kinds of nodes; only the ones we can be sure are strict.
1466 : */
1467 : Relids
1468 58730 : find_nonnullable_rels(Node *clause)
1469 : {
1470 58730 : return find_nonnullable_rels_walker(clause, true);
1471 : }
1472 :
1473 : static Relids
1474 397314 : find_nonnullable_rels_walker(Node *node, bool top_level)
1475 : {
1476 397314 : Relids result = NULL;
1477 : ListCell *l;
1478 :
1479 397314 : if (node == NULL)
1480 3473 : return NULL;
1481 393841 : if (IsA(node, Var))
1482 : {
1483 126644 : Var *var = (Var *) node;
1484 :
1485 126644 : if (var->varlevelsup == 0)
1486 126644 : result = bms_make_singleton(var->varno);
1487 : }
1488 267197 : else if (IsA(node, List))
1489 : {
1490 : /*
1491 : * At top level, we are examining an implicit-AND list: if any of the
1492 : * arms produces FALSE-or-NULL then the result is FALSE-or-NULL. If
1493 : * not at top level, we are examining the arguments of a strict
1494 : * function: if any of them produce NULL then the result of the
1495 : * function must be NULL. So in both cases, the set of nonnullable
1496 : * rels is the union of those found in the arms, and we pass down the
1497 : * top_level flag unmodified.
1498 : */
1499 383090 : foreach(l, (List *) node)
1500 : {
1501 244208 : result = bms_join(result,
1502 244208 : find_nonnullable_rels_walker(lfirst(l),
1503 : top_level));
1504 : }
1505 : }
1506 128315 : else if (IsA(node, FuncExpr))
1507 : {
1508 4537 : FuncExpr *expr = (FuncExpr *) node;
1509 :
1510 4537 : if (func_strict(expr->funcid))
1511 4441 : result = find_nonnullable_rels_walker((Node *) expr->args, false);
1512 : }
1513 123778 : else if (IsA(node, OpExpr))
1514 : {
1515 71536 : OpExpr *expr = (OpExpr *) node;
1516 :
1517 71536 : set_opfuncid(expr);
1518 71536 : if (func_strict(expr->opfuncid))
1519 71536 : result = find_nonnullable_rels_walker((Node *) expr->args, false);
1520 : }
1521 52242 : else if (IsA(node, ScalarArrayOpExpr))
1522 : {
1523 4739 : ScalarArrayOpExpr *expr = (ScalarArrayOpExpr *) node;
1524 :
1525 4739 : if (is_strict_saop(expr, true))
1526 4739 : result = find_nonnullable_rels_walker((Node *) expr->args, false);
1527 : }
1528 47503 : else if (IsA(node, BoolExpr))
1529 : {
1530 5885 : BoolExpr *expr = (BoolExpr *) node;
1531 :
1532 5885 : switch (expr->boolop)
1533 : {
1534 297 : case AND_EXPR:
1535 : /* At top level we can just recurse (to the List case) */
1536 297 : if (top_level)
1537 : {
1538 297 : result = find_nonnullable_rels_walker((Node *) expr->args,
1539 : top_level);
1540 297 : break;
1541 : }
1542 :
1543 : /*
1544 : * Below top level, even if one arm produces NULL, the result
1545 : * could be FALSE (hence not NULL). However, if *all* the
1546 : * arms produce NULL then the result is NULL, so we can take
1547 : * the intersection of the sets of nonnullable rels, just as
1548 : * for OR. Fall through to share code.
1549 : */
1550 : pg_fallthrough;
1551 : case OR_EXPR:
1552 :
1553 : /*
1554 : * OR is strict if all of its arms are, so we can take the
1555 : * intersection of the sets of nonnullable rels for each arm.
1556 : * This works for both values of top_level.
1557 : */
1558 7246 : foreach(l, expr->args)
1559 : {
1560 : Relids subresult;
1561 :
1562 5919 : subresult = find_nonnullable_rels_walker(lfirst(l),
1563 : top_level);
1564 5919 : if (result == NULL) /* first subresult? */
1565 2976 : result = subresult;
1566 : else
1567 2943 : result = bms_int_members(result, subresult);
1568 :
1569 : /*
1570 : * If the intersection is empty, we can stop looking. This
1571 : * also justifies the test for first-subresult above.
1572 : */
1573 5919 : if (bms_is_empty(result))
1574 1649 : break;
1575 : }
1576 2976 : break;
1577 2612 : case NOT_EXPR:
1578 : /* NOT will return null if its arg is null */
1579 2612 : result = find_nonnullable_rels_walker((Node *) expr->args,
1580 : false);
1581 2612 : break;
1582 0 : default:
1583 0 : elog(ERROR, "unrecognized boolop: %d", (int) expr->boolop);
1584 : break;
1585 : }
1586 : }
1587 41618 : else if (IsA(node, RelabelType))
1588 : {
1589 2155 : RelabelType *expr = (RelabelType *) node;
1590 :
1591 2155 : result = find_nonnullable_rels_walker((Node *) expr->arg, top_level);
1592 : }
1593 39463 : else if (IsA(node, CoerceViaIO))
1594 : {
1595 : /* not clear this is useful, but it can't hurt */
1596 104 : CoerceViaIO *expr = (CoerceViaIO *) node;
1597 :
1598 104 : result = find_nonnullable_rels_walker((Node *) expr->arg, top_level);
1599 : }
1600 39359 : else if (IsA(node, ArrayCoerceExpr))
1601 : {
1602 : /* ArrayCoerceExpr is strict at the array level; ignore elemexpr */
1603 0 : ArrayCoerceExpr *expr = (ArrayCoerceExpr *) node;
1604 :
1605 0 : result = find_nonnullable_rels_walker((Node *) expr->arg, top_level);
1606 : }
1607 39359 : else if (IsA(node, ConvertRowtypeExpr))
1608 : {
1609 : /* not clear this is useful, but it can't hurt */
1610 0 : ConvertRowtypeExpr *expr = (ConvertRowtypeExpr *) node;
1611 :
1612 0 : result = find_nonnullable_rels_walker((Node *) expr->arg, top_level);
1613 : }
1614 39359 : else if (IsA(node, CollateExpr))
1615 : {
1616 0 : CollateExpr *expr = (CollateExpr *) node;
1617 :
1618 0 : result = find_nonnullable_rels_walker((Node *) expr->arg, top_level);
1619 : }
1620 39359 : else if (IsA(node, NullTest))
1621 : {
1622 : /* IS NOT NULL can be considered strict, but only at top level */
1623 3133 : NullTest *expr = (NullTest *) node;
1624 :
1625 3133 : if (top_level && expr->nulltesttype == IS_NOT_NULL && !expr->argisrow)
1626 2178 : result = find_nonnullable_rels_walker((Node *) expr->arg, false);
1627 : }
1628 36226 : else if (IsA(node, BooleanTest))
1629 : {
1630 : /* Boolean tests that reject NULL are strict at top level */
1631 103 : BooleanTest *expr = (BooleanTest *) node;
1632 :
1633 103 : if (top_level &&
1634 103 : (expr->booltesttype == IS_TRUE ||
1635 103 : expr->booltesttype == IS_FALSE ||
1636 3 : expr->booltesttype == IS_NOT_UNKNOWN))
1637 100 : result = find_nonnullable_rels_walker((Node *) expr->arg, false);
1638 : }
1639 36123 : else if (IsA(node, SubPlan))
1640 : {
1641 63 : SubPlan *splan = (SubPlan *) node;
1642 :
1643 : /*
1644 : * For some types of SubPlan, we can infer strictness from Vars in the
1645 : * testexpr (the LHS of the original SubLink).
1646 : *
1647 : * For ANY_SUBLINK, if the subquery produces zero rows, the result is
1648 : * always FALSE. If the subquery produces more than one row, the
1649 : * per-row results of the testexpr are combined using OR semantics.
1650 : * Hence ANY_SUBLINK can be strict only at top level, but there it's
1651 : * as strict as the testexpr is.
1652 : *
1653 : * For ROWCOMPARE_SUBLINK, if the subquery produces zero rows, the
1654 : * result is always NULL. Otherwise, the result is as strict as the
1655 : * testexpr is. So we can check regardless of top_level.
1656 : *
1657 : * We can't prove anything for other sublink types (in particular,
1658 : * note that ALL_SUBLINK will return TRUE if the subquery is empty).
1659 : */
1660 63 : if ((top_level && splan->subLinkType == ANY_SUBLINK) ||
1661 42 : splan->subLinkType == ROWCOMPARE_SUBLINK)
1662 21 : result = find_nonnullable_rels_walker(splan->testexpr, top_level);
1663 : }
1664 36060 : else if (IsA(node, PlaceHolderVar))
1665 : {
1666 274 : PlaceHolderVar *phv = (PlaceHolderVar *) node;
1667 :
1668 : /*
1669 : * If the contained expression forces any rels non-nullable, so does
1670 : * the PHV.
1671 : */
1672 274 : result = find_nonnullable_rels_walker((Node *) phv->phexpr, top_level);
1673 :
1674 : /*
1675 : * If the PHV's syntactic scope is exactly one rel, it will be forced
1676 : * to be evaluated at that rel, and so it will behave like a Var of
1677 : * that rel: if the rel's entire output goes to null, so will the PHV.
1678 : * (If the syntactic scope is a join, we know that the PHV will go to
1679 : * null if the whole join does; but that is AND semantics while we
1680 : * need OR semantics for find_nonnullable_rels' result, so we can't do
1681 : * anything with the knowledge.)
1682 : */
1683 548 : if (phv->phlevelsup == 0 &&
1684 274 : bms_membership(phv->phrels) == BMS_SINGLETON)
1685 178 : result = bms_add_members(result, phv->phrels);
1686 : }
1687 393841 : return result;
1688 : }
1689 :
1690 : /*
1691 : * find_nonnullable_vars
1692 : * Determine which Vars are forced nonnullable by given clause.
1693 : *
1694 : * Returns the set of all level-zero Vars that are referenced in the clause in
1695 : * such a way that the clause cannot possibly return TRUE if any of these Vars
1696 : * is NULL. (It is OK to err on the side of conservatism; hence the analysis
1697 : * here is simplistic.)
1698 : *
1699 : * The semantics here are subtly different from contain_nonstrict_functions:
1700 : * that function is concerned with NULL results from arbitrary expressions,
1701 : * but here we assume that the input is a Boolean expression, and wish to
1702 : * see if NULL inputs will provably cause a FALSE-or-NULL result. We expect
1703 : * the expression to have been AND/OR flattened and converted to implicit-AND
1704 : * format.
1705 : *
1706 : * Attnos of the identified Vars are returned in a multibitmapset (a List of
1707 : * Bitmapsets). List indexes correspond to relids (varnos), while the per-rel
1708 : * Bitmapsets hold varattnos offset by FirstLowInvalidHeapAttributeNumber.
1709 : *
1710 : * top_level is true while scanning top-level AND/OR structure; here, showing
1711 : * the result is either FALSE or NULL is good enough. top_level is false when
1712 : * we have descended below a NOT or a strict function: now we must be able to
1713 : * prove that the subexpression goes to NULL.
1714 : *
1715 : * We don't use expression_tree_walker here because we don't want to descend
1716 : * through very many kinds of nodes; only the ones we can be sure are strict.
1717 : */
1718 : List *
1719 690 : find_nonnullable_vars(Node *clause)
1720 : {
1721 690 : return find_nonnullable_vars_walker(clause, true);
1722 : }
1723 :
1724 : static List *
1725 4879 : find_nonnullable_vars_walker(Node *node, bool top_level)
1726 : {
1727 4879 : List *result = NIL;
1728 : ListCell *l;
1729 :
1730 4879 : if (node == NULL)
1731 3 : return NIL;
1732 4876 : if (IsA(node, Var))
1733 : {
1734 1897 : Var *var = (Var *) node;
1735 :
1736 1897 : if (var->varlevelsup == 0)
1737 1897 : result = mbms_add_member(result,
1738 : var->varno,
1739 1897 : var->varattno - FirstLowInvalidHeapAttributeNumber);
1740 : }
1741 2979 : else if (IsA(node, List))
1742 : {
1743 : /*
1744 : * At top level, we are examining an implicit-AND list: if any of the
1745 : * arms produces FALSE-or-NULL then the result is FALSE-or-NULL. If
1746 : * not at top level, we are examining the arguments of a strict
1747 : * function: if any of them produce NULL then the result of the
1748 : * function must be NULL. So in both cases, the set of nonnullable
1749 : * vars is the union of those found in the arms, and we pass down the
1750 : * top_level flag unmodified.
1751 : */
1752 4657 : foreach(l, (List *) node)
1753 : {
1754 2964 : result = mbms_add_members(result,
1755 2964 : find_nonnullable_vars_walker(lfirst(l),
1756 : top_level));
1757 : }
1758 : }
1759 1286 : else if (IsA(node, FuncExpr))
1760 : {
1761 6 : FuncExpr *expr = (FuncExpr *) node;
1762 :
1763 6 : if (func_strict(expr->funcid))
1764 6 : result = find_nonnullable_vars_walker((Node *) expr->args, false);
1765 : }
1766 1280 : else if (IsA(node, OpExpr))
1767 : {
1768 980 : OpExpr *expr = (OpExpr *) node;
1769 :
1770 980 : set_opfuncid(expr);
1771 980 : if (func_strict(expr->opfuncid))
1772 980 : result = find_nonnullable_vars_walker((Node *) expr->args, false);
1773 : }
1774 300 : else if (IsA(node, ScalarArrayOpExpr))
1775 : {
1776 0 : ScalarArrayOpExpr *expr = (ScalarArrayOpExpr *) node;
1777 :
1778 0 : if (is_strict_saop(expr, true))
1779 0 : result = find_nonnullable_vars_walker((Node *) expr->args, false);
1780 : }
1781 300 : else if (IsA(node, BoolExpr))
1782 : {
1783 98 : BoolExpr *expr = (BoolExpr *) node;
1784 :
1785 98 : switch (expr->boolop)
1786 : {
1787 0 : case AND_EXPR:
1788 :
1789 : /*
1790 : * At top level we can just recurse (to the List case), since
1791 : * the result should be the union of what we can prove in each
1792 : * arm.
1793 : */
1794 0 : if (top_level)
1795 : {
1796 0 : result = find_nonnullable_vars_walker((Node *) expr->args,
1797 : top_level);
1798 0 : break;
1799 : }
1800 :
1801 : /*
1802 : * Below top level, even if one arm produces NULL, the result
1803 : * could be FALSE (hence not NULL). However, if *all* the
1804 : * arms produce NULL then the result is NULL, so we can take
1805 : * the intersection of the sets of nonnullable vars, just as
1806 : * for OR. Fall through to share code.
1807 : */
1808 : pg_fallthrough;
1809 : case OR_EXPR:
1810 :
1811 : /*
1812 : * OR is strict if all of its arms are, so we can take the
1813 : * intersection of the sets of nonnullable vars for each arm.
1814 : * This works for both values of top_level.
1815 : */
1816 176 : foreach(l, expr->args)
1817 : {
1818 : List *subresult;
1819 :
1820 176 : subresult = find_nonnullable_vars_walker(lfirst(l),
1821 : top_level);
1822 176 : if (result == NIL) /* first subresult? */
1823 78 : result = subresult;
1824 : else
1825 98 : result = mbms_int_members(result, subresult);
1826 :
1827 : /*
1828 : * If the intersection is empty, we can stop looking. This
1829 : * also justifies the test for first-subresult above.
1830 : */
1831 176 : if (result == NIL)
1832 78 : break;
1833 : }
1834 78 : break;
1835 20 : case NOT_EXPR:
1836 : /* NOT will return null if its arg is null */
1837 20 : result = find_nonnullable_vars_walker((Node *) expr->args,
1838 : false);
1839 20 : break;
1840 0 : default:
1841 0 : elog(ERROR, "unrecognized boolop: %d", (int) expr->boolop);
1842 : break;
1843 : }
1844 : }
1845 202 : else if (IsA(node, RelabelType))
1846 : {
1847 28 : RelabelType *expr = (RelabelType *) node;
1848 :
1849 28 : result = find_nonnullable_vars_walker((Node *) expr->arg, top_level);
1850 : }
1851 174 : else if (IsA(node, CoerceViaIO))
1852 : {
1853 : /* not clear this is useful, but it can't hurt */
1854 15 : CoerceViaIO *expr = (CoerceViaIO *) node;
1855 :
1856 15 : result = find_nonnullable_vars_walker((Node *) expr->arg, false);
1857 : }
1858 159 : else if (IsA(node, ArrayCoerceExpr))
1859 : {
1860 : /* ArrayCoerceExpr is strict at the array level; ignore elemexpr */
1861 0 : ArrayCoerceExpr *expr = (ArrayCoerceExpr *) node;
1862 :
1863 0 : result = find_nonnullable_vars_walker((Node *) expr->arg, top_level);
1864 : }
1865 159 : else if (IsA(node, ConvertRowtypeExpr))
1866 : {
1867 : /* not clear this is useful, but it can't hurt */
1868 0 : ConvertRowtypeExpr *expr = (ConvertRowtypeExpr *) node;
1869 :
1870 0 : result = find_nonnullable_vars_walker((Node *) expr->arg, top_level);
1871 : }
1872 159 : else if (IsA(node, CollateExpr))
1873 : {
1874 0 : CollateExpr *expr = (CollateExpr *) node;
1875 :
1876 0 : result = find_nonnullable_vars_walker((Node *) expr->arg, top_level);
1877 : }
1878 159 : else if (IsA(node, NullTest))
1879 : {
1880 : /* IS NOT NULL can be considered strict, but only at top level */
1881 78 : NullTest *expr = (NullTest *) node;
1882 :
1883 78 : if (top_level && expr->nulltesttype == IS_NOT_NULL && !expr->argisrow)
1884 0 : result = find_nonnullable_vars_walker((Node *) expr->arg, false);
1885 : }
1886 81 : else if (IsA(node, BooleanTest))
1887 : {
1888 : /* Boolean tests that reject NULL are strict at top level */
1889 0 : BooleanTest *expr = (BooleanTest *) node;
1890 :
1891 0 : if (top_level &&
1892 0 : (expr->booltesttype == IS_TRUE ||
1893 0 : expr->booltesttype == IS_FALSE ||
1894 0 : expr->booltesttype == IS_NOT_UNKNOWN))
1895 0 : result = find_nonnullable_vars_walker((Node *) expr->arg, false);
1896 : }
1897 81 : else if (IsA(node, SubPlan))
1898 : {
1899 0 : SubPlan *splan = (SubPlan *) node;
1900 :
1901 : /* See analysis in find_nonnullable_rels_walker */
1902 0 : if ((top_level && splan->subLinkType == ANY_SUBLINK) ||
1903 0 : splan->subLinkType == ROWCOMPARE_SUBLINK)
1904 0 : result = find_nonnullable_vars_walker(splan->testexpr, top_level);
1905 : }
1906 81 : else if (IsA(node, PlaceHolderVar))
1907 : {
1908 0 : PlaceHolderVar *phv = (PlaceHolderVar *) node;
1909 :
1910 0 : result = find_nonnullable_vars_walker((Node *) phv->phexpr, top_level);
1911 : }
1912 4876 : return result;
1913 : }
1914 :
1915 : /*
1916 : * find_forced_null_vars
1917 : * Determine which Vars must be NULL for the given clause to return TRUE.
1918 : *
1919 : * This is the complement of find_nonnullable_vars: find the level-zero Vars
1920 : * that must be NULL for the clause to return TRUE. (It is OK to err on the
1921 : * side of conservatism; hence the analysis here is simplistic. In fact,
1922 : * we only detect simple "var IS NULL" tests at the top level.)
1923 : *
1924 : * As with find_nonnullable_vars, we return the varattnos of the identified
1925 : * Vars in a multibitmapset.
1926 : */
1927 : List *
1928 68915 : find_forced_null_vars(Node *node)
1929 : {
1930 68915 : List *result = NIL;
1931 : Var *var;
1932 : ListCell *l;
1933 :
1934 68915 : if (node == NULL)
1935 3006 : return NIL;
1936 : /* Check single-clause cases using subroutine */
1937 65909 : var = find_forced_null_var(node);
1938 65909 : if (var)
1939 : {
1940 730 : result = mbms_add_member(result,
1941 : var->varno,
1942 730 : var->varattno - FirstLowInvalidHeapAttributeNumber);
1943 : }
1944 : /* Otherwise, handle AND-conditions */
1945 65179 : else if (IsA(node, List))
1946 : {
1947 : /*
1948 : * At top level, we are examining an implicit-AND list: if any of the
1949 : * arms produces FALSE-or-NULL then the result is FALSE-or-NULL.
1950 : */
1951 65909 : foreach(l, (List *) node)
1952 : {
1953 40545 : result = mbms_add_members(result,
1954 40545 : find_forced_null_vars((Node *) lfirst(l)));
1955 : }
1956 : }
1957 39815 : else if (IsA(node, BoolExpr))
1958 : {
1959 3592 : BoolExpr *expr = (BoolExpr *) node;
1960 :
1961 : /*
1962 : * We don't bother considering the OR case, because it's fairly
1963 : * unlikely anyone would write "v1 IS NULL OR v1 IS NULL". Likewise,
1964 : * the NOT case isn't worth expending code on.
1965 : */
1966 3592 : if (expr->boolop == AND_EXPR)
1967 : {
1968 : /* At top level we can just recurse (to the List case) */
1969 0 : result = find_forced_null_vars((Node *) expr->args);
1970 : }
1971 : }
1972 65909 : return result;
1973 : }
1974 :
1975 : /*
1976 : * find_forced_null_var
1977 : * Return the Var forced null by the given clause, or NULL if it's
1978 : * not an IS NULL-type clause. For success, the clause must enforce
1979 : * *only* nullness of the particular Var, not any other conditions.
1980 : *
1981 : * This is just the single-clause case of find_forced_null_vars(), without
1982 : * any allowance for AND conditions. It's used by initsplan.c on individual
1983 : * qual clauses. The reason for not just applying find_forced_null_vars()
1984 : * is that if an AND of an IS NULL clause with something else were to somehow
1985 : * survive AND/OR flattening, initsplan.c might get fooled into discarding
1986 : * the whole clause when only the IS NULL part of it had been proved redundant.
1987 : */
1988 : Var *
1989 342688 : find_forced_null_var(Node *node)
1990 : {
1991 342688 : if (node == NULL)
1992 0 : return NULL;
1993 342688 : if (IsA(node, NullTest))
1994 : {
1995 : /* check for var IS NULL */
1996 6448 : NullTest *expr = (NullTest *) node;
1997 :
1998 6448 : if (expr->nulltesttype == IS_NULL && !expr->argisrow)
1999 : {
2000 2213 : Var *var = (Var *) expr->arg;
2001 :
2002 2213 : if (var && IsA(var, Var) &&
2003 2135 : var->varlevelsup == 0)
2004 2135 : return var;
2005 : }
2006 : }
2007 336240 : else if (IsA(node, BooleanTest))
2008 : {
2009 : /* var IS UNKNOWN is equivalent to var IS NULL */
2010 412 : BooleanTest *expr = (BooleanTest *) node;
2011 :
2012 412 : if (expr->booltesttype == IS_UNKNOWN)
2013 : {
2014 27 : Var *var = (Var *) expr->arg;
2015 :
2016 27 : if (var && IsA(var, Var) &&
2017 27 : var->varlevelsup == 0)
2018 27 : return var;
2019 : }
2020 : }
2021 340526 : return NULL;
2022 : }
2023 :
2024 : /*
2025 : * Can we treat a ScalarArrayOpExpr as strict?
2026 : *
2027 : * If "falseOK" is true, then a "false" result can be considered strict,
2028 : * else we need to guarantee an actual NULL result for NULL input.
2029 : *
2030 : * "foo op ALL array" is strict if the op is strict *and* we can prove
2031 : * that the array input isn't an empty array. We can check that
2032 : * for the cases of an array constant and an ARRAY[] construct.
2033 : *
2034 : * "foo op ANY array" is strict in the falseOK sense if the op is strict.
2035 : * If not falseOK, the test is the same as for "foo op ALL array".
2036 : */
2037 : static bool
2038 4739 : is_strict_saop(ScalarArrayOpExpr *expr, bool falseOK)
2039 : {
2040 : Node *rightop;
2041 :
2042 : /* The contained operator must be strict. */
2043 4739 : set_sa_opfuncid(expr);
2044 4739 : if (!func_strict(expr->opfuncid))
2045 0 : return false;
2046 : /* If ANY and falseOK, that's all we need to check. */
2047 4739 : if (expr->useOr && falseOK)
2048 4657 : return true;
2049 : /* Else, we have to see if the array is provably non-empty. */
2050 : Assert(list_length(expr->args) == 2);
2051 82 : rightop = (Node *) lsecond(expr->args);
2052 82 : if (rightop && IsA(rightop, Const))
2053 0 : {
2054 82 : Datum arraydatum = ((Const *) rightop)->constvalue;
2055 82 : bool arrayisnull = ((Const *) rightop)->constisnull;
2056 : ArrayType *arrayval;
2057 : int nitems;
2058 :
2059 82 : if (arrayisnull)
2060 0 : return false;
2061 82 : arrayval = DatumGetArrayTypeP(arraydatum);
2062 82 : nitems = ArrayGetNItems(ARR_NDIM(arrayval), ARR_DIMS(arrayval));
2063 82 : if (nitems > 0)
2064 82 : return true;
2065 : }
2066 0 : else if (rightop && IsA(rightop, ArrayExpr))
2067 : {
2068 0 : ArrayExpr *arrayexpr = (ArrayExpr *) rightop;
2069 :
2070 0 : if (arrayexpr->elements != NIL && !arrayexpr->multidims)
2071 0 : return true;
2072 : }
2073 0 : return false;
2074 : }
2075 :
2076 :
2077 : /*****************************************************************************
2078 : * Check for "pseudo-constant" clauses
2079 : *****************************************************************************/
2080 :
2081 : /*
2082 : * is_pseudo_constant_clause
2083 : * Detect whether an expression is "pseudo constant", ie, it contains no
2084 : * variables of the current query level and no uses of volatile functions.
2085 : * Such an expr is not necessarily a true constant: it can still contain
2086 : * Params and outer-level Vars, not to mention functions whose results
2087 : * may vary from one statement to the next. However, the expr's value
2088 : * will be constant over any one scan of the current query, so it can be
2089 : * used as, eg, an indexscan key. (Actually, the condition for indexscan
2090 : * keys is weaker than this; see is_pseudo_constant_for_index().)
2091 : *
2092 : * CAUTION: this function omits to test for one very important class of
2093 : * not-constant expressions, namely aggregates (Aggrefs). In current usage
2094 : * this is only applied to WHERE clauses and so a check for Aggrefs would be
2095 : * a waste of cycles; but be sure to also check contain_agg_clause() if you
2096 : * want to know about pseudo-constness in other contexts. The same goes
2097 : * for window functions (WindowFuncs).
2098 : */
2099 : bool
2100 2916 : is_pseudo_constant_clause(Node *clause)
2101 : {
2102 : /*
2103 : * We could implement this check in one recursive scan. But since the
2104 : * check for volatile functions is both moderately expensive and unlikely
2105 : * to fail, it seems better to look for Vars first and only check for
2106 : * volatile functions if we find no Vars.
2107 : */
2108 2916 : if (!contain_var_clause(clause) &&
2109 2916 : !contain_volatile_functions(clause))
2110 2916 : return true;
2111 0 : return false;
2112 : }
2113 :
2114 : /*
2115 : * is_pseudo_constant_clause_relids
2116 : * Same as above, except caller already has available the var membership
2117 : * of the expression; this lets us avoid the contain_var_clause() scan.
2118 : */
2119 : bool
2120 259843 : is_pseudo_constant_clause_relids(Node *clause, Relids relids)
2121 : {
2122 259843 : if (bms_is_empty(relids) &&
2123 255848 : !contain_volatile_functions(clause))
2124 255848 : return true;
2125 3995 : return false;
2126 : }
2127 :
2128 :
2129 : /*****************************************************************************
2130 : * *
2131 : * General clause-manipulating routines *
2132 : * *
2133 : *****************************************************************************/
2134 :
2135 : /*
2136 : * NumRelids
2137 : * (formerly clause_relids)
2138 : *
2139 : * Returns the number of different base relations referenced in 'clause'.
2140 : */
2141 : int
2142 891 : NumRelids(PlannerInfo *root, Node *clause)
2143 : {
2144 : int result;
2145 891 : Relids varnos = pull_varnos(root, clause);
2146 :
2147 891 : varnos = bms_del_members(varnos, root->outer_join_rels);
2148 891 : result = bms_num_members(varnos);
2149 891 : bms_free(varnos);
2150 891 : return result;
2151 : }
2152 :
2153 : /*
2154 : * CommuteOpExpr: commute a binary operator clause
2155 : *
2156 : * XXX the clause is destructively modified!
2157 : */
2158 : void
2159 11592 : CommuteOpExpr(OpExpr *clause)
2160 : {
2161 : Oid opoid;
2162 : Node *temp;
2163 :
2164 : /* Sanity checks: caller is at fault if these fail */
2165 23184 : if (!is_opclause(clause) ||
2166 11592 : list_length(clause->args) != 2)
2167 0 : elog(ERROR, "cannot commute non-binary-operator clause");
2168 :
2169 11592 : opoid = get_commutator(clause->opno);
2170 :
2171 11592 : if (!OidIsValid(opoid))
2172 0 : elog(ERROR, "could not find commutator for operator %u",
2173 : clause->opno);
2174 :
2175 : /*
2176 : * modify the clause in-place!
2177 : */
2178 11592 : clause->opno = opoid;
2179 11592 : clause->opfuncid = InvalidOid;
2180 : /* opresulttype, opretset, opcollid, inputcollid need not change */
2181 :
2182 11592 : temp = linitial(clause->args);
2183 11592 : linitial(clause->args) = lsecond(clause->args);
2184 11592 : lsecond(clause->args) = temp;
2185 11592 : }
2186 :
2187 : /*
2188 : * Helper for eval_const_expressions: check that datatype of an attribute
2189 : * is still what it was when the expression was parsed. This is needed to
2190 : * guard against improper simplification after ALTER COLUMN TYPE. (XXX we
2191 : * may well need to make similar checks elsewhere?)
2192 : *
2193 : * rowtypeid may come from a whole-row Var, and therefore it can be a domain
2194 : * over composite, but for this purpose we only care about checking the type
2195 : * of a contained field.
2196 : */
2197 : static bool
2198 360 : rowtype_field_matches(Oid rowtypeid, int fieldnum,
2199 : Oid expectedtype, int32 expectedtypmod,
2200 : Oid expectedcollation)
2201 : {
2202 : TupleDesc tupdesc;
2203 : Form_pg_attribute attr;
2204 :
2205 : /* No issue for RECORD, since there is no way to ALTER such a type */
2206 360 : if (rowtypeid == RECORDOID)
2207 28 : return true;
2208 332 : tupdesc = lookup_rowtype_tupdesc_domain(rowtypeid, -1, false);
2209 332 : if (fieldnum <= 0 || fieldnum > tupdesc->natts)
2210 : {
2211 0 : ReleaseTupleDesc(tupdesc);
2212 0 : return false;
2213 : }
2214 332 : attr = TupleDescAttr(tupdesc, fieldnum - 1);
2215 332 : if (attr->attisdropped ||
2216 332 : attr->atttypid != expectedtype ||
2217 332 : attr->atttypmod != expectedtypmod ||
2218 332 : attr->attcollation != expectedcollation)
2219 : {
2220 0 : ReleaseTupleDesc(tupdesc);
2221 0 : return false;
2222 : }
2223 332 : ReleaseTupleDesc(tupdesc);
2224 332 : return true;
2225 : }
2226 :
2227 :
2228 : /*--------------------
2229 : * eval_const_expressions
2230 : *
2231 : * Reduce any recognizably constant subexpressions of the given
2232 : * expression tree, for example "2 + 2" => "4". More interestingly,
2233 : * we can reduce certain boolean expressions even when they contain
2234 : * non-constant subexpressions: "x OR true" => "true" no matter what
2235 : * the subexpression x is. (XXX We assume that no such subexpression
2236 : * will have important side-effects, which is not necessarily a good
2237 : * assumption in the presence of user-defined functions; do we need a
2238 : * pg_proc flag that prevents discarding the execution of a function?)
2239 : *
2240 : * We do understand that certain functions may deliver non-constant
2241 : * results even with constant inputs, "nextval()" being the classic
2242 : * example. Functions that are not marked "immutable" in pg_proc
2243 : * will not be pre-evaluated here, although we will reduce their
2244 : * arguments as far as possible.
2245 : *
2246 : * Whenever a function is eliminated from the expression by means of
2247 : * constant-expression evaluation or inlining, we add the function to
2248 : * root->glob->invalItems. This ensures the plan is known to depend on
2249 : * such functions, even though they aren't referenced anymore.
2250 : *
2251 : * We assume that the tree has already been type-checked and contains
2252 : * only operators and functions that are reasonable to try to execute.
2253 : *
2254 : * NOTE: "root" can be passed as NULL if the caller never wants to do any
2255 : * Param substitutions nor receive info about inlined functions nor reduce
2256 : * NullTest for Vars to constant true or constant false.
2257 : *
2258 : * NOTE: the planner assumes that this will always flatten nested AND and
2259 : * OR clauses into N-argument form. See comments in prepqual.c.
2260 : *
2261 : * NOTE: another critical effect is that any function calls that require
2262 : * default arguments will be expanded, and named-argument calls will be
2263 : * converted to positional notation. The executor won't handle either.
2264 : *--------------------
2265 : */
2266 : Node *
2267 666345 : eval_const_expressions(PlannerInfo *root, Node *node)
2268 : {
2269 : eval_const_expressions_context context;
2270 :
2271 666345 : if (root)
2272 538735 : context.boundParams = root->glob->boundParams; /* bound Params */
2273 : else
2274 127610 : context.boundParams = NULL;
2275 666345 : context.root = root; /* for inlined-function dependencies */
2276 666345 : context.active_fns = NIL; /* nothing being recursively simplified */
2277 666345 : context.case_val = NULL; /* no CASE being examined */
2278 666345 : context.estimate = false; /* safe transformations only */
2279 666345 : return eval_const_expressions_mutator(node, &context);
2280 : }
2281 :
2282 : #define MIN_ARRAY_SIZE_FOR_HASHED_SAOP 9
2283 : /*--------------------
2284 : * convert_saop_to_hashed_saop
2285 : *
2286 : * Recursively search 'node' for ScalarArrayOpExprs and fill in the hash
2287 : * function for any ScalarArrayOpExpr that looks like it would be useful to
2288 : * evaluate using a hash table rather than a linear search.
2289 : *
2290 : * We'll use a hash table if all of the following conditions are met:
2291 : * 1. The 2nd argument of the array contain only Consts.
2292 : * 2. useOr is true or there is a valid negator operator for the
2293 : * ScalarArrayOpExpr's opno.
2294 : * 3. There's valid hash function for both left and righthand operands and
2295 : * these hash functions are the same.
2296 : * 4. If the array contains enough elements for us to consider it to be
2297 : * worthwhile using a hash table rather than a linear search.
2298 : */
2299 : void
2300 470070 : convert_saop_to_hashed_saop(Node *node)
2301 : {
2302 470070 : (void) convert_saop_to_hashed_saop_walker(node, NULL);
2303 470070 : }
2304 :
2305 : static bool
2306 3447293 : convert_saop_to_hashed_saop_walker(Node *node, void *context)
2307 : {
2308 3447293 : if (node == NULL)
2309 77661 : return false;
2310 :
2311 3369632 : if (IsA(node, ScalarArrayOpExpr))
2312 : {
2313 17505 : ScalarArrayOpExpr *saop = (ScalarArrayOpExpr *) node;
2314 17505 : Expr *arrayarg = (Expr *) lsecond(saop->args);
2315 : Oid lefthashfunc;
2316 : Oid righthashfunc;
2317 :
2318 17505 : if (arrayarg && IsA(arrayarg, Const) &&
2319 9540 : !((Const *) arrayarg)->constisnull)
2320 : {
2321 9525 : if (saop->useOr)
2322 : {
2323 8226 : if (get_op_hash_functions(saop->opno, &lefthashfunc, &righthashfunc) &&
2324 8059 : lefthashfunc == righthashfunc)
2325 : {
2326 8046 : Datum arrdatum = ((Const *) arrayarg)->constvalue;
2327 8046 : ArrayType *arr = (ArrayType *) DatumGetPointer(arrdatum);
2328 : int nitems;
2329 :
2330 : /*
2331 : * Only fill in the hash functions if the array looks
2332 : * large enough for it to be worth hashing instead of
2333 : * doing a linear search.
2334 : */
2335 8046 : nitems = ArrayGetNItems(ARR_NDIM(arr), ARR_DIMS(arr));
2336 :
2337 8046 : if (nitems >= MIN_ARRAY_SIZE_FOR_HASHED_SAOP)
2338 : {
2339 : /* Looks good. Fill in the hash functions */
2340 221 : saop->hashfuncid = lefthashfunc;
2341 : }
2342 9260 : return false;
2343 : }
2344 : }
2345 : else /* !saop->useOr */
2346 : {
2347 1299 : Oid negator = get_negator(saop->opno);
2348 :
2349 : /*
2350 : * Check if this is a NOT IN using an operator whose negator
2351 : * is hashable. If so we can still build a hash table and
2352 : * just ensure the lookup items are not in the hash table.
2353 : */
2354 2598 : if (OidIsValid(negator) &&
2355 1299 : get_op_hash_functions(negator, &lefthashfunc, &righthashfunc) &&
2356 1214 : lefthashfunc == righthashfunc)
2357 : {
2358 1214 : Datum arrdatum = ((Const *) arrayarg)->constvalue;
2359 1214 : ArrayType *arr = (ArrayType *) DatumGetPointer(arrdatum);
2360 : int nitems;
2361 :
2362 : /*
2363 : * Only fill in the hash functions if the array looks
2364 : * large enough for it to be worth hashing instead of
2365 : * doing a linear search.
2366 : */
2367 1214 : nitems = ArrayGetNItems(ARR_NDIM(arr), ARR_DIMS(arr));
2368 :
2369 1214 : if (nitems >= MIN_ARRAY_SIZE_FOR_HASHED_SAOP)
2370 : {
2371 : /* Looks good. Fill in the hash functions */
2372 35 : saop->hashfuncid = lefthashfunc;
2373 :
2374 : /*
2375 : * Also set the negfuncid. The executor will need
2376 : * that to perform hashtable lookups.
2377 : */
2378 35 : saop->negfuncid = get_opcode(negator);
2379 : }
2380 1214 : return false;
2381 : }
2382 : }
2383 : }
2384 : }
2385 :
2386 3360372 : return expression_tree_walker(node, convert_saop_to_hashed_saop_walker, NULL);
2387 : }
2388 :
2389 :
2390 : /*--------------------
2391 : * estimate_expression_value
2392 : *
2393 : * This function attempts to estimate the value of an expression for
2394 : * planning purposes. It is in essence a more aggressive version of
2395 : * eval_const_expressions(): we will perform constant reductions that are
2396 : * not necessarily 100% safe, but are reasonable for estimation purposes.
2397 : *
2398 : * Currently the extra steps that are taken in this mode are:
2399 : * 1. Substitute values for Params, where a bound Param value has been made
2400 : * available by the caller of planner(), even if the Param isn't marked
2401 : * constant. This effectively means that we plan using the first supplied
2402 : * value of the Param.
2403 : * 2. Fold stable, as well as immutable, functions to constants.
2404 : * 3. Reduce PlaceHolderVar nodes to their contained expressions.
2405 : *--------------------
2406 : */
2407 : Node *
2408 514972 : estimate_expression_value(PlannerInfo *root, Node *node)
2409 : {
2410 : eval_const_expressions_context context;
2411 :
2412 514972 : context.boundParams = root->glob->boundParams; /* bound Params */
2413 : /* we do not need to mark the plan as depending on inlined functions */
2414 514972 : context.root = NULL;
2415 514972 : context.active_fns = NIL; /* nothing being recursively simplified */
2416 514972 : context.case_val = NULL; /* no CASE being examined */
2417 514972 : context.estimate = true; /* unsafe transformations OK */
2418 514972 : return eval_const_expressions_mutator(node, &context);
2419 : }
2420 :
2421 : /*
2422 : * The generic case in eval_const_expressions_mutator is to recurse using
2423 : * expression_tree_mutator, which will copy the given node unchanged but
2424 : * const-simplify its arguments (if any) as far as possible. If the node
2425 : * itself does immutable processing, and each of its arguments were reduced
2426 : * to a Const, we can then reduce it to a Const using evaluate_expr. (Some
2427 : * node types need more complicated logic; for example, a CASE expression
2428 : * might be reducible to a constant even if not all its subtrees are.)
2429 : */
2430 : #define ece_generic_processing(node) \
2431 : expression_tree_mutator((Node *) (node), eval_const_expressions_mutator, \
2432 : context)
2433 :
2434 : /*
2435 : * Check whether all arguments of the given node were reduced to Consts.
2436 : * By going directly to expression_tree_walker, contain_non_const_walker
2437 : * is not applied to the node itself, only to its children.
2438 : */
2439 : #define ece_all_arguments_const(node) \
2440 : (!expression_tree_walker((Node *) (node), contain_non_const_walker, NULL))
2441 :
2442 : /* Generic macro for applying evaluate_expr */
2443 : #define ece_evaluate_expr(node) \
2444 : ((Node *) evaluate_expr((Expr *) (node), \
2445 : exprType((Node *) (node)), \
2446 : exprTypmod((Node *) (node)), \
2447 : exprCollation((Node *) (node))))
2448 :
2449 : /*
2450 : * Recursive guts of eval_const_expressions/estimate_expression_value
2451 : */
2452 : static Node *
2453 5131018 : eval_const_expressions_mutator(Node *node,
2454 : eval_const_expressions_context *context)
2455 : {
2456 :
2457 : /* since this function recurses, it could be driven to stack overflow */
2458 5131018 : check_stack_depth();
2459 :
2460 5131018 : if (node == NULL)
2461 216449 : return NULL;
2462 4914569 : switch (nodeTag(node))
2463 : {
2464 78531 : case T_Param:
2465 : {
2466 78531 : Param *param = (Param *) node;
2467 78531 : ParamListInfo paramLI = context->boundParams;
2468 :
2469 : /* Look to see if we've been given a value for this Param */
2470 78531 : if (param->paramkind == PARAM_EXTERN &&
2471 27780 : paramLI != NULL &&
2472 27780 : param->paramid > 0 &&
2473 27780 : param->paramid <= paramLI->numParams)
2474 : {
2475 : ParamExternData *prm;
2476 : ParamExternData prmdata;
2477 :
2478 : /*
2479 : * Give hook a chance in case parameter is dynamic. Tell
2480 : * it that this fetch is speculative, so it should avoid
2481 : * erroring out if parameter is unavailable.
2482 : */
2483 27780 : if (paramLI->paramFetch != NULL)
2484 3731 : prm = paramLI->paramFetch(paramLI, param->paramid,
2485 : true, &prmdata);
2486 : else
2487 24049 : prm = ¶mLI->params[param->paramid - 1];
2488 :
2489 : /*
2490 : * We don't just check OidIsValid, but insist that the
2491 : * fetched type match the Param, just in case the hook did
2492 : * something unexpected. No need to throw an error here
2493 : * though; leave that for runtime.
2494 : */
2495 27780 : if (OidIsValid(prm->ptype) &&
2496 27780 : prm->ptype == param->paramtype)
2497 : {
2498 : /* OK to substitute parameter value? */
2499 27779 : if (context->estimate ||
2500 27779 : (prm->pflags & PARAM_FLAG_CONST))
2501 : {
2502 : /*
2503 : * Return a Const representing the param value.
2504 : * Must copy pass-by-ref datatypes, since the
2505 : * Param might be in a memory context
2506 : * shorter-lived than our output plan should be.
2507 : */
2508 : int16 typLen;
2509 : bool typByVal;
2510 : Datum pval;
2511 : Const *con;
2512 :
2513 27779 : get_typlenbyval(param->paramtype,
2514 : &typLen, &typByVal);
2515 27779 : if (prm->isnull || typByVal)
2516 17963 : pval = prm->value;
2517 : else
2518 9816 : pval = datumCopy(prm->value, typByVal, typLen);
2519 27779 : con = makeConst(param->paramtype,
2520 : param->paramtypmod,
2521 : param->paramcollid,
2522 : (int) typLen,
2523 : pval,
2524 27779 : prm->isnull,
2525 : typByVal);
2526 27779 : con->location = param->location;
2527 27779 : return (Node *) con;
2528 : }
2529 : }
2530 : }
2531 :
2532 : /*
2533 : * Not replaceable, so just copy the Param (no need to
2534 : * recurse)
2535 : */
2536 50752 : return (Node *) copyObject(param);
2537 : }
2538 1854 : case T_WindowFunc:
2539 : {
2540 1854 : WindowFunc *expr = (WindowFunc *) node;
2541 1854 : Oid funcid = expr->winfnoid;
2542 : List *args;
2543 : Expr *aggfilter;
2544 : HeapTuple func_tuple;
2545 : WindowFunc *newexpr;
2546 :
2547 : /*
2548 : * We can't really simplify a WindowFunc node, but we mustn't
2549 : * just fall through to the default processing, because we
2550 : * have to apply expand_function_arguments to its argument
2551 : * list. That takes care of inserting default arguments and
2552 : * expanding named-argument notation.
2553 : */
2554 1854 : func_tuple = SearchSysCache1(PROCOID, ObjectIdGetDatum(funcid));
2555 1854 : if (!HeapTupleIsValid(func_tuple))
2556 0 : elog(ERROR, "cache lookup failed for function %u", funcid);
2557 :
2558 1854 : args = expand_function_arguments(expr->args,
2559 : false, expr->wintype,
2560 : func_tuple);
2561 :
2562 1854 : ReleaseSysCache(func_tuple);
2563 :
2564 : /* Now, recursively simplify the args (which are a List) */
2565 : args = (List *)
2566 1854 : expression_tree_mutator((Node *) args,
2567 : eval_const_expressions_mutator,
2568 : context);
2569 : /* ... and the filter expression, which isn't */
2570 : aggfilter = (Expr *)
2571 1854 : eval_const_expressions_mutator((Node *) expr->aggfilter,
2572 : context);
2573 :
2574 : /* And build the replacement WindowFunc node */
2575 1854 : newexpr = makeNode(WindowFunc);
2576 1854 : newexpr->winfnoid = expr->winfnoid;
2577 1854 : newexpr->wintype = expr->wintype;
2578 1854 : newexpr->wincollid = expr->wincollid;
2579 1854 : newexpr->inputcollid = expr->inputcollid;
2580 1854 : newexpr->args = args;
2581 1854 : newexpr->aggfilter = aggfilter;
2582 1854 : newexpr->runCondition = expr->runCondition;
2583 1854 : newexpr->winref = expr->winref;
2584 1854 : newexpr->winstar = expr->winstar;
2585 1854 : newexpr->winagg = expr->winagg;
2586 1854 : newexpr->ignore_nulls = expr->ignore_nulls;
2587 1854 : newexpr->location = expr->location;
2588 :
2589 1854 : return (Node *) newexpr;
2590 : }
2591 288189 : case T_FuncExpr:
2592 : {
2593 288189 : FuncExpr *expr = (FuncExpr *) node;
2594 288189 : List *args = expr->args;
2595 : Expr *simple;
2596 : FuncExpr *newexpr;
2597 :
2598 : /*
2599 : * Code for op/func reduction is pretty bulky, so split it out
2600 : * as a separate function. Note: exprTypmod normally returns
2601 : * -1 for a FuncExpr, but not when the node is recognizably a
2602 : * length coercion; we want to preserve the typmod in the
2603 : * eventual Const if so.
2604 : */
2605 288189 : simple = simplify_function(expr->funcid,
2606 : expr->funcresulttype,
2607 : exprTypmod(node),
2608 : expr->funccollid,
2609 : expr->inputcollid,
2610 : &args,
2611 288189 : expr->funcvariadic,
2612 : true,
2613 : true,
2614 : context);
2615 286791 : if (simple) /* successfully simplified it */
2616 83223 : return (Node *) simple;
2617 :
2618 : /*
2619 : * The expression cannot be simplified any further, so build
2620 : * and return a replacement FuncExpr node using the
2621 : * possibly-simplified arguments. Note that we have also
2622 : * converted the argument list to positional notation.
2623 : */
2624 203568 : newexpr = makeNode(FuncExpr);
2625 203568 : newexpr->funcid = expr->funcid;
2626 203568 : newexpr->funcresulttype = expr->funcresulttype;
2627 203568 : newexpr->funcretset = expr->funcretset;
2628 203568 : newexpr->funcvariadic = expr->funcvariadic;
2629 203568 : newexpr->funcformat = expr->funcformat;
2630 203568 : newexpr->funccollid = expr->funccollid;
2631 203568 : newexpr->inputcollid = expr->inputcollid;
2632 203568 : newexpr->args = args;
2633 203568 : newexpr->location = expr->location;
2634 203568 : return (Node *) newexpr;
2635 : }
2636 26320 : case T_Aggref:
2637 26320 : node = ece_generic_processing(node);
2638 26320 : if (context->root != NULL)
2639 26320 : return simplify_aggref((Aggref *) node, context);
2640 0 : return node;
2641 393854 : case T_OpExpr:
2642 : {
2643 393854 : OpExpr *expr = (OpExpr *) node;
2644 393854 : List *args = expr->args;
2645 : Expr *simple;
2646 : OpExpr *newexpr;
2647 :
2648 : /*
2649 : * Need to get OID of underlying function. Okay to scribble
2650 : * on input to this extent.
2651 : */
2652 393854 : set_opfuncid(expr);
2653 :
2654 : /*
2655 : * Code for op/func reduction is pretty bulky, so split it out
2656 : * as a separate function.
2657 : */
2658 393854 : simple = simplify_function(expr->opfuncid,
2659 : expr->opresulttype, -1,
2660 : expr->opcollid,
2661 : expr->inputcollid,
2662 : &args,
2663 : false,
2664 : true,
2665 : true,
2666 : context);
2667 393263 : if (simple) /* successfully simplified it */
2668 13895 : return (Node *) simple;
2669 :
2670 : /*
2671 : * If the operator is boolean equality or inequality, we know
2672 : * how to simplify cases involving one constant and one
2673 : * non-constant argument.
2674 : */
2675 379368 : if (expr->opno == BooleanEqualOperator ||
2676 378086 : expr->opno == BooleanNotEqualOperator)
2677 : {
2678 1366 : simple = (Expr *) simplify_boolean_equality(expr->opno,
2679 : args);
2680 1366 : if (simple) /* successfully simplified it */
2681 958 : return (Node *) simple;
2682 : }
2683 :
2684 : /*
2685 : * The expression cannot be simplified any further, so build
2686 : * and return a replacement OpExpr node using the
2687 : * possibly-simplified arguments.
2688 : */
2689 378410 : newexpr = makeNode(OpExpr);
2690 378410 : newexpr->opno = expr->opno;
2691 378410 : newexpr->opfuncid = expr->opfuncid;
2692 378410 : newexpr->opresulttype = expr->opresulttype;
2693 378410 : newexpr->opretset = expr->opretset;
2694 378410 : newexpr->opcollid = expr->opcollid;
2695 378410 : newexpr->inputcollid = expr->inputcollid;
2696 378410 : newexpr->args = args;
2697 378410 : newexpr->location = expr->location;
2698 378410 : return (Node *) newexpr;
2699 : }
2700 809 : case T_DistinctExpr:
2701 : {
2702 809 : DistinctExpr *expr = (DistinctExpr *) node;
2703 : List *args;
2704 : ListCell *arg;
2705 809 : bool has_null_input = false;
2706 809 : bool all_null_input = true;
2707 809 : bool has_nonconst_input = false;
2708 809 : bool has_nullable_nonconst = false;
2709 : Expr *simple;
2710 : DistinctExpr *newexpr;
2711 :
2712 : /*
2713 : * Reduce constants in the DistinctExpr's arguments. We know
2714 : * args is either NIL or a List node, so we can call
2715 : * expression_tree_mutator directly rather than recursing to
2716 : * self.
2717 : */
2718 809 : args = (List *) expression_tree_mutator((Node *) expr->args,
2719 : eval_const_expressions_mutator,
2720 : context);
2721 :
2722 : /*
2723 : * We must do our own check for NULLs because DistinctExpr has
2724 : * different results for NULL input than the underlying
2725 : * operator does. We also check if any non-constant input is
2726 : * potentially nullable.
2727 : */
2728 2427 : foreach(arg, args)
2729 : {
2730 1618 : if (IsA(lfirst(arg), Const))
2731 : {
2732 245 : has_null_input |= ((Const *) lfirst(arg))->constisnull;
2733 245 : all_null_input &= ((Const *) lfirst(arg))->constisnull;
2734 : }
2735 : else
2736 : {
2737 1373 : has_nonconst_input = true;
2738 1373 : all_null_input = false;
2739 :
2740 1373 : if (!has_nullable_nonconst &&
2741 797 : !expr_is_nonnullable(context->root,
2742 797 : (Expr *) lfirst(arg), false))
2743 746 : has_nullable_nonconst = true;
2744 : }
2745 : }
2746 :
2747 809 : if (!has_nonconst_input)
2748 : {
2749 : /*
2750 : * All inputs are constants. We can optimize this out
2751 : * completely.
2752 : */
2753 :
2754 : /* all nulls? then not distinct */
2755 27 : if (all_null_input)
2756 6 : return makeBoolConst(false, false);
2757 :
2758 : /* one null? then distinct */
2759 21 : if (has_null_input)
2760 9 : return makeBoolConst(true, false);
2761 :
2762 : /* otherwise try to evaluate the '=' operator */
2763 : /* (NOT okay to try to inline it, though!) */
2764 :
2765 : /*
2766 : * Need to get OID of underlying function. Okay to
2767 : * scribble on input to this extent.
2768 : */
2769 12 : set_opfuncid((OpExpr *) expr); /* rely on struct
2770 : * equivalence */
2771 :
2772 : /*
2773 : * Code for op/func reduction is pretty bulky, so split it
2774 : * out as a separate function.
2775 : */
2776 12 : simple = simplify_function(expr->opfuncid,
2777 : expr->opresulttype, -1,
2778 : expr->opcollid,
2779 : expr->inputcollid,
2780 : &args,
2781 : false,
2782 : false,
2783 : false,
2784 : context);
2785 12 : if (simple) /* successfully simplified it */
2786 : {
2787 : /*
2788 : * Since the underlying operator is "=", must negate
2789 : * its result
2790 : */
2791 12 : Const *csimple = castNode(Const, simple);
2792 :
2793 12 : csimple->constvalue =
2794 12 : BoolGetDatum(!DatumGetBool(csimple->constvalue));
2795 12 : return (Node *) csimple;
2796 : }
2797 : }
2798 782 : else if (!has_nullable_nonconst)
2799 : {
2800 : /*
2801 : * There are non-constant inputs, but since all of them
2802 : * are proven non-nullable, "IS DISTINCT FROM" semantics
2803 : * are much simpler.
2804 : */
2805 :
2806 : OpExpr *eqexpr;
2807 :
2808 : /*
2809 : * If one input is an explicit NULL constant, and the
2810 : * other is a non-nullable expression, the result is
2811 : * always TRUE.
2812 : */
2813 36 : if (has_null_input)
2814 12 : return makeBoolConst(true, false);
2815 :
2816 : /*
2817 : * Otherwise, both inputs are known non-nullable. In this
2818 : * case, "IS DISTINCT FROM" is equivalent to the standard
2819 : * inequality operator (usually "<>"). We convert this to
2820 : * an OpExpr, which is a more efficient representation for
2821 : * the planner. It can enable the use of partial indexes
2822 : * and constraint exclusion. Furthermore, if the clause
2823 : * is negated (ie, "IS NOT DISTINCT FROM"), the resulting
2824 : * "=" operator can allow the planner to use index scans,
2825 : * merge joins, hash joins, and EC-based qual deductions.
2826 : */
2827 24 : eqexpr = makeNode(OpExpr);
2828 24 : eqexpr->opno = expr->opno;
2829 24 : eqexpr->opfuncid = expr->opfuncid;
2830 24 : eqexpr->opresulttype = BOOLOID;
2831 24 : eqexpr->opretset = expr->opretset;
2832 24 : eqexpr->opcollid = expr->opcollid;
2833 24 : eqexpr->inputcollid = expr->inputcollid;
2834 24 : eqexpr->args = args;
2835 24 : eqexpr->location = expr->location;
2836 :
2837 24 : return eval_const_expressions_mutator(negate_clause((Node *) eqexpr),
2838 : context);
2839 : }
2840 746 : else if (has_null_input)
2841 : {
2842 : /*
2843 : * One input is a nullable non-constant expression, and
2844 : * the other is an explicit NULL constant. We can
2845 : * transform this to a NullTest with !argisrow, which is
2846 : * much more amenable to optimization.
2847 : */
2848 :
2849 24 : NullTest *nt = makeNode(NullTest);
2850 :
2851 48 : nt->arg = (Expr *) (IsA(linitial(args), Const) ?
2852 24 : lsecond(args) : linitial(args));
2853 24 : nt->nulltesttype = IS_NOT_NULL;
2854 :
2855 : /*
2856 : * argisrow = false is correct whether or not arg is
2857 : * composite
2858 : */
2859 24 : nt->argisrow = false;
2860 24 : nt->location = expr->location;
2861 :
2862 24 : return eval_const_expressions_mutator((Node *) nt, context);
2863 : }
2864 :
2865 : /*
2866 : * The expression cannot be simplified any further, so build
2867 : * and return a replacement DistinctExpr node using the
2868 : * possibly-simplified arguments.
2869 : */
2870 722 : newexpr = makeNode(DistinctExpr);
2871 722 : newexpr->opno = expr->opno;
2872 722 : newexpr->opfuncid = expr->opfuncid;
2873 722 : newexpr->opresulttype = expr->opresulttype;
2874 722 : newexpr->opretset = expr->opretset;
2875 722 : newexpr->opcollid = expr->opcollid;
2876 722 : newexpr->inputcollid = expr->inputcollid;
2877 722 : newexpr->args = args;
2878 722 : newexpr->location = expr->location;
2879 722 : return (Node *) newexpr;
2880 : }
2881 501 : case T_NullIfExpr:
2882 : {
2883 : NullIfExpr *expr;
2884 : ListCell *arg;
2885 501 : bool has_nonconst_input = false;
2886 :
2887 : /* Copy the node and const-simplify its arguments */
2888 501 : expr = (NullIfExpr *) ece_generic_processing(node);
2889 :
2890 : /* If either argument is NULL they can't be equal */
2891 1500 : foreach(arg, expr->args)
2892 : {
2893 1002 : if (!IsA(lfirst(arg), Const))
2894 485 : has_nonconst_input = true;
2895 517 : else if (((Const *) lfirst(arg))->constisnull)
2896 3 : return (Node *) linitial(expr->args);
2897 : }
2898 :
2899 : /*
2900 : * Need to get OID of underlying function before checking if
2901 : * the function is OK to evaluate.
2902 : */
2903 498 : set_opfuncid((OpExpr *) expr);
2904 :
2905 517 : if (!has_nonconst_input &&
2906 19 : ece_function_is_safe(expr->opfuncid, context))
2907 19 : return ece_evaluate_expr(expr);
2908 :
2909 479 : return (Node *) expr;
2910 : }
2911 20005 : case T_ScalarArrayOpExpr:
2912 : {
2913 : ScalarArrayOpExpr *saop;
2914 :
2915 : /* Copy the node and const-simplify its arguments */
2916 20005 : saop = (ScalarArrayOpExpr *) ece_generic_processing(node);
2917 :
2918 : /* Make sure we know underlying function */
2919 20005 : set_sa_opfuncid(saop);
2920 :
2921 : /*
2922 : * If all arguments are Consts, and it's a safe function, we
2923 : * can fold to a constant
2924 : */
2925 20174 : if (ece_all_arguments_const(saop) &&
2926 169 : ece_function_is_safe(saop->opfuncid, context))
2927 169 : return ece_evaluate_expr(saop);
2928 19836 : return (Node *) saop;
2929 : }
2930 104051 : case T_BoolExpr:
2931 : {
2932 104051 : BoolExpr *expr = (BoolExpr *) node;
2933 :
2934 104051 : switch (expr->boolop)
2935 : {
2936 10446 : case OR_EXPR:
2937 : {
2938 : List *newargs;
2939 10446 : bool haveNull = false;
2940 10446 : bool forceTrue = false;
2941 :
2942 10446 : newargs = simplify_or_arguments(expr->args,
2943 : context,
2944 : &haveNull,
2945 : &forceTrue);
2946 10446 : if (forceTrue)
2947 86 : return makeBoolConst(true, false);
2948 10360 : if (haveNull)
2949 2295 : newargs = lappend(newargs,
2950 2295 : makeBoolConst(false, true));
2951 : /* If all the inputs are FALSE, result is FALSE */
2952 10360 : if (newargs == NIL)
2953 22 : return makeBoolConst(false, false);
2954 :
2955 : /*
2956 : * If only one nonconst-or-NULL input, it's the
2957 : * result
2958 : */
2959 10338 : if (list_length(newargs) == 1)
2960 69 : return (Node *) linitial(newargs);
2961 : /* Else we still need an OR node */
2962 10269 : return (Node *) make_orclause(newargs);
2963 : }
2964 83378 : case AND_EXPR:
2965 : {
2966 : List *newargs;
2967 83378 : bool haveNull = false;
2968 83378 : bool forceFalse = false;
2969 :
2970 83378 : newargs = simplify_and_arguments(expr->args,
2971 : context,
2972 : &haveNull,
2973 : &forceFalse);
2974 83378 : if (forceFalse)
2975 787 : return makeBoolConst(false, false);
2976 82591 : if (haveNull)
2977 3 : newargs = lappend(newargs,
2978 3 : makeBoolConst(false, true));
2979 : /* If all the inputs are TRUE, result is TRUE */
2980 82591 : if (newargs == NIL)
2981 197 : return makeBoolConst(true, false);
2982 :
2983 : /*
2984 : * If only one nonconst-or-NULL input, it's the
2985 : * result
2986 : */
2987 82394 : if (list_length(newargs) == 1)
2988 98 : return (Node *) linitial(newargs);
2989 : /* Else we still need an AND node */
2990 82296 : return (Node *) make_andclause(newargs);
2991 : }
2992 10227 : case NOT_EXPR:
2993 : {
2994 : Node *arg;
2995 :
2996 : Assert(list_length(expr->args) == 1);
2997 10227 : arg = eval_const_expressions_mutator(linitial(expr->args),
2998 : context);
2999 :
3000 : /*
3001 : * Use negate_clause() to see if we can simplify
3002 : * away the NOT.
3003 : */
3004 10227 : return negate_clause(arg);
3005 : }
3006 0 : default:
3007 0 : elog(ERROR, "unrecognized boolop: %d",
3008 : (int) expr->boolop);
3009 : break;
3010 : }
3011 : break;
3012 : }
3013 :
3014 387 : case T_JsonValueExpr:
3015 : {
3016 387 : JsonValueExpr *jve = (JsonValueExpr *) node;
3017 387 : Node *raw_expr = (Node *) jve->raw_expr;
3018 387 : Node *formatted_expr = (Node *) jve->formatted_expr;
3019 :
3020 : /*
3021 : * If we can fold formatted_expr to a constant, we can elide
3022 : * the JsonValueExpr altogether. Otherwise we must process
3023 : * raw_expr too. But JsonFormat is a flat node and requires
3024 : * no simplification, only copying.
3025 : */
3026 387 : formatted_expr = eval_const_expressions_mutator(formatted_expr,
3027 : context);
3028 387 : if (formatted_expr && IsA(formatted_expr, Const))
3029 273 : return formatted_expr;
3030 :
3031 114 : raw_expr = eval_const_expressions_mutator(raw_expr, context);
3032 :
3033 114 : return (Node *) makeJsonValueExpr((Expr *) raw_expr,
3034 : (Expr *) formatted_expr,
3035 114 : copyObject(jve->format));
3036 : }
3037 :
3038 291 : case T_SubPlan:
3039 : case T_AlternativeSubPlan:
3040 :
3041 : /*
3042 : * Return a SubPlan unchanged --- too late to do anything with it.
3043 : *
3044 : * XXX should we ereport() here instead? Probably this routine
3045 : * should never be invoked after SubPlan creation.
3046 : */
3047 291 : return node;
3048 96145 : case T_RelabelType:
3049 : {
3050 96145 : RelabelType *relabel = (RelabelType *) node;
3051 : Node *arg;
3052 :
3053 : /* Simplify the input ... */
3054 96145 : arg = eval_const_expressions_mutator((Node *) relabel->arg,
3055 : context);
3056 : /* ... and attach a new RelabelType node, if needed */
3057 96142 : return applyRelabelType(arg,
3058 : relabel->resulttype,
3059 : relabel->resulttypmod,
3060 : relabel->resultcollid,
3061 : relabel->relabelformat,
3062 : relabel->location,
3063 : true);
3064 : }
3065 17088 : case T_CoerceViaIO:
3066 : {
3067 17088 : CoerceViaIO *expr = (CoerceViaIO *) node;
3068 : List *args;
3069 : Oid outfunc;
3070 : bool outtypisvarlena;
3071 : Oid infunc;
3072 : Oid intypioparam;
3073 : Expr *simple;
3074 : CoerceViaIO *newexpr;
3075 :
3076 : /* Make a List so we can use simplify_function */
3077 17088 : args = list_make1(expr->arg);
3078 :
3079 : /*
3080 : * CoerceViaIO represents calling the source type's output
3081 : * function then the result type's input function. So, try to
3082 : * simplify it as though it were a stack of two such function
3083 : * calls. First we need to know what the functions are.
3084 : *
3085 : * Note that the coercion functions are assumed not to care
3086 : * about input collation, so we just pass InvalidOid for that.
3087 : */
3088 17088 : getTypeOutputInfo(exprType((Node *) expr->arg),
3089 : &outfunc, &outtypisvarlena);
3090 17088 : getTypeInputInfo(expr->resulttype,
3091 : &infunc, &intypioparam);
3092 :
3093 17088 : simple = simplify_function(outfunc,
3094 : CSTRINGOID, -1,
3095 : InvalidOid,
3096 : InvalidOid,
3097 : &args,
3098 : false,
3099 : true,
3100 : true,
3101 : context);
3102 17088 : if (simple) /* successfully simplified output fn */
3103 : {
3104 : /*
3105 : * Input functions may want 1 to 3 arguments. We always
3106 : * supply all three, trusting that nothing downstream will
3107 : * complain.
3108 : */
3109 1249 : args = list_make3(simple,
3110 : makeConst(OIDOID,
3111 : -1,
3112 : InvalidOid,
3113 : sizeof(Oid),
3114 : ObjectIdGetDatum(intypioparam),
3115 : false,
3116 : true),
3117 : makeConst(INT4OID,
3118 : -1,
3119 : InvalidOid,
3120 : sizeof(int32),
3121 : Int32GetDatum(-1),
3122 : false,
3123 : true));
3124 :
3125 1249 : simple = simplify_function(infunc,
3126 : expr->resulttype, -1,
3127 : expr->resultcollid,
3128 : InvalidOid,
3129 : &args,
3130 : false,
3131 : false,
3132 : true,
3133 : context);
3134 1193 : if (simple) /* successfully simplified input fn */
3135 1153 : return (Node *) simple;
3136 : }
3137 :
3138 : /*
3139 : * The expression cannot be simplified any further, so build
3140 : * and return a replacement CoerceViaIO node using the
3141 : * possibly-simplified argument.
3142 : */
3143 15879 : newexpr = makeNode(CoerceViaIO);
3144 15879 : newexpr->arg = (Expr *) linitial(args);
3145 15879 : newexpr->resulttype = expr->resulttype;
3146 15879 : newexpr->resultcollid = expr->resultcollid;
3147 15879 : newexpr->coerceformat = expr->coerceformat;
3148 15879 : newexpr->location = expr->location;
3149 15879 : return (Node *) newexpr;
3150 : }
3151 5390 : case T_ArrayCoerceExpr:
3152 : {
3153 5390 : ArrayCoerceExpr *ac = makeNode(ArrayCoerceExpr);
3154 : Node *save_case_val;
3155 :
3156 : /*
3157 : * Copy the node and const-simplify its arguments. We can't
3158 : * use ece_generic_processing() here because we need to mess
3159 : * with case_val only while processing the elemexpr.
3160 : */
3161 5390 : memcpy(ac, node, sizeof(ArrayCoerceExpr));
3162 5390 : ac->arg = (Expr *)
3163 5390 : eval_const_expressions_mutator((Node *) ac->arg,
3164 : context);
3165 :
3166 : /*
3167 : * Set up for the CaseTestExpr node contained in the elemexpr.
3168 : * We must prevent it from absorbing any outer CASE value.
3169 : */
3170 5390 : save_case_val = context->case_val;
3171 5390 : context->case_val = NULL;
3172 :
3173 5390 : ac->elemexpr = (Expr *)
3174 5390 : eval_const_expressions_mutator((Node *) ac->elemexpr,
3175 : context);
3176 :
3177 5390 : context->case_val = save_case_val;
3178 :
3179 : /*
3180 : * If constant argument and the per-element expression is
3181 : * immutable, we can simplify the whole thing to a constant.
3182 : * Exception: although contain_mutable_functions considers
3183 : * CoerceToDomain immutable for historical reasons, let's not
3184 : * do so here; this ensures coercion to an array-over-domain
3185 : * does not apply the domain's constraints until runtime.
3186 : */
3187 5390 : if (ac->arg && IsA(ac->arg, Const) &&
3188 587 : ac->elemexpr && !IsA(ac->elemexpr, CoerceToDomain) &&
3189 575 : !contain_mutable_functions((Node *) ac->elemexpr))
3190 575 : return ece_evaluate_expr(ac);
3191 :
3192 4815 : return (Node *) ac;
3193 : }
3194 4782 : case T_CollateExpr:
3195 : {
3196 : /*
3197 : * We replace CollateExpr with RelabelType, so as to improve
3198 : * uniformity of expression representation and thus simplify
3199 : * comparison of expressions. Hence this looks very nearly
3200 : * the same as the RelabelType case, and we can apply the same
3201 : * optimizations to avoid unnecessary RelabelTypes.
3202 : */
3203 4782 : CollateExpr *collate = (CollateExpr *) node;
3204 : Node *arg;
3205 :
3206 : /* Simplify the input ... */
3207 4782 : arg = eval_const_expressions_mutator((Node *) collate->arg,
3208 : context);
3209 : /* ... and attach a new RelabelType node, if needed */
3210 4782 : return applyRelabelType(arg,
3211 : exprType(arg),
3212 : exprTypmod(arg),
3213 : collate->collOid,
3214 : COERCE_IMPLICIT_CAST,
3215 : collate->location,
3216 : true);
3217 : }
3218 19559 : case T_CaseExpr:
3219 : {
3220 : /*----------
3221 : * CASE expressions can be simplified if there are constant
3222 : * condition clauses:
3223 : * FALSE (or NULL): drop the alternative
3224 : * TRUE: drop all remaining alternatives
3225 : * If the first non-FALSE alternative is a constant TRUE,
3226 : * we can simplify the entire CASE to that alternative's
3227 : * expression. If there are no non-FALSE alternatives,
3228 : * we simplify the entire CASE to the default result (ELSE).
3229 : *
3230 : * If we have a simple-form CASE with constant test
3231 : * expression, we substitute the constant value for contained
3232 : * CaseTestExpr placeholder nodes, so that we have the
3233 : * opportunity to reduce constant test conditions. For
3234 : * example this allows
3235 : * CASE 0 WHEN 0 THEN 1 ELSE 1/0 END
3236 : * to reduce to 1 rather than drawing a divide-by-0 error.
3237 : * Note that when the test expression is constant, we don't
3238 : * have to include it in the resulting CASE; for example
3239 : * CASE 0 WHEN x THEN y ELSE z END
3240 : * is transformed by the parser to
3241 : * CASE 0 WHEN CaseTestExpr = x THEN y ELSE z END
3242 : * which we can simplify to
3243 : * CASE WHEN 0 = x THEN y ELSE z END
3244 : * It is not necessary for the executor to evaluate the "arg"
3245 : * expression when executing the CASE, since any contained
3246 : * CaseTestExprs that might have referred to it will have been
3247 : * replaced by the constant.
3248 : *----------
3249 : */
3250 19559 : CaseExpr *caseexpr = (CaseExpr *) node;
3251 : CaseExpr *newcase;
3252 : Node *save_case_val;
3253 : Node *newarg;
3254 : List *newargs;
3255 : bool const_true_cond;
3256 19559 : Node *defresult = NULL;
3257 : ListCell *arg;
3258 :
3259 : /* Simplify the test expression, if any */
3260 19559 : newarg = eval_const_expressions_mutator((Node *) caseexpr->arg,
3261 : context);
3262 :
3263 : /* Set up for contained CaseTestExpr nodes */
3264 19559 : save_case_val = context->case_val;
3265 19559 : if (newarg && IsA(newarg, Const))
3266 : {
3267 39 : context->case_val = newarg;
3268 39 : newarg = NULL; /* not needed anymore, see above */
3269 : }
3270 : else
3271 19520 : context->case_val = NULL;
3272 :
3273 : /* Simplify the WHEN clauses */
3274 19559 : newargs = NIL;
3275 19559 : const_true_cond = false;
3276 60838 : foreach(arg, caseexpr->args)
3277 : {
3278 41650 : CaseWhen *oldcasewhen = lfirst_node(CaseWhen, arg);
3279 : Node *casecond;
3280 : Node *caseresult;
3281 :
3282 : /* Simplify this alternative's test condition */
3283 41650 : casecond = eval_const_expressions_mutator((Node *) oldcasewhen->expr,
3284 : context);
3285 :
3286 : /*
3287 : * If the test condition is constant FALSE (or NULL), then
3288 : * drop this WHEN clause completely, without processing
3289 : * the result.
3290 : */
3291 41650 : if (casecond && IsA(casecond, Const))
3292 : {
3293 981 : Const *const_input = (Const *) casecond;
3294 :
3295 981 : if (const_input->constisnull ||
3296 981 : !DatumGetBool(const_input->constvalue))
3297 613 : continue; /* drop alternative with FALSE cond */
3298 : /* Else it's constant TRUE */
3299 368 : const_true_cond = true;
3300 : }
3301 :
3302 : /* Simplify this alternative's result value */
3303 41037 : caseresult = eval_const_expressions_mutator((Node *) oldcasewhen->result,
3304 : context);
3305 :
3306 : /* If non-constant test condition, emit a new WHEN node */
3307 41034 : if (!const_true_cond)
3308 40666 : {
3309 40666 : CaseWhen *newcasewhen = makeNode(CaseWhen);
3310 :
3311 40666 : newcasewhen->expr = (Expr *) casecond;
3312 40666 : newcasewhen->result = (Expr *) caseresult;
3313 40666 : newcasewhen->location = oldcasewhen->location;
3314 40666 : newargs = lappend(newargs, newcasewhen);
3315 40666 : continue;
3316 : }
3317 :
3318 : /*
3319 : * Found a TRUE condition, so none of the remaining
3320 : * alternatives can be reached. We treat the result as
3321 : * the default result.
3322 : */
3323 368 : defresult = caseresult;
3324 368 : break;
3325 : }
3326 :
3327 : /* Simplify the default result, unless we replaced it above */
3328 19556 : if (!const_true_cond)
3329 19188 : defresult = eval_const_expressions_mutator((Node *) caseexpr->defresult,
3330 : context);
3331 :
3332 19556 : context->case_val = save_case_val;
3333 :
3334 : /*
3335 : * If no non-FALSE alternatives, CASE reduces to the default
3336 : * result
3337 : */
3338 19556 : if (newargs == NIL)
3339 584 : return defresult;
3340 : /* Otherwise we need a new CASE node */
3341 18972 : newcase = makeNode(CaseExpr);
3342 18972 : newcase->casetype = caseexpr->casetype;
3343 18972 : newcase->casecollid = caseexpr->casecollid;
3344 18972 : newcase->arg = (Expr *) newarg;
3345 18972 : newcase->args = newargs;
3346 18972 : newcase->defresult = (Expr *) defresult;
3347 18972 : newcase->location = caseexpr->location;
3348 18972 : return (Node *) newcase;
3349 : }
3350 17131 : case T_CaseTestExpr:
3351 : {
3352 : /*
3353 : * If we know a constant test value for the current CASE
3354 : * construct, substitute it for the placeholder. Else just
3355 : * return the placeholder as-is.
3356 : */
3357 17131 : if (context->case_val)
3358 67 : return copyObject(context->case_val);
3359 : else
3360 17064 : return copyObject(node);
3361 : }
3362 33323 : case T_SubscriptingRef:
3363 : case T_ArrayExpr:
3364 : case T_RowExpr:
3365 : case T_MinMaxExpr:
3366 : {
3367 : /*
3368 : * Generic handling for node types whose own processing is
3369 : * known to be immutable, and for which we need no smarts
3370 : * beyond "simplify if all inputs are constants".
3371 : *
3372 : * Treating SubscriptingRef this way assumes that subscripting
3373 : * fetch and assignment are both immutable. This constrains
3374 : * type-specific subscripting implementations; maybe we should
3375 : * relax it someday.
3376 : *
3377 : * Treating MinMaxExpr this way amounts to assuming that the
3378 : * btree comparison function it calls is immutable; see the
3379 : * reasoning in contain_mutable_functions_walker.
3380 : */
3381 :
3382 : /* Copy the node and const-simplify its arguments */
3383 33323 : node = ece_generic_processing(node);
3384 : /* If all arguments are Consts, we can fold to a constant */
3385 33323 : if (ece_all_arguments_const(node))
3386 15724 : return ece_evaluate_expr(node);
3387 17599 : return node;
3388 : }
3389 1356 : case T_CoalesceExpr:
3390 : {
3391 1356 : CoalesceExpr *coalesceexpr = (CoalesceExpr *) node;
3392 : CoalesceExpr *newcoalesce;
3393 : List *newargs;
3394 : ListCell *arg;
3395 :
3396 1356 : newargs = NIL;
3397 3204 : foreach(arg, coalesceexpr->args)
3398 : {
3399 : Node *e;
3400 :
3401 2658 : e = eval_const_expressions_mutator((Node *) lfirst(arg),
3402 : context);
3403 :
3404 : /*
3405 : * We can remove null constants from the list. For a
3406 : * nonnullable expression, if it has not been preceded by
3407 : * any non-null-constant expressions then it is the
3408 : * result. Otherwise, it's the next argument, but we can
3409 : * drop following arguments since they will never be
3410 : * reached.
3411 : */
3412 2658 : if (IsA(e, Const))
3413 : {
3414 796 : if (((Const *) e)->constisnull)
3415 28 : continue; /* drop null constant */
3416 768 : if (newargs == NIL)
3417 79 : return e; /* first expr */
3418 719 : newargs = lappend(newargs, e);
3419 719 : break;
3420 : }
3421 1862 : if (expr_is_nonnullable(context->root, (Expr *) e, false))
3422 : {
3423 42 : if (newargs == NIL)
3424 30 : return e; /* first expr */
3425 12 : newargs = lappend(newargs, e);
3426 12 : break;
3427 : }
3428 :
3429 1820 : newargs = lappend(newargs, e);
3430 : }
3431 :
3432 : /*
3433 : * If all the arguments were constant null, the result is just
3434 : * null
3435 : */
3436 1277 : if (newargs == NIL)
3437 0 : return (Node *) makeNullConst(coalesceexpr->coalescetype,
3438 : -1,
3439 : coalesceexpr->coalescecollid);
3440 :
3441 : /*
3442 : * If there's exactly one surviving argument, we no longer
3443 : * need COALESCE at all: the result is that argument
3444 : */
3445 1277 : if (list_length(newargs) == 1)
3446 9 : return (Node *) linitial(newargs);
3447 :
3448 1268 : newcoalesce = makeNode(CoalesceExpr);
3449 1268 : newcoalesce->coalescetype = coalesceexpr->coalescetype;
3450 1268 : newcoalesce->coalescecollid = coalesceexpr->coalescecollid;
3451 1268 : newcoalesce->args = newargs;
3452 1268 : newcoalesce->location = coalesceexpr->location;
3453 1268 : return (Node *) newcoalesce;
3454 : }
3455 2614 : case T_SQLValueFunction:
3456 : {
3457 : /*
3458 : * All variants of SQLValueFunction are stable, so if we are
3459 : * estimating the expression's value, we should evaluate the
3460 : * current function value. Otherwise just copy.
3461 : */
3462 2614 : SQLValueFunction *svf = (SQLValueFunction *) node;
3463 :
3464 2614 : if (context->estimate)
3465 428 : return (Node *) evaluate_expr((Expr *) svf,
3466 : svf->type,
3467 : svf->typmod,
3468 : InvalidOid);
3469 : else
3470 2186 : return copyObject((Node *) svf);
3471 : }
3472 21582 : case T_FieldSelect:
3473 : {
3474 : /*
3475 : * We can optimize field selection from a whole-row Var into a
3476 : * simple Var. (This case won't be generated directly by the
3477 : * parser, because ParseComplexProjection short-circuits it.
3478 : * But it can arise while simplifying functions.) Also, we
3479 : * can optimize field selection from a RowExpr construct, or
3480 : * of course from a constant.
3481 : *
3482 : * However, replacing a whole-row Var in this way has a
3483 : * pitfall: if we've already built the rel targetlist for the
3484 : * source relation, then the whole-row Var is scheduled to be
3485 : * produced by the relation scan, but the simple Var probably
3486 : * isn't, which will lead to a failure in setrefs.c. This is
3487 : * not a problem when handling simple single-level queries, in
3488 : * which expression simplification always happens first. It
3489 : * is a risk for lateral references from subqueries, though.
3490 : * To avoid such failures, don't optimize uplevel references.
3491 : *
3492 : * We must also check that the declared type of the field is
3493 : * still the same as when the FieldSelect was created --- this
3494 : * can change if someone did ALTER COLUMN TYPE on the rowtype.
3495 : * If it isn't, we skip the optimization; the case will
3496 : * probably fail at runtime, but that's not our problem here.
3497 : */
3498 21582 : FieldSelect *fselect = (FieldSelect *) node;
3499 : FieldSelect *newfselect;
3500 : Node *arg;
3501 :
3502 21582 : arg = eval_const_expressions_mutator((Node *) fselect->arg,
3503 : context);
3504 21582 : if (arg && IsA(arg, Var) &&
3505 19529 : ((Var *) arg)->varattno == InvalidAttrNumber &&
3506 45 : ((Var *) arg)->varlevelsup == 0)
3507 : {
3508 39 : if (rowtype_field_matches(((Var *) arg)->vartype,
3509 39 : fselect->fieldnum,
3510 : fselect->resulttype,
3511 : fselect->resulttypmod,
3512 : fselect->resultcollid))
3513 : {
3514 : Var *newvar;
3515 :
3516 39 : newvar = makeVar(((Var *) arg)->varno,
3517 39 : fselect->fieldnum,
3518 : fselect->resulttype,
3519 : fselect->resulttypmod,
3520 : fselect->resultcollid,
3521 : ((Var *) arg)->varlevelsup);
3522 : /* New Var has same OLD/NEW returning as old one */
3523 39 : newvar->varreturningtype = ((Var *) arg)->varreturningtype;
3524 : /* New Var is nullable by same rels as the old one */
3525 39 : newvar->varnullingrels = ((Var *) arg)->varnullingrels;
3526 39 : return (Node *) newvar;
3527 : }
3528 : }
3529 21543 : if (arg && IsA(arg, RowExpr))
3530 : {
3531 12 : RowExpr *rowexpr = (RowExpr *) arg;
3532 :
3533 24 : if (fselect->fieldnum > 0 &&
3534 12 : fselect->fieldnum <= list_length(rowexpr->args))
3535 : {
3536 12 : Node *fld = (Node *) list_nth(rowexpr->args,
3537 12 : fselect->fieldnum - 1);
3538 :
3539 12 : if (rowtype_field_matches(rowexpr->row_typeid,
3540 12 : fselect->fieldnum,
3541 : fselect->resulttype,
3542 : fselect->resulttypmod,
3543 12 : fselect->resultcollid) &&
3544 24 : fselect->resulttype == exprType(fld) &&
3545 24 : fselect->resulttypmod == exprTypmod(fld) &&
3546 12 : fselect->resultcollid == exprCollation(fld))
3547 12 : return fld;
3548 : }
3549 : }
3550 21531 : newfselect = makeNode(FieldSelect);
3551 21531 : newfselect->arg = (Expr *) arg;
3552 21531 : newfselect->fieldnum = fselect->fieldnum;
3553 21531 : newfselect->resulttype = fselect->resulttype;
3554 21531 : newfselect->resulttypmod = fselect->resulttypmod;
3555 21531 : newfselect->resultcollid = fselect->resultcollid;
3556 21531 : if (arg && IsA(arg, Const))
3557 : {
3558 309 : Const *con = (Const *) arg;
3559 :
3560 309 : if (rowtype_field_matches(con->consttype,
3561 309 : newfselect->fieldnum,
3562 : newfselect->resulttype,
3563 : newfselect->resulttypmod,
3564 : newfselect->resultcollid))
3565 309 : return ece_evaluate_expr(newfselect);
3566 : }
3567 21222 : return (Node *) newfselect;
3568 : }
3569 19744 : case T_NullTest:
3570 : {
3571 19744 : NullTest *ntest = (NullTest *) node;
3572 : NullTest *newntest;
3573 : Node *arg;
3574 :
3575 19744 : arg = eval_const_expressions_mutator((Node *) ntest->arg,
3576 : context);
3577 19743 : if (ntest->argisrow && arg && IsA(arg, RowExpr))
3578 : {
3579 : /*
3580 : * We break ROW(...) IS [NOT] NULL into separate tests on
3581 : * its component fields. This form is usually more
3582 : * efficient to evaluate, as well as being more amenable
3583 : * to optimization.
3584 : */
3585 24 : RowExpr *rarg = (RowExpr *) arg;
3586 24 : List *newargs = NIL;
3587 : ListCell *l;
3588 :
3589 87 : foreach(l, rarg->args)
3590 : {
3591 63 : Node *relem = (Node *) lfirst(l);
3592 :
3593 : /*
3594 : * A constant field refutes the whole NullTest if it's
3595 : * of the wrong nullness; else we can discard it.
3596 : */
3597 63 : if (relem && IsA(relem, Const))
3598 0 : {
3599 0 : Const *carg = (Const *) relem;
3600 :
3601 0 : if (carg->constisnull ?
3602 0 : (ntest->nulltesttype == IS_NOT_NULL) :
3603 0 : (ntest->nulltesttype == IS_NULL))
3604 0 : return makeBoolConst(false, false);
3605 0 : continue;
3606 : }
3607 :
3608 : /*
3609 : * A proven non-nullable field refutes the whole
3610 : * NullTest if the test is IS NULL; else we can
3611 : * discard it.
3612 : */
3613 126 : if (relem &&
3614 63 : expr_is_nonnullable(context->root, (Expr *) relem,
3615 : false))
3616 : {
3617 0 : if (ntest->nulltesttype == IS_NULL)
3618 0 : return makeBoolConst(false, false);
3619 0 : continue;
3620 : }
3621 :
3622 : /*
3623 : * Else, make a scalar (argisrow == false) NullTest
3624 : * for this field. Scalar semantics are required
3625 : * because IS [NOT] NULL doesn't recurse; see comments
3626 : * in ExecEvalRowNullInt().
3627 : */
3628 63 : newntest = makeNode(NullTest);
3629 63 : newntest->arg = (Expr *) relem;
3630 63 : newntest->nulltesttype = ntest->nulltesttype;
3631 63 : newntest->argisrow = false;
3632 63 : newntest->location = ntest->location;
3633 63 : newargs = lappend(newargs, newntest);
3634 : }
3635 : /* If all the inputs were constants, result is TRUE */
3636 24 : if (newargs == NIL)
3637 0 : return makeBoolConst(true, false);
3638 : /* If only one nonconst input, it's the result */
3639 24 : if (list_length(newargs) == 1)
3640 0 : return (Node *) linitial(newargs);
3641 : /* Else we need an AND node */
3642 24 : return (Node *) make_andclause(newargs);
3643 : }
3644 19719 : if (!ntest->argisrow && arg && IsA(arg, Const))
3645 : {
3646 197 : Const *carg = (Const *) arg;
3647 : bool result;
3648 :
3649 197 : switch (ntest->nulltesttype)
3650 : {
3651 164 : case IS_NULL:
3652 164 : result = carg->constisnull;
3653 164 : break;
3654 33 : case IS_NOT_NULL:
3655 33 : result = !carg->constisnull;
3656 33 : break;
3657 0 : default:
3658 0 : elog(ERROR, "unrecognized nulltesttype: %d",
3659 : (int) ntest->nulltesttype);
3660 : result = false; /* keep compiler quiet */
3661 : break;
3662 : }
3663 :
3664 197 : return makeBoolConst(result, false);
3665 : }
3666 38806 : if (!ntest->argisrow && arg &&
3667 19284 : expr_is_nonnullable(context->root, (Expr *) arg, false))
3668 : {
3669 : bool result;
3670 :
3671 333 : switch (ntest->nulltesttype)
3672 : {
3673 80 : case IS_NULL:
3674 80 : result = false;
3675 80 : break;
3676 253 : case IS_NOT_NULL:
3677 253 : result = true;
3678 253 : break;
3679 0 : default:
3680 0 : elog(ERROR, "unrecognized nulltesttype: %d",
3681 : (int) ntest->nulltesttype);
3682 : result = false; /* keep compiler quiet */
3683 : break;
3684 : }
3685 :
3686 333 : return makeBoolConst(result, false);
3687 : }
3688 :
3689 19189 : newntest = makeNode(NullTest);
3690 19189 : newntest->arg = (Expr *) arg;
3691 19189 : newntest->nulltesttype = ntest->nulltesttype;
3692 19189 : newntest->argisrow = ntest->argisrow;
3693 19189 : newntest->location = ntest->location;
3694 19189 : return (Node *) newntest;
3695 : }
3696 1132 : case T_BooleanTest:
3697 : {
3698 : /*
3699 : * This case could be folded into the generic handling used
3700 : * for ArrayExpr etc. But because the simplification logic is
3701 : * so trivial, applying evaluate_expr() to perform it would be
3702 : * a heavy overhead. BooleanTest is probably common enough to
3703 : * justify keeping this bespoke implementation.
3704 : */
3705 1132 : BooleanTest *btest = (BooleanTest *) node;
3706 : BooleanTest *newbtest;
3707 : Node *arg;
3708 :
3709 1132 : arg = eval_const_expressions_mutator((Node *) btest->arg,
3710 : context);
3711 1132 : if (arg && IsA(arg, Const))
3712 : {
3713 : /*
3714 : * If arg is Const, simplify to constant.
3715 : */
3716 111 : Const *carg = (Const *) arg;
3717 : bool result;
3718 :
3719 111 : switch (btest->booltesttype)
3720 : {
3721 0 : case IS_TRUE:
3722 0 : result = (!carg->constisnull &&
3723 0 : DatumGetBool(carg->constvalue));
3724 0 : break;
3725 111 : case IS_NOT_TRUE:
3726 222 : result = (carg->constisnull ||
3727 111 : !DatumGetBool(carg->constvalue));
3728 111 : break;
3729 0 : case IS_FALSE:
3730 0 : result = (!carg->constisnull &&
3731 0 : !DatumGetBool(carg->constvalue));
3732 0 : break;
3733 0 : case IS_NOT_FALSE:
3734 0 : result = (carg->constisnull ||
3735 0 : DatumGetBool(carg->constvalue));
3736 0 : break;
3737 0 : case IS_UNKNOWN:
3738 0 : result = carg->constisnull;
3739 0 : break;
3740 0 : case IS_NOT_UNKNOWN:
3741 0 : result = !carg->constisnull;
3742 0 : break;
3743 0 : default:
3744 0 : elog(ERROR, "unrecognized booltesttype: %d",
3745 : (int) btest->booltesttype);
3746 : result = false; /* keep compiler quiet */
3747 : break;
3748 : }
3749 :
3750 111 : return makeBoolConst(result, false);
3751 : }
3752 1021 : if (arg && expr_is_nonnullable(context->root, (Expr *) arg, false))
3753 : {
3754 : /*
3755 : * If arg is proven non-nullable, simplify to boolean
3756 : * expression or constant.
3757 : */
3758 38 : switch (btest->booltesttype)
3759 : {
3760 12 : case IS_TRUE:
3761 : case IS_NOT_FALSE:
3762 12 : return arg;
3763 :
3764 14 : case IS_FALSE:
3765 : case IS_NOT_TRUE:
3766 14 : return (Node *) make_notclause((Expr *) arg);
3767 :
3768 6 : case IS_UNKNOWN:
3769 6 : return makeBoolConst(false, false);
3770 :
3771 6 : case IS_NOT_UNKNOWN:
3772 6 : return makeBoolConst(true, false);
3773 :
3774 0 : default:
3775 0 : elog(ERROR, "unrecognized booltesttype: %d",
3776 : (int) btest->booltesttype);
3777 : break;
3778 : }
3779 : }
3780 :
3781 983 : newbtest = makeNode(BooleanTest);
3782 983 : newbtest->arg = (Expr *) arg;
3783 983 : newbtest->booltesttype = btest->booltesttype;
3784 983 : newbtest->location = btest->location;
3785 983 : return (Node *) newbtest;
3786 : }
3787 14020 : case T_CoerceToDomain:
3788 : {
3789 : /*
3790 : * If the domain currently has no constraints, we replace the
3791 : * CoerceToDomain node with a simple RelabelType, which is
3792 : * both far faster to execute and more amenable to later
3793 : * optimization. We must then mark the plan as needing to be
3794 : * rebuilt if the domain's constraints change.
3795 : *
3796 : * Also, in estimation mode, always replace CoerceToDomain
3797 : * nodes, effectively assuming that the coercion will succeed.
3798 : */
3799 14020 : CoerceToDomain *cdomain = (CoerceToDomain *) node;
3800 : CoerceToDomain *newcdomain;
3801 : Node *arg;
3802 :
3803 14020 : arg = eval_const_expressions_mutator((Node *) cdomain->arg,
3804 : context);
3805 14005 : if (context->estimate ||
3806 13981 : !DomainHasConstraints(cdomain->resulttype))
3807 : {
3808 : /* Record dependency, if this isn't estimation mode */
3809 9326 : if (context->root && !context->estimate)
3810 9269 : record_plan_type_dependency(context->root,
3811 : cdomain->resulttype);
3812 :
3813 : /* Generate RelabelType to substitute for CoerceToDomain */
3814 9326 : return applyRelabelType(arg,
3815 : cdomain->resulttype,
3816 : cdomain->resulttypmod,
3817 : cdomain->resultcollid,
3818 : cdomain->coercionformat,
3819 : cdomain->location,
3820 : true);
3821 : }
3822 :
3823 4679 : newcdomain = makeNode(CoerceToDomain);
3824 4679 : newcdomain->arg = (Expr *) arg;
3825 4679 : newcdomain->resulttype = cdomain->resulttype;
3826 4679 : newcdomain->resulttypmod = cdomain->resulttypmod;
3827 4679 : newcdomain->resultcollid = cdomain->resultcollid;
3828 4679 : newcdomain->coercionformat = cdomain->coercionformat;
3829 4679 : newcdomain->location = cdomain->location;
3830 4679 : return (Node *) newcdomain;
3831 : }
3832 2213 : case T_PlaceHolderVar:
3833 :
3834 : /*
3835 : * In estimation mode, just strip the PlaceHolderVar node
3836 : * altogether; this amounts to estimating that the contained value
3837 : * won't be forced to null by an outer join. In regular mode we
3838 : * just use the default behavior (ie, simplify the expression but
3839 : * leave the PlaceHolderVar node intact).
3840 : */
3841 2213 : if (context->estimate)
3842 : {
3843 420 : PlaceHolderVar *phv = (PlaceHolderVar *) node;
3844 :
3845 420 : return eval_const_expressions_mutator((Node *) phv->phexpr,
3846 : context);
3847 : }
3848 1793 : break;
3849 45 : case T_ConvertRowtypeExpr:
3850 : {
3851 45 : ConvertRowtypeExpr *cre = castNode(ConvertRowtypeExpr, node);
3852 : Node *arg;
3853 : ConvertRowtypeExpr *newcre;
3854 :
3855 45 : arg = eval_const_expressions_mutator((Node *) cre->arg,
3856 : context);
3857 :
3858 45 : newcre = makeNode(ConvertRowtypeExpr);
3859 45 : newcre->resulttype = cre->resulttype;
3860 45 : newcre->convertformat = cre->convertformat;
3861 45 : newcre->location = cre->location;
3862 :
3863 : /*
3864 : * In case of a nested ConvertRowtypeExpr, we can convert the
3865 : * leaf row directly to the topmost row format without any
3866 : * intermediate conversions. (This works because
3867 : * ConvertRowtypeExpr is used only for child->parent
3868 : * conversion in inheritance trees, which works by exact match
3869 : * of column name, and a column absent in an intermediate
3870 : * result can't be present in the final result.)
3871 : *
3872 : * No need to check more than one level deep, because the
3873 : * above recursion will have flattened anything else.
3874 : */
3875 45 : if (arg != NULL && IsA(arg, ConvertRowtypeExpr))
3876 : {
3877 6 : ConvertRowtypeExpr *argcre = (ConvertRowtypeExpr *) arg;
3878 :
3879 6 : arg = (Node *) argcre->arg;
3880 :
3881 : /*
3882 : * Make sure an outer implicit conversion can't hide an
3883 : * inner explicit one.
3884 : */
3885 6 : if (newcre->convertformat == COERCE_IMPLICIT_CAST)
3886 0 : newcre->convertformat = argcre->convertformat;
3887 : }
3888 :
3889 45 : newcre->arg = (Expr *) arg;
3890 :
3891 45 : if (arg != NULL && IsA(arg, Const))
3892 9 : return ece_evaluate_expr((Node *) newcre);
3893 36 : return (Node *) newcre;
3894 : }
3895 3743653 : default:
3896 3743653 : break;
3897 : }
3898 :
3899 : /*
3900 : * For any node type not handled above, copy the node unchanged but
3901 : * const-simplify its subexpressions. This is the correct thing for node
3902 : * types whose behavior might change between planning and execution, such
3903 : * as CurrentOfExpr. It's also a safe default for new node types not
3904 : * known to this routine.
3905 : */
3906 3745446 : return ece_generic_processing(node);
3907 : }
3908 :
3909 : /*
3910 : * Subroutine for eval_const_expressions: check for non-Const nodes.
3911 : *
3912 : * We can abort recursion immediately on finding a non-Const node. This is
3913 : * critical for performance, else eval_const_expressions_mutator would take
3914 : * O(N^2) time on non-simplifiable trees. However, we do need to descend
3915 : * into List nodes since expression_tree_walker sometimes invokes the walker
3916 : * function directly on List subtrees.
3917 : */
3918 : static bool
3919 114848 : contain_non_const_walker(Node *node, void *context)
3920 : {
3921 114848 : if (node == NULL)
3922 362 : return false;
3923 114486 : if (IsA(node, Const))
3924 58236 : return false;
3925 56250 : if (IsA(node, List))
3926 18815 : return expression_tree_walker(node, contain_non_const_walker, context);
3927 : /* Otherwise, abort the tree traversal and return true */
3928 37435 : return true;
3929 : }
3930 :
3931 : /*
3932 : * Subroutine for eval_const_expressions: check if a function is OK to evaluate
3933 : */
3934 : static bool
3935 188 : ece_function_is_safe(Oid funcid, eval_const_expressions_context *context)
3936 : {
3937 188 : char provolatile = func_volatile(funcid);
3938 :
3939 : /*
3940 : * Ordinarily we are only allowed to simplify immutable functions. But for
3941 : * purposes of estimation, we consider it okay to simplify functions that
3942 : * are merely stable; the risk that the result might change from planning
3943 : * time to execution time is worth taking in preference to not being able
3944 : * to estimate the value at all.
3945 : */
3946 188 : if (provolatile == PROVOLATILE_IMMUTABLE)
3947 188 : return true;
3948 0 : if (context->estimate && provolatile == PROVOLATILE_STABLE)
3949 0 : return true;
3950 0 : return false;
3951 : }
3952 :
3953 : /*
3954 : * Subroutine for eval_const_expressions: process arguments of an OR clause
3955 : *
3956 : * This includes flattening of nested ORs as well as recursion to
3957 : * eval_const_expressions to simplify the OR arguments.
3958 : *
3959 : * After simplification, OR arguments are handled as follows:
3960 : * non constant: keep
3961 : * FALSE: drop (does not affect result)
3962 : * TRUE: force result to TRUE
3963 : * NULL: keep only one
3964 : * We must keep one NULL input because OR expressions evaluate to NULL when no
3965 : * input is TRUE and at least one is NULL. We don't actually include the NULL
3966 : * here, that's supposed to be done by the caller.
3967 : *
3968 : * The output arguments *haveNull and *forceTrue must be initialized false
3969 : * by the caller. They will be set true if a NULL constant or TRUE constant,
3970 : * respectively, is detected anywhere in the argument list.
3971 : */
3972 : static List *
3973 10446 : simplify_or_arguments(List *args,
3974 : eval_const_expressions_context *context,
3975 : bool *haveNull, bool *forceTrue)
3976 : {
3977 10446 : List *newargs = NIL;
3978 : List *unprocessed_args;
3979 :
3980 : /*
3981 : * We want to ensure that any OR immediately beneath another OR gets
3982 : * flattened into a single OR-list, so as to simplify later reasoning.
3983 : *
3984 : * To avoid stack overflow from recursion of eval_const_expressions, we
3985 : * resort to some tenseness here: we keep a list of not-yet-processed
3986 : * inputs, and handle flattening of nested ORs by prepending to the to-do
3987 : * list instead of recursing. Now that the parser generates N-argument
3988 : * ORs from simple lists, this complexity is probably less necessary than
3989 : * it once was, but we might as well keep the logic.
3990 : */
3991 10446 : unprocessed_args = list_copy(args);
3992 33889 : while (unprocessed_args)
3993 : {
3994 23529 : Node *arg = (Node *) linitial(unprocessed_args);
3995 :
3996 23529 : unprocessed_args = list_delete_first(unprocessed_args);
3997 :
3998 : /* flatten nested ORs as per above comment */
3999 23529 : if (is_orclause(arg))
4000 5 : {
4001 5 : List *subargs = ((BoolExpr *) arg)->args;
4002 5 : List *oldlist = unprocessed_args;
4003 :
4004 5 : unprocessed_args = list_concat_copy(subargs, unprocessed_args);
4005 : /* perhaps-overly-tense code to avoid leaking old lists */
4006 5 : list_free(oldlist);
4007 5 : continue;
4008 : }
4009 :
4010 : /* If it's not an OR, simplify it */
4011 23524 : arg = eval_const_expressions_mutator(arg, context);
4012 :
4013 : /*
4014 : * It is unlikely but not impossible for simplification of a non-OR
4015 : * clause to produce an OR. Recheck, but don't be too tense about it
4016 : * since it's not a mainstream case. In particular we don't worry
4017 : * about const-simplifying the input twice, nor about list leakage.
4018 : */
4019 23524 : if (is_orclause(arg))
4020 0 : {
4021 0 : List *subargs = ((BoolExpr *) arg)->args;
4022 :
4023 0 : unprocessed_args = list_concat_copy(subargs, unprocessed_args);
4024 0 : continue;
4025 : }
4026 :
4027 : /*
4028 : * OK, we have a const-simplified non-OR argument. Process it per
4029 : * comments above.
4030 : */
4031 23524 : if (IsA(arg, Const))
4032 2408 : {
4033 2494 : Const *const_input = (Const *) arg;
4034 :
4035 2494 : if (const_input->constisnull)
4036 2304 : *haveNull = true;
4037 190 : else if (DatumGetBool(const_input->constvalue))
4038 : {
4039 86 : *forceTrue = true;
4040 :
4041 : /*
4042 : * Once we detect a TRUE result we can just exit the loop
4043 : * immediately. However, if we ever add a notion of
4044 : * non-removable functions, we'd need to keep scanning.
4045 : */
4046 86 : return NIL;
4047 : }
4048 : /* otherwise, we can drop the constant-false input */
4049 2408 : continue;
4050 : }
4051 :
4052 : /* else emit the simplified arg into the result list */
4053 21030 : newargs = lappend(newargs, arg);
4054 : }
4055 :
4056 10360 : return newargs;
4057 : }
4058 :
4059 : /*
4060 : * Subroutine for eval_const_expressions: process arguments of an AND clause
4061 : *
4062 : * This includes flattening of nested ANDs as well as recursion to
4063 : * eval_const_expressions to simplify the AND arguments.
4064 : *
4065 : * After simplification, AND arguments are handled as follows:
4066 : * non constant: keep
4067 : * TRUE: drop (does not affect result)
4068 : * FALSE: force result to FALSE
4069 : * NULL: keep only one
4070 : * We must keep one NULL input because AND expressions evaluate to NULL when
4071 : * no input is FALSE and at least one is NULL. We don't actually include the
4072 : * NULL here, that's supposed to be done by the caller.
4073 : *
4074 : * The output arguments *haveNull and *forceFalse must be initialized false
4075 : * by the caller. They will be set true if a null constant or false constant,
4076 : * respectively, is detected anywhere in the argument list.
4077 : */
4078 : static List *
4079 83378 : simplify_and_arguments(List *args,
4080 : eval_const_expressions_context *context,
4081 : bool *haveNull, bool *forceFalse)
4082 : {
4083 83378 : List *newargs = NIL;
4084 : List *unprocessed_args;
4085 :
4086 : /* See comments in simplify_or_arguments */
4087 83378 : unprocessed_args = list_copy(args);
4088 303704 : while (unprocessed_args)
4089 : {
4090 221113 : Node *arg = (Node *) linitial(unprocessed_args);
4091 :
4092 221113 : unprocessed_args = list_delete_first(unprocessed_args);
4093 :
4094 : /* flatten nested ANDs as per above comment */
4095 221113 : if (is_andclause(arg))
4096 2025 : {
4097 2025 : List *subargs = ((BoolExpr *) arg)->args;
4098 2025 : List *oldlist = unprocessed_args;
4099 :
4100 2025 : unprocessed_args = list_concat_copy(subargs, unprocessed_args);
4101 : /* perhaps-overly-tense code to avoid leaking old lists */
4102 2025 : list_free(oldlist);
4103 2025 : continue;
4104 : }
4105 :
4106 : /* If it's not an AND, simplify it */
4107 219088 : arg = eval_const_expressions_mutator(arg, context);
4108 :
4109 : /*
4110 : * It is unlikely but not impossible for simplification of a non-AND
4111 : * clause to produce an AND. Recheck, but don't be too tense about it
4112 : * since it's not a mainstream case. In particular we don't worry
4113 : * about const-simplifying the input twice, nor about list leakage.
4114 : */
4115 219088 : if (is_andclause(arg))
4116 18 : {
4117 18 : List *subargs = ((BoolExpr *) arg)->args;
4118 :
4119 18 : unprocessed_args = list_concat_copy(subargs, unprocessed_args);
4120 18 : continue;
4121 : }
4122 :
4123 : /*
4124 : * OK, we have a const-simplified non-AND argument. Process it per
4125 : * comments above.
4126 : */
4127 219070 : if (IsA(arg, Const))
4128 1065 : {
4129 1852 : Const *const_input = (Const *) arg;
4130 :
4131 1852 : if (const_input->constisnull)
4132 9 : *haveNull = true;
4133 1843 : else if (!DatumGetBool(const_input->constvalue))
4134 : {
4135 787 : *forceFalse = true;
4136 :
4137 : /*
4138 : * Once we detect a FALSE result we can just exit the loop
4139 : * immediately. However, if we ever add a notion of
4140 : * non-removable functions, we'd need to keep scanning.
4141 : */
4142 787 : return NIL;
4143 : }
4144 : /* otherwise, we can drop the constant-true input */
4145 1065 : continue;
4146 : }
4147 :
4148 : /* else emit the simplified arg into the result list */
4149 217218 : newargs = lappend(newargs, arg);
4150 : }
4151 :
4152 82591 : return newargs;
4153 : }
4154 :
4155 : /*
4156 : * Subroutine for eval_const_expressions: try to simplify boolean equality
4157 : * or inequality condition
4158 : *
4159 : * Inputs are the operator OID and the simplified arguments to the operator.
4160 : * Returns a simplified expression if successful, or NULL if cannot
4161 : * simplify the expression.
4162 : *
4163 : * The idea here is to reduce "x = true" to "x" and "x = false" to "NOT x",
4164 : * or similarly "x <> true" to "NOT x" and "x <> false" to "x".
4165 : * This is only marginally useful in itself, but doing it in constant folding
4166 : * ensures that we will recognize these forms as being equivalent in, for
4167 : * example, partial index matching.
4168 : *
4169 : * We come here only if simplify_function has failed; therefore we cannot
4170 : * see two constant inputs, nor a constant-NULL input.
4171 : */
4172 : static Node *
4173 1366 : simplify_boolean_equality(Oid opno, List *args)
4174 : {
4175 : Node *leftop;
4176 : Node *rightop;
4177 :
4178 : Assert(list_length(args) == 2);
4179 1366 : leftop = linitial(args);
4180 1366 : rightop = lsecond(args);
4181 1366 : if (leftop && IsA(leftop, Const))
4182 : {
4183 : Assert(!((Const *) leftop)->constisnull);
4184 0 : if (opno == BooleanEqualOperator)
4185 : {
4186 0 : if (DatumGetBool(((Const *) leftop)->constvalue))
4187 0 : return rightop; /* true = foo */
4188 : else
4189 0 : return negate_clause(rightop); /* false = foo */
4190 : }
4191 : else
4192 : {
4193 0 : if (DatumGetBool(((Const *) leftop)->constvalue))
4194 0 : return negate_clause(rightop); /* true <> foo */
4195 : else
4196 0 : return rightop; /* false <> foo */
4197 : }
4198 : }
4199 1366 : if (rightop && IsA(rightop, Const))
4200 : {
4201 : Assert(!((Const *) rightop)->constisnull);
4202 958 : if (opno == BooleanEqualOperator)
4203 : {
4204 925 : if (DatumGetBool(((Const *) rightop)->constvalue))
4205 127 : return leftop; /* foo = true */
4206 : else
4207 798 : return negate_clause(leftop); /* foo = false */
4208 : }
4209 : else
4210 : {
4211 33 : if (DatumGetBool(((Const *) rightop)->constvalue))
4212 30 : return negate_clause(leftop); /* foo <> true */
4213 : else
4214 3 : return leftop; /* foo <> false */
4215 : }
4216 : }
4217 408 : return NULL;
4218 : }
4219 :
4220 : /*
4221 : * Subroutine for eval_const_expressions: try to simplify a function call
4222 : * (which might originally have been an operator; we don't care)
4223 : *
4224 : * Inputs are the function OID, actual result type OID (which is needed for
4225 : * polymorphic functions), result typmod, result collation, the input
4226 : * collation to use for the function, the original argument list (not
4227 : * const-simplified yet, unless process_args is false), and some flags;
4228 : * also the context data for eval_const_expressions.
4229 : *
4230 : * Returns a simplified expression if successful, or NULL if cannot
4231 : * simplify the function call.
4232 : *
4233 : * This function is also responsible for converting named-notation argument
4234 : * lists into positional notation and/or adding any needed default argument
4235 : * expressions; which is a bit grotty, but it avoids extra fetches of the
4236 : * function's pg_proc tuple. For this reason, the args list is
4237 : * pass-by-reference. Conversion and const-simplification of the args list
4238 : * will be done even if simplification of the function call itself is not
4239 : * possible.
4240 : */
4241 : static Expr *
4242 700392 : simplify_function(Oid funcid, Oid result_type, int32 result_typmod,
4243 : Oid result_collid, Oid input_collid, List **args_p,
4244 : bool funcvariadic, bool process_args, bool allow_non_const,
4245 : eval_const_expressions_context *context)
4246 : {
4247 700392 : List *args = *args_p;
4248 : HeapTuple func_tuple;
4249 : Form_pg_proc func_form;
4250 : Expr *newexpr;
4251 :
4252 : /*
4253 : * We have three strategies for simplification: execute the function to
4254 : * deliver a constant result, use a transform function to generate a
4255 : * substitute node tree, or expand in-line the body of the function
4256 : * definition (which only works for simple SQL-language functions, but
4257 : * that is a common case). Each case needs access to the function's
4258 : * pg_proc tuple, so fetch it just once.
4259 : *
4260 : * Note: the allow_non_const flag suppresses both the second and third
4261 : * strategies; so if !allow_non_const, simplify_function can only return a
4262 : * Const or NULL. Argument-list rewriting happens anyway, though.
4263 : */
4264 700392 : func_tuple = SearchSysCache1(PROCOID, ObjectIdGetDatum(funcid));
4265 700392 : if (!HeapTupleIsValid(func_tuple))
4266 0 : elog(ERROR, "cache lookup failed for function %u", funcid);
4267 700392 : func_form = (Form_pg_proc) GETSTRUCT(func_tuple);
4268 :
4269 : /*
4270 : * Process the function arguments, unless the caller did it already.
4271 : *
4272 : * Here we must deal with named or defaulted arguments, and then
4273 : * recursively apply eval_const_expressions to the whole argument list.
4274 : */
4275 700392 : if (process_args)
4276 : {
4277 699131 : args = expand_function_arguments(args, false, result_type, func_tuple);
4278 699131 : args = (List *) expression_tree_mutator((Node *) args,
4279 : eval_const_expressions_mutator,
4280 : context);
4281 : /* Argument processing done, give it back to the caller */
4282 699068 : *args_p = args;
4283 : }
4284 :
4285 : /* Now attempt simplification of the function call proper. */
4286 :
4287 700329 : newexpr = evaluate_function(funcid, result_type, result_typmod,
4288 : result_collid, input_collid,
4289 : args, funcvariadic,
4290 : func_tuple, context);
4291 :
4292 698354 : if (!newexpr && allow_non_const && OidIsValid(func_form->prosupport))
4293 : {
4294 : /*
4295 : * Build a SupportRequestSimplify node to pass to the support
4296 : * function, pointing to a dummy FuncExpr node containing the
4297 : * simplified arg list. We use this approach to present a uniform
4298 : * interface to the support function regardless of how the target
4299 : * function is actually being invoked.
4300 : */
4301 : SupportRequestSimplify req;
4302 : FuncExpr fexpr;
4303 :
4304 18458 : fexpr.xpr.type = T_FuncExpr;
4305 18458 : fexpr.funcid = funcid;
4306 18458 : fexpr.funcresulttype = result_type;
4307 18458 : fexpr.funcretset = func_form->proretset;
4308 18458 : fexpr.funcvariadic = funcvariadic;
4309 18458 : fexpr.funcformat = COERCE_EXPLICIT_CALL;
4310 18458 : fexpr.funccollid = result_collid;
4311 18458 : fexpr.inputcollid = input_collid;
4312 18458 : fexpr.args = args;
4313 18458 : fexpr.location = -1;
4314 :
4315 18458 : req.type = T_SupportRequestSimplify;
4316 18458 : req.root = context->root;
4317 18458 : req.fcall = &fexpr;
4318 :
4319 : newexpr = (Expr *)
4320 18458 : DatumGetPointer(OidFunctionCall1(func_form->prosupport,
4321 : PointerGetDatum(&req)));
4322 :
4323 : /* catch a possible API misunderstanding */
4324 : Assert(newexpr != (Expr *) &fexpr);
4325 : }
4326 :
4327 698354 : if (!newexpr && allow_non_const)
4328 600466 : newexpr = inline_function(funcid, result_type, result_collid,
4329 : input_collid, args, funcvariadic,
4330 : func_tuple, context);
4331 :
4332 698347 : ReleaseSysCache(func_tuple);
4333 :
4334 698347 : return newexpr;
4335 : }
4336 :
4337 : /*
4338 : * simplify_aggref
4339 : * Call the Aggref.aggfnoid's prosupport function to allow it to
4340 : * determine if simplification of the Aggref is possible. Returns the
4341 : * newly simplified node if conversion took place; otherwise, returns the
4342 : * original Aggref.
4343 : *
4344 : * See SupportRequestSimplifyAggref comments in supportnodes.h for further
4345 : * details.
4346 : */
4347 : static Node *
4348 26320 : simplify_aggref(Aggref *aggref, eval_const_expressions_context *context)
4349 : {
4350 26320 : Oid prosupport = get_func_support(aggref->aggfnoid);
4351 :
4352 26320 : if (OidIsValid(prosupport))
4353 : {
4354 : SupportRequestSimplifyAggref req;
4355 : Node *newnode;
4356 :
4357 : /*
4358 : * Build a SupportRequestSimplifyAggref node to pass to the support
4359 : * function.
4360 : */
4361 10343 : req.type = T_SupportRequestSimplifyAggref;
4362 10343 : req.root = context->root;
4363 10343 : req.aggref = aggref;
4364 :
4365 10343 : newnode = (Node *) DatumGetPointer(OidFunctionCall1(prosupport,
4366 : PointerGetDatum(&req)));
4367 :
4368 : /*
4369 : * We expect the support function to return either a new Node or NULL
4370 : * (when simplification isn't possible).
4371 : */
4372 : Assert(newnode != (Node *) aggref || newnode == NULL);
4373 :
4374 10343 : if (newnode != NULL)
4375 293 : return newnode;
4376 : }
4377 :
4378 26027 : return (Node *) aggref;
4379 : }
4380 :
4381 : /*
4382 : * var_is_nonnullable: check to see if the Var cannot be NULL
4383 : *
4384 : * If the Var is defined NOT NULL and meanwhile is not nulled by any outer
4385 : * joins or grouping sets, then we can know that it cannot be NULL.
4386 : *
4387 : * use_rel_info indicates whether the corresponding RelOptInfo is available for
4388 : * use.
4389 : */
4390 : bool
4391 17407 : var_is_nonnullable(PlannerInfo *root, Var *var, bool use_rel_info)
4392 : {
4393 17407 : Bitmapset *notnullattnums = NULL;
4394 :
4395 : Assert(IsA(var, Var));
4396 :
4397 : /* skip upper-level Vars */
4398 17407 : if (var->varlevelsup != 0)
4399 27 : return false;
4400 :
4401 : /* could the Var be nulled by any outer joins or grouping sets? */
4402 17380 : if (!bms_is_empty(var->varnullingrels))
4403 2391 : return false;
4404 :
4405 : /* system columns cannot be NULL */
4406 14989 : if (var->varattno < 0)
4407 18 : return true;
4408 :
4409 : /*
4410 : * Check if the Var is defined as NOT NULL. We retrieve the column NOT
4411 : * NULL constraint information from the corresponding RelOptInfo if it is
4412 : * available; otherwise, we search the hash table for this information.
4413 : */
4414 14971 : if (use_rel_info)
4415 : {
4416 4456 : RelOptInfo *rel = find_base_rel(root, var->varno);
4417 :
4418 4456 : notnullattnums = rel->notnullattnums;
4419 : }
4420 : else
4421 : {
4422 10515 : RangeTblEntry *rte = planner_rt_fetch(var->varno, root);
4423 :
4424 : /*
4425 : * We must skip inheritance parent tables, as some child tables may
4426 : * have a NOT NULL constraint for a column while others may not. This
4427 : * cannot happen with partitioned tables, though.
4428 : */
4429 10515 : if (rte->inh && rte->relkind != RELKIND_PARTITIONED_TABLE)
4430 139 : return false;
4431 :
4432 10376 : notnullattnums = find_relation_notnullatts(root, rte->relid);
4433 : }
4434 :
4435 29634 : if (var->varattno > 0 &&
4436 14802 : bms_is_member(var->varattno, notnullattnums))
4437 676 : return true;
4438 :
4439 14156 : return false;
4440 : }
4441 :
4442 : /*
4443 : * expr_is_nonnullable: check to see if the Expr cannot be NULL
4444 : *
4445 : * Returns true iff the given 'expr' cannot produce SQL NULLs.
4446 : *
4447 : * If 'use_rel_info' is true, nullability of Vars is checked via the
4448 : * corresponding RelOptInfo for the given Var. Some callers require
4449 : * nullability information before RelOptInfos are generated. These should
4450 : * pass 'use_rel_info' as false.
4451 : *
4452 : * For now, we support only a limited set of expression types. Support for
4453 : * additional node types can be added in the future.
4454 : */
4455 : bool
4456 29266 : expr_is_nonnullable(PlannerInfo *root, Expr *expr, bool use_rel_info)
4457 : {
4458 : /* since this function recurses, it could be driven to stack overflow */
4459 29266 : check_stack_depth();
4460 :
4461 29266 : switch (nodeTag(expr))
4462 : {
4463 25884 : case T_Var:
4464 : {
4465 25884 : if (root)
4466 17407 : return var_is_nonnullable(root, (Var *) expr, use_rel_info);
4467 : }
4468 8477 : break;
4469 352 : case T_Const:
4470 352 : return !((Const *) expr)->constisnull;
4471 93 : case T_CoalesceExpr:
4472 : {
4473 : /*
4474 : * A CoalesceExpr returns NULL if and only if all its
4475 : * arguments are NULL. Therefore, we can determine that a
4476 : * CoalesceExpr cannot be NULL if at least one of its
4477 : * arguments can be proven non-nullable.
4478 : */
4479 93 : CoalesceExpr *coalesceexpr = (CoalesceExpr *) expr;
4480 :
4481 330 : foreach_ptr(Expr, arg, coalesceexpr->args)
4482 : {
4483 186 : if (expr_is_nonnullable(root, arg, use_rel_info))
4484 21 : return true;
4485 : }
4486 : }
4487 72 : break;
4488 9 : case T_MinMaxExpr:
4489 : {
4490 : /*
4491 : * Like CoalesceExpr, a MinMaxExpr returns NULL only if all
4492 : * its arguments evaluate to NULL.
4493 : */
4494 9 : MinMaxExpr *minmaxexpr = (MinMaxExpr *) expr;
4495 :
4496 30 : foreach_ptr(Expr, arg, minmaxexpr->args)
4497 : {
4498 18 : if (expr_is_nonnullable(root, arg, use_rel_info))
4499 3 : return true;
4500 : }
4501 : }
4502 6 : break;
4503 54 : case T_CaseExpr:
4504 : {
4505 : /*
4506 : * A CASE expression is non-nullable if all branch results are
4507 : * non-nullable. We must also verify that the default result
4508 : * (ELSE) exists and is non-nullable.
4509 : */
4510 54 : CaseExpr *caseexpr = (CaseExpr *) expr;
4511 :
4512 : /* The default result must be present and non-nullable */
4513 54 : if (caseexpr->defresult == NULL ||
4514 54 : !expr_is_nonnullable(root, caseexpr->defresult, use_rel_info))
4515 45 : return false;
4516 :
4517 : /* All branch results must be non-nullable */
4518 15 : foreach_ptr(CaseWhen, casewhen, caseexpr->args)
4519 : {
4520 9 : if (!expr_is_nonnullable(root, casewhen->result, use_rel_info))
4521 6 : return false;
4522 : }
4523 :
4524 3 : return true;
4525 : }
4526 : break;
4527 3 : case T_ArrayExpr:
4528 : {
4529 : /*
4530 : * An ARRAY[] expression always returns a valid Array object,
4531 : * even if it is empty (ARRAY[]) or contains NULLs
4532 : * (ARRAY[NULL]). It never evaluates to a SQL NULL.
4533 : */
4534 3 : return true;
4535 : }
4536 5 : case T_NullTest:
4537 : {
4538 : /*
4539 : * An IS NULL / IS NOT NULL expression always returns a
4540 : * boolean value. It never returns SQL NULL.
4541 : */
4542 5 : return true;
4543 : }
4544 3 : case T_BooleanTest:
4545 : {
4546 : /*
4547 : * A BooleanTest expression always evaluates to a boolean
4548 : * value. It never returns SQL NULL.
4549 : */
4550 3 : return true;
4551 : }
4552 3 : case T_DistinctExpr:
4553 : {
4554 : /*
4555 : * IS DISTINCT FROM never returns NULL, effectively acting as
4556 : * though NULL were a normal data value.
4557 : */
4558 3 : return true;
4559 : }
4560 35 : case T_RelabelType:
4561 : {
4562 : /*
4563 : * RelabelType does not change the nullability of the data.
4564 : * The result is non-nullable if and only if the argument is
4565 : * non-nullable.
4566 : */
4567 35 : return expr_is_nonnullable(root, ((RelabelType *) expr)->arg,
4568 : use_rel_info);
4569 : }
4570 2825 : default:
4571 2825 : break;
4572 : }
4573 :
4574 11380 : return false;
4575 : }
4576 :
4577 : /*
4578 : * expand_function_arguments: convert named-notation args to positional args
4579 : * and/or insert default args, as needed
4580 : *
4581 : * Returns a possibly-transformed version of the args list.
4582 : *
4583 : * If include_out_arguments is true, then the args list and the result
4584 : * include OUT arguments.
4585 : *
4586 : * The expected result type of the call must be given, for sanity-checking
4587 : * purposes. Also, we ask the caller to provide the function's actual
4588 : * pg_proc tuple, not just its OID.
4589 : *
4590 : * If we need to change anything, the input argument list is copied, not
4591 : * modified.
4592 : *
4593 : * Note: this gets applied to operator argument lists too, even though the
4594 : * cases it handles should never occur there. This should be OK since it
4595 : * will fall through very quickly if there's nothing to do.
4596 : */
4597 : List *
4598 701234 : expand_function_arguments(List *args, bool include_out_arguments,
4599 : Oid result_type, HeapTuple func_tuple)
4600 : {
4601 701234 : Form_pg_proc funcform = (Form_pg_proc) GETSTRUCT(func_tuple);
4602 701234 : Oid *proargtypes = funcform->proargtypes.values;
4603 701234 : int pronargs = funcform->pronargs;
4604 701234 : bool has_named_args = false;
4605 : ListCell *lc;
4606 :
4607 : /*
4608 : * If we are asked to match to OUT arguments, then use the proallargtypes
4609 : * array (which includes those); otherwise use proargtypes (which
4610 : * doesn't). Of course, if proallargtypes is null, we always use
4611 : * proargtypes. (Fetching proallargtypes is annoyingly expensive
4612 : * considering that we may have nothing to do here, but fortunately the
4613 : * common case is include_out_arguments == false.)
4614 : */
4615 701234 : if (include_out_arguments)
4616 : {
4617 : Datum proallargtypes;
4618 : bool isNull;
4619 :
4620 249 : proallargtypes = SysCacheGetAttr(PROCOID, func_tuple,
4621 : Anum_pg_proc_proallargtypes,
4622 : &isNull);
4623 249 : if (!isNull)
4624 : {
4625 101 : ArrayType *arr = DatumGetArrayTypeP(proallargtypes);
4626 :
4627 101 : pronargs = ARR_DIMS(arr)[0];
4628 101 : if (ARR_NDIM(arr) != 1 ||
4629 101 : pronargs < 0 ||
4630 101 : ARR_HASNULL(arr) ||
4631 101 : ARR_ELEMTYPE(arr) != OIDOID)
4632 0 : elog(ERROR, "proallargtypes is not a 1-D Oid array or it contains nulls");
4633 : Assert(pronargs >= funcform->pronargs);
4634 101 : proargtypes = (Oid *) ARR_DATA_PTR(arr);
4635 : }
4636 : }
4637 :
4638 : /* Do we have any named arguments? */
4639 1911836 : foreach(lc, args)
4640 : {
4641 1218992 : Node *arg = (Node *) lfirst(lc);
4642 :
4643 1218992 : if (IsA(arg, NamedArgExpr))
4644 : {
4645 8390 : has_named_args = true;
4646 8390 : break;
4647 : }
4648 : }
4649 :
4650 : /* If so, we must apply reorder_function_arguments */
4651 701234 : if (has_named_args)
4652 : {
4653 8390 : args = reorder_function_arguments(args, pronargs, func_tuple);
4654 : /* Recheck argument types and add casts if needed */
4655 8390 : recheck_cast_function_args(args, result_type,
4656 : proargtypes, pronargs,
4657 : func_tuple);
4658 : }
4659 692844 : else if (list_length(args) < pronargs)
4660 : {
4661 : /* No named args, but we seem to be short some defaults */
4662 3384 : args = add_function_defaults(args, pronargs, func_tuple);
4663 : /* Recheck argument types and add casts if needed */
4664 3384 : recheck_cast_function_args(args, result_type,
4665 : proargtypes, pronargs,
4666 : func_tuple);
4667 : }
4668 :
4669 701234 : return args;
4670 : }
4671 :
4672 : /*
4673 : * reorder_function_arguments: convert named-notation args to positional args
4674 : *
4675 : * This function also inserts default argument values as needed, since it's
4676 : * impossible to form a truly valid positional call without that.
4677 : */
4678 : static List *
4679 8390 : reorder_function_arguments(List *args, int pronargs, HeapTuple func_tuple)
4680 : {
4681 8390 : Form_pg_proc funcform = (Form_pg_proc) GETSTRUCT(func_tuple);
4682 8390 : int nargsprovided = list_length(args);
4683 : Node *argarray[FUNC_MAX_ARGS];
4684 : ListCell *lc;
4685 : int i;
4686 :
4687 : Assert(nargsprovided <= pronargs);
4688 8390 : if (pronargs < 0 || pronargs > FUNC_MAX_ARGS)
4689 0 : elog(ERROR, "too many function arguments");
4690 8390 : memset(argarray, 0, pronargs * sizeof(Node *));
4691 :
4692 : /* Deconstruct the argument list into an array indexed by argnumber */
4693 8390 : i = 0;
4694 34287 : foreach(lc, args)
4695 : {
4696 25897 : Node *arg = (Node *) lfirst(lc);
4697 :
4698 25897 : if (!IsA(arg, NamedArgExpr))
4699 : {
4700 : /* positional argument, assumed to precede all named args */
4701 : Assert(argarray[i] == NULL);
4702 1235 : argarray[i++] = arg;
4703 : }
4704 : else
4705 : {
4706 24662 : NamedArgExpr *na = (NamedArgExpr *) arg;
4707 :
4708 : Assert(na->argnumber >= 0 && na->argnumber < pronargs);
4709 : Assert(argarray[na->argnumber] == NULL);
4710 24662 : argarray[na->argnumber] = (Node *) na->arg;
4711 : }
4712 : }
4713 :
4714 : /*
4715 : * Fetch default expressions, if needed, and insert into array at proper
4716 : * locations (they aren't necessarily consecutive or all used)
4717 : */
4718 8390 : if (nargsprovided < pronargs)
4719 : {
4720 3870 : List *defaults = fetch_function_defaults(func_tuple);
4721 :
4722 3870 : i = pronargs - funcform->pronargdefaults;
4723 22164 : foreach(lc, defaults)
4724 : {
4725 18294 : if (argarray[i] == NULL)
4726 7835 : argarray[i] = (Node *) lfirst(lc);
4727 18294 : i++;
4728 : }
4729 : }
4730 :
4731 : /* Now reconstruct the args list in proper order */
4732 8390 : args = NIL;
4733 42122 : for (i = 0; i < pronargs; i++)
4734 : {
4735 : Assert(argarray[i] != NULL);
4736 33732 : args = lappend(args, argarray[i]);
4737 : }
4738 :
4739 8390 : return args;
4740 : }
4741 :
4742 : /*
4743 : * add_function_defaults: add missing function arguments from its defaults
4744 : *
4745 : * This is used only when the argument list was positional to begin with,
4746 : * and so we know we just need to add defaults at the end.
4747 : */
4748 : static List *
4749 3384 : add_function_defaults(List *args, int pronargs, HeapTuple func_tuple)
4750 : {
4751 3384 : int nargsprovided = list_length(args);
4752 : List *defaults;
4753 : int ndelete;
4754 :
4755 : /* Get all the default expressions from the pg_proc tuple */
4756 3384 : defaults = fetch_function_defaults(func_tuple);
4757 :
4758 : /* Delete any unused defaults from the list */
4759 3384 : ndelete = nargsprovided + list_length(defaults) - pronargs;
4760 3384 : if (ndelete < 0)
4761 0 : elog(ERROR, "not enough default arguments");
4762 3384 : if (ndelete > 0)
4763 123 : defaults = list_delete_first_n(defaults, ndelete);
4764 :
4765 : /* And form the combined argument list, not modifying the input list */
4766 3384 : return list_concat_copy(args, defaults);
4767 : }
4768 :
4769 : /*
4770 : * fetch_function_defaults: get function's default arguments as expression list
4771 : */
4772 : static List *
4773 7254 : fetch_function_defaults(HeapTuple func_tuple)
4774 : {
4775 : List *defaults;
4776 : Datum proargdefaults;
4777 : char *str;
4778 :
4779 7254 : proargdefaults = SysCacheGetAttrNotNull(PROCOID, func_tuple,
4780 : Anum_pg_proc_proargdefaults);
4781 7254 : str = TextDatumGetCString(proargdefaults);
4782 7254 : defaults = castNode(List, stringToNode(str));
4783 7254 : pfree(str);
4784 7254 : return defaults;
4785 : }
4786 :
4787 : /*
4788 : * recheck_cast_function_args: recheck function args and typecast as needed
4789 : * after adding defaults.
4790 : *
4791 : * It is possible for some of the defaulted arguments to be polymorphic;
4792 : * therefore we can't assume that the default expressions have the correct
4793 : * data types already. We have to re-resolve polymorphics and do coercion
4794 : * just like the parser did.
4795 : *
4796 : * This should be a no-op if there are no polymorphic arguments,
4797 : * but we do it anyway to be sure.
4798 : *
4799 : * Note: if any casts are needed, the args list is modified in-place;
4800 : * caller should have already copied the list structure.
4801 : */
4802 : static void
4803 11774 : recheck_cast_function_args(List *args, Oid result_type,
4804 : Oid *proargtypes, int pronargs,
4805 : HeapTuple func_tuple)
4806 : {
4807 11774 : Form_pg_proc funcform = (Form_pg_proc) GETSTRUCT(func_tuple);
4808 : int nargs;
4809 : Oid actual_arg_types[FUNC_MAX_ARGS];
4810 : Oid declared_arg_types[FUNC_MAX_ARGS];
4811 : Oid rettype;
4812 : ListCell *lc;
4813 :
4814 11774 : if (list_length(args) > FUNC_MAX_ARGS)
4815 0 : elog(ERROR, "too many function arguments");
4816 11774 : nargs = 0;
4817 57932 : foreach(lc, args)
4818 : {
4819 46158 : actual_arg_types[nargs++] = exprType((Node *) lfirst(lc));
4820 : }
4821 : Assert(nargs == pronargs);
4822 11774 : memcpy(declared_arg_types, proargtypes, pronargs * sizeof(Oid));
4823 11774 : rettype = enforce_generic_type_consistency(actual_arg_types,
4824 : declared_arg_types,
4825 : nargs,
4826 : funcform->prorettype,
4827 : false);
4828 : /* let's just check we got the same answer as the parser did ... */
4829 11774 : if (rettype != result_type)
4830 0 : elog(ERROR, "function's resolved result type changed during planning");
4831 :
4832 : /* perform any necessary typecasting of arguments */
4833 11774 : make_fn_arguments(NULL, args, actual_arg_types, declared_arg_types);
4834 11774 : }
4835 :
4836 : /*
4837 : * evaluate_function: try to pre-evaluate a function call
4838 : *
4839 : * We can do this if the function is strict and has any constant-null inputs
4840 : * (just return a null constant), or if the function is immutable and has all
4841 : * constant inputs (call it and return the result as a Const node). In
4842 : * estimation mode we are willing to pre-evaluate stable functions too.
4843 : *
4844 : * Returns a simplified expression if successful, or NULL if cannot
4845 : * simplify the function.
4846 : */
4847 : static Expr *
4848 700329 : evaluate_function(Oid funcid, Oid result_type, int32 result_typmod,
4849 : Oid result_collid, Oid input_collid, List *args,
4850 : bool funcvariadic,
4851 : HeapTuple func_tuple,
4852 : eval_const_expressions_context *context)
4853 : {
4854 700329 : Form_pg_proc funcform = (Form_pg_proc) GETSTRUCT(func_tuple);
4855 700329 : bool has_nonconst_input = false;
4856 700329 : bool has_null_input = false;
4857 : ListCell *arg;
4858 : FuncExpr *newexpr;
4859 :
4860 : /*
4861 : * Can't simplify if it returns a set.
4862 : */
4863 700329 : if (funcform->proretset)
4864 34741 : return NULL;
4865 :
4866 : /*
4867 : * Can't simplify if it returns RECORD. The immediate problem is that it
4868 : * will be needing an expected tupdesc which we can't supply here.
4869 : *
4870 : * In the case where it has OUT parameters, we could build an expected
4871 : * tupdesc from those, but there may be other gotchas lurking. In
4872 : * particular, if the function were to return NULL, we would produce a
4873 : * null constant with no remaining indication of which concrete record
4874 : * type it is. For now, seems best to leave the function call unreduced.
4875 : */
4876 665588 : if (funcform->prorettype == RECORDOID)
4877 2862 : return NULL;
4878 :
4879 : /*
4880 : * Check for constant inputs and especially constant-NULL inputs.
4881 : */
4882 1824459 : foreach(arg, args)
4883 : {
4884 1161733 : if (IsA(lfirst(arg), Const))
4885 525265 : has_null_input |= ((Const *) lfirst(arg))->constisnull;
4886 : else
4887 636468 : has_nonconst_input = true;
4888 : }
4889 :
4890 : /*
4891 : * If the function is strict and has a constant-NULL input, it will never
4892 : * be called at all, so we can replace the call by a NULL constant, even
4893 : * if there are other inputs that aren't constant, and even if the
4894 : * function is not otherwise immutable.
4895 : */
4896 662726 : if (funcform->proisstrict && has_null_input)
4897 2653 : return (Expr *) makeNullConst(result_type, result_typmod,
4898 : result_collid);
4899 :
4900 : /*
4901 : * Otherwise, can simplify only if all inputs are constants. (For a
4902 : * non-strict function, constant NULL inputs are treated the same as
4903 : * constant non-NULL inputs.)
4904 : */
4905 660073 : if (has_nonconst_input)
4906 486939 : return NULL;
4907 :
4908 : /*
4909 : * Ordinarily we are only allowed to simplify immutable functions. But for
4910 : * purposes of estimation, we consider it okay to simplify functions that
4911 : * are merely stable; the risk that the result might change from planning
4912 : * time to execution time is worth taking in preference to not being able
4913 : * to estimate the value at all.
4914 : */
4915 173134 : if (funcform->provolatile == PROVOLATILE_IMMUTABLE)
4916 : /* okay */ ;
4917 77480 : else if (context->estimate && funcform->provolatile == PROVOLATILE_STABLE)
4918 : /* okay */ ;
4919 : else
4920 75987 : return NULL;
4921 :
4922 : /*
4923 : * OK, looks like we can simplify this operator/function.
4924 : *
4925 : * Build a new FuncExpr node containing the already-simplified arguments.
4926 : */
4927 97147 : newexpr = makeNode(FuncExpr);
4928 97147 : newexpr->funcid = funcid;
4929 97147 : newexpr->funcresulttype = result_type;
4930 97147 : newexpr->funcretset = false;
4931 97147 : newexpr->funcvariadic = funcvariadic;
4932 97147 : newexpr->funcformat = COERCE_EXPLICIT_CALL; /* doesn't matter */
4933 97147 : newexpr->funccollid = result_collid; /* doesn't matter */
4934 97147 : newexpr->inputcollid = input_collid;
4935 97147 : newexpr->args = args;
4936 97147 : newexpr->location = -1;
4937 :
4938 97147 : return evaluate_expr((Expr *) newexpr, result_type, result_typmod,
4939 : result_collid);
4940 : }
4941 :
4942 : /*
4943 : * inline_function: try to expand a function call inline
4944 : *
4945 : * If the function is a sufficiently simple SQL-language function
4946 : * (just "SELECT expression"), then we can inline it and avoid the rather
4947 : * high per-call overhead of SQL functions. Furthermore, this can expose
4948 : * opportunities for constant-folding within the function expression.
4949 : *
4950 : * We have to beware of some special cases however. A directly or
4951 : * indirectly recursive function would cause us to recurse forever,
4952 : * so we keep track of which functions we are already expanding and
4953 : * do not re-expand them. Also, if a parameter is used more than once
4954 : * in the SQL-function body, we require it not to contain any volatile
4955 : * functions (volatiles might deliver inconsistent answers) nor to be
4956 : * unreasonably expensive to evaluate. The expensiveness check not only
4957 : * prevents us from doing multiple evaluations of an expensive parameter
4958 : * at runtime, but is a safety value to limit growth of an expression due
4959 : * to repeated inlining.
4960 : *
4961 : * We must also beware of changing the volatility or strictness status of
4962 : * functions by inlining them.
4963 : *
4964 : * Also, at the moment we can't inline functions returning RECORD. This
4965 : * doesn't work in the general case because it discards information such
4966 : * as OUT-parameter declarations.
4967 : *
4968 : * Also, context-dependent expression nodes in the argument list are trouble.
4969 : *
4970 : * Returns a simplified expression if successful, or NULL if cannot
4971 : * simplify the function.
4972 : */
4973 : static Expr *
4974 600466 : inline_function(Oid funcid, Oid result_type, Oid result_collid,
4975 : Oid input_collid, List *args,
4976 : bool funcvariadic,
4977 : HeapTuple func_tuple,
4978 : eval_const_expressions_context *context)
4979 : {
4980 600466 : Form_pg_proc funcform = (Form_pg_proc) GETSTRUCT(func_tuple);
4981 : char *src;
4982 : Datum tmp;
4983 : bool isNull;
4984 : MemoryContext oldcxt;
4985 : MemoryContext mycxt;
4986 : inline_error_callback_arg callback_arg;
4987 : ErrorContextCallback sqlerrcontext;
4988 : FuncExpr *fexpr;
4989 : SQLFunctionParseInfoPtr pinfo;
4990 : TupleDesc rettupdesc;
4991 : ParseState *pstate;
4992 : List *raw_parsetree_list;
4993 : List *querytree_list;
4994 : Query *querytree;
4995 : Node *newexpr;
4996 : int *usecounts;
4997 : ListCell *arg;
4998 : int i;
4999 :
5000 : /*
5001 : * Forget it if the function is not SQL-language or has other showstopper
5002 : * properties. (The prokind and nargs checks are just paranoia.)
5003 : */
5004 600466 : if (funcform->prolang != SQLlanguageId ||
5005 4517 : funcform->prokind != PROKIND_FUNCTION ||
5006 4517 : funcform->prosecdef ||
5007 4511 : funcform->proretset ||
5008 3798 : funcform->prorettype == RECORDOID ||
5009 7269 : !heap_attisnull(func_tuple, Anum_pg_proc_proconfig, NULL) ||
5010 3624 : funcform->pronargs != list_length(args))
5011 596842 : return NULL;
5012 :
5013 : /* Check for recursive function, and give up trying to expand if so */
5014 3624 : if (list_member_oid(context->active_fns, funcid))
5015 6 : return NULL;
5016 :
5017 : /* Check permission to call function (fail later, if not) */
5018 3618 : if (object_aclcheck(ProcedureRelationId, funcid, GetUserId(), ACL_EXECUTE) != ACLCHECK_OK)
5019 10 : return NULL;
5020 :
5021 : /* Check whether a plugin wants to hook function entry/exit */
5022 3608 : if (FmgrHookIsNeeded(funcid))
5023 0 : return NULL;
5024 :
5025 : /*
5026 : * Make a temporary memory context, so that we don't leak all the stuff
5027 : * that parsing might create.
5028 : */
5029 3608 : mycxt = AllocSetContextCreate(CurrentMemoryContext,
5030 : "inline_function",
5031 : ALLOCSET_DEFAULT_SIZES);
5032 3608 : oldcxt = MemoryContextSwitchTo(mycxt);
5033 :
5034 : /*
5035 : * We need a dummy FuncExpr node containing the already-simplified
5036 : * arguments. (In some cases we don't really need it, but building it is
5037 : * cheap enough that it's not worth contortions to avoid.)
5038 : */
5039 3608 : fexpr = makeNode(FuncExpr);
5040 3608 : fexpr->funcid = funcid;
5041 3608 : fexpr->funcresulttype = result_type;
5042 3608 : fexpr->funcretset = false;
5043 3608 : fexpr->funcvariadic = funcvariadic;
5044 3608 : fexpr->funcformat = COERCE_EXPLICIT_CALL; /* doesn't matter */
5045 3608 : fexpr->funccollid = result_collid; /* doesn't matter */
5046 3608 : fexpr->inputcollid = input_collid;
5047 3608 : fexpr->args = args;
5048 3608 : fexpr->location = -1;
5049 :
5050 : /* Fetch the function body */
5051 3608 : tmp = SysCacheGetAttrNotNull(PROCOID, func_tuple, Anum_pg_proc_prosrc);
5052 3608 : src = TextDatumGetCString(tmp);
5053 :
5054 : /*
5055 : * Setup error traceback support for ereport(). This is so that we can
5056 : * finger the function that bad information came from.
5057 : */
5058 3608 : callback_arg.proname = NameStr(funcform->proname);
5059 3608 : callback_arg.prosrc = src;
5060 :
5061 3608 : sqlerrcontext.callback = sql_inline_error_callback;
5062 3608 : sqlerrcontext.arg = &callback_arg;
5063 3608 : sqlerrcontext.previous = error_context_stack;
5064 3608 : error_context_stack = &sqlerrcontext;
5065 :
5066 : /* If we have prosqlbody, pay attention to that not prosrc */
5067 3608 : tmp = SysCacheGetAttr(PROCOID,
5068 : func_tuple,
5069 : Anum_pg_proc_prosqlbody,
5070 : &isNull);
5071 3608 : if (!isNull)
5072 : {
5073 : Node *n;
5074 : List *query_list;
5075 :
5076 2067 : n = stringToNode(TextDatumGetCString(tmp));
5077 2067 : if (IsA(n, List))
5078 1643 : query_list = linitial_node(List, castNode(List, n));
5079 : else
5080 424 : query_list = list_make1(n);
5081 2067 : if (list_length(query_list) != 1)
5082 3 : goto fail;
5083 2064 : querytree = linitial(query_list);
5084 :
5085 : /*
5086 : * Because we'll insist below that the querytree have an empty rtable
5087 : * and no sublinks, it cannot have any relation references that need
5088 : * to be locked or rewritten. So we can omit those steps.
5089 : */
5090 : }
5091 : else
5092 : {
5093 : /* Set up to handle parameters while parsing the function body. */
5094 1541 : pinfo = prepare_sql_fn_parse_info(func_tuple,
5095 : (Node *) fexpr,
5096 : input_collid);
5097 :
5098 : /*
5099 : * We just do parsing and parse analysis, not rewriting, because
5100 : * rewriting will not affect table-free-SELECT-only queries, which is
5101 : * all that we care about. Also, we can punt as soon as we detect
5102 : * more than one command in the function body.
5103 : */
5104 1541 : raw_parsetree_list = pg_parse_query(src);
5105 1541 : if (list_length(raw_parsetree_list) != 1)
5106 29 : goto fail;
5107 :
5108 1512 : pstate = make_parsestate(NULL);
5109 1512 : pstate->p_sourcetext = src;
5110 1512 : sql_fn_parser_setup(pstate, pinfo);
5111 :
5112 1512 : querytree = transformTopLevelStmt(pstate, linitial(raw_parsetree_list));
5113 :
5114 1509 : free_parsestate(pstate);
5115 : }
5116 :
5117 : /*
5118 : * The single command must be a simple "SELECT expression".
5119 : *
5120 : * Note: if you change the tests involved in this, see also plpgsql's
5121 : * exec_simple_check_plan(). That generally needs to have the same idea
5122 : * of what's a "simple expression", so that inlining a function that
5123 : * previously wasn't inlined won't change plpgsql's conclusion.
5124 : */
5125 3573 : if (!IsA(querytree, Query) ||
5126 3573 : querytree->commandType != CMD_SELECT ||
5127 3511 : querytree->hasAggs ||
5128 3436 : querytree->hasWindowFuncs ||
5129 3436 : querytree->hasTargetSRFs ||
5130 3436 : querytree->hasSubLinks ||
5131 2708 : querytree->cteList ||
5132 2708 : querytree->rtable ||
5133 1762 : querytree->jointree->fromlist ||
5134 1762 : querytree->jointree->quals ||
5135 1762 : querytree->groupClause ||
5136 1762 : querytree->groupingSets ||
5137 1762 : querytree->havingQual ||
5138 1762 : querytree->windowClause ||
5139 1762 : querytree->distinctClause ||
5140 1762 : querytree->sortClause ||
5141 1762 : querytree->limitOffset ||
5142 1762 : querytree->limitCount ||
5143 3450 : querytree->setOperations ||
5144 1725 : list_length(querytree->targetList) != 1)
5145 1878 : goto fail;
5146 :
5147 : /* If the function result is composite, resolve it */
5148 1695 : (void) get_expr_result_type((Node *) fexpr,
5149 : NULL,
5150 : &rettupdesc);
5151 :
5152 : /*
5153 : * Make sure the function (still) returns what it's declared to. This
5154 : * will raise an error if wrong, but that's okay since the function would
5155 : * fail at runtime anyway. Note that check_sql_fn_retval will also insert
5156 : * a coercion if needed to make the tlist expression match the declared
5157 : * type of the function.
5158 : *
5159 : * Note: we do not try this until we have verified that no rewriting was
5160 : * needed; that's probably not important, but let's be careful.
5161 : */
5162 1695 : querytree_list = list_make1(querytree);
5163 1695 : if (check_sql_fn_retval(list_make1(querytree_list),
5164 : result_type, rettupdesc,
5165 1695 : funcform->prokind,
5166 : false))
5167 6 : goto fail; /* reject whole-tuple-result cases */
5168 :
5169 : /*
5170 : * Given the tests above, check_sql_fn_retval shouldn't have decided to
5171 : * inject a projection step, but let's just make sure.
5172 : */
5173 1686 : if (querytree != linitial(querytree_list))
5174 0 : goto fail;
5175 :
5176 : /* Now we can grab the tlist expression */
5177 1686 : newexpr = (Node *) ((TargetEntry *) linitial(querytree->targetList))->expr;
5178 :
5179 : /*
5180 : * If the SQL function returns VOID, we can only inline it if it is a
5181 : * SELECT of an expression returning VOID (ie, it's just a redirection to
5182 : * another VOID-returning function). In all non-VOID-returning cases,
5183 : * check_sql_fn_retval should ensure that newexpr returns the function's
5184 : * declared result type, so this test shouldn't fail otherwise; but we may
5185 : * as well cope gracefully if it does.
5186 : */
5187 1686 : if (exprType(newexpr) != result_type)
5188 9 : goto fail;
5189 :
5190 : /*
5191 : * Additional validity checks on the expression. It mustn't be more
5192 : * volatile than the surrounding function (this is to avoid breaking hacks
5193 : * that involve pretending a function is immutable when it really ain't).
5194 : * If the surrounding function is declared strict, then the expression
5195 : * must contain only strict constructs and must use all of the function
5196 : * parameters (this is overkill, but an exact analysis is hard).
5197 : */
5198 2036 : if (funcform->provolatile == PROVOLATILE_IMMUTABLE &&
5199 359 : contain_mutable_functions(newexpr))
5200 6 : goto fail;
5201 2160 : else if (funcform->provolatile == PROVOLATILE_STABLE &&
5202 489 : contain_volatile_functions(newexpr))
5203 0 : goto fail;
5204 :
5205 2532 : if (funcform->proisstrict &&
5206 861 : contain_nonstrict_functions(newexpr))
5207 23 : goto fail;
5208 :
5209 : /*
5210 : * If any parameter expression contains a context-dependent node, we can't
5211 : * inline, for fear of putting such a node into the wrong context.
5212 : */
5213 1648 : if (contain_context_dependent_node((Node *) args))
5214 3 : goto fail;
5215 :
5216 : /*
5217 : * We may be able to do it; there are still checks on parameter usage to
5218 : * make, but those are most easily done in combination with the actual
5219 : * substitution of the inputs. So start building expression with inputs
5220 : * substituted.
5221 : */
5222 1645 : usecounts = (int *) palloc0(funcform->pronargs * sizeof(int));
5223 1645 : newexpr = substitute_actual_parameters(newexpr, funcform->pronargs,
5224 : args, usecounts);
5225 :
5226 : /* Now check for parameter usage */
5227 1645 : i = 0;
5228 4362 : foreach(arg, args)
5229 : {
5230 2717 : Node *param = lfirst(arg);
5231 :
5232 2717 : if (usecounts[i] == 0)
5233 : {
5234 : /* Param not used at all: uncool if func is strict */
5235 145 : if (funcform->proisstrict)
5236 0 : goto fail;
5237 : }
5238 2572 : else if (usecounts[i] != 1)
5239 : {
5240 : /* Param used multiple times: uncool if expensive or volatile */
5241 : QualCost eval_cost;
5242 :
5243 : /*
5244 : * We define "expensive" as "contains any subplan or more than 10
5245 : * operators". Note that the subplan search has to be done
5246 : * explicitly, since cost_qual_eval() will barf on unplanned
5247 : * subselects.
5248 : */
5249 231 : if (contain_subplans(param))
5250 0 : goto fail;
5251 231 : cost_qual_eval(&eval_cost, list_make1(param), NULL);
5252 231 : if (eval_cost.startup + eval_cost.per_tuple >
5253 231 : 10 * cpu_operator_cost)
5254 0 : goto fail;
5255 :
5256 : /*
5257 : * Check volatility last since this is more expensive than the
5258 : * above tests
5259 : */
5260 231 : if (contain_volatile_functions(param))
5261 0 : goto fail;
5262 : }
5263 2717 : i++;
5264 : }
5265 :
5266 : /*
5267 : * Whew --- we can make the substitution. Copy the modified expression
5268 : * out of the temporary memory context, and clean up.
5269 : */
5270 1645 : MemoryContextSwitchTo(oldcxt);
5271 :
5272 1645 : newexpr = copyObject(newexpr);
5273 :
5274 1645 : MemoryContextDelete(mycxt);
5275 :
5276 : /*
5277 : * If the result is of a collatable type, force the result to expose the
5278 : * correct collation. In most cases this does not matter, but it's
5279 : * possible that the function result is used directly as a sort key or in
5280 : * other places where we expect exprCollation() to tell the truth.
5281 : */
5282 1645 : if (OidIsValid(result_collid))
5283 : {
5284 745 : Oid exprcoll = exprCollation(newexpr);
5285 :
5286 745 : if (OidIsValid(exprcoll) && exprcoll != result_collid)
5287 : {
5288 18 : CollateExpr *newnode = makeNode(CollateExpr);
5289 :
5290 18 : newnode->arg = (Expr *) newexpr;
5291 18 : newnode->collOid = result_collid;
5292 18 : newnode->location = -1;
5293 :
5294 18 : newexpr = (Node *) newnode;
5295 : }
5296 : }
5297 :
5298 : /*
5299 : * Since there is now no trace of the function in the plan tree, we must
5300 : * explicitly record the plan's dependency on the function.
5301 : */
5302 1645 : if (context->root)
5303 1533 : record_plan_function_dependency(context->root, funcid);
5304 :
5305 : /*
5306 : * Recursively try to simplify the modified expression. Here we must add
5307 : * the current function to the context list of active functions.
5308 : */
5309 1645 : context->active_fns = lappend_oid(context->active_fns, funcid);
5310 1645 : newexpr = eval_const_expressions_mutator(newexpr, context);
5311 1644 : context->active_fns = list_delete_last(context->active_fns);
5312 :
5313 1644 : error_context_stack = sqlerrcontext.previous;
5314 :
5315 1644 : return (Expr *) newexpr;
5316 :
5317 : /* Here if func is not inlinable: release temp memory and return NULL */
5318 1957 : fail:
5319 1957 : MemoryContextSwitchTo(oldcxt);
5320 1957 : MemoryContextDelete(mycxt);
5321 1957 : error_context_stack = sqlerrcontext.previous;
5322 :
5323 1957 : return NULL;
5324 : }
5325 :
5326 : /*
5327 : * Replace Param nodes by appropriate actual parameters
5328 : */
5329 : static Node *
5330 1645 : substitute_actual_parameters(Node *expr, int nargs, List *args,
5331 : int *usecounts)
5332 : {
5333 : substitute_actual_parameters_context context;
5334 :
5335 1645 : context.nargs = nargs;
5336 1645 : context.args = args;
5337 1645 : context.usecounts = usecounts;
5338 :
5339 1645 : return substitute_actual_parameters_mutator(expr, &context);
5340 : }
5341 :
5342 : static Node *
5343 9587 : substitute_actual_parameters_mutator(Node *node,
5344 : substitute_actual_parameters_context *context)
5345 : {
5346 9587 : if (node == NULL)
5347 284 : return NULL;
5348 9303 : if (IsA(node, Param))
5349 : {
5350 2821 : Param *param = (Param *) node;
5351 :
5352 2821 : if (param->paramkind != PARAM_EXTERN)
5353 0 : elog(ERROR, "unexpected paramkind: %d", (int) param->paramkind);
5354 2821 : if (param->paramid <= 0 || param->paramid > context->nargs)
5355 0 : elog(ERROR, "invalid paramid: %d", param->paramid);
5356 :
5357 : /* Count usage of parameter */
5358 2821 : context->usecounts[param->paramid - 1]++;
5359 :
5360 : /* Select the appropriate actual arg and replace the Param with it */
5361 : /* We don't need to copy at this time (it'll get done later) */
5362 2821 : return list_nth(context->args, param->paramid - 1);
5363 : }
5364 6482 : return expression_tree_mutator(node, substitute_actual_parameters_mutator, context);
5365 : }
5366 :
5367 : /*
5368 : * error context callback to let us supply a call-stack traceback
5369 : */
5370 : static void
5371 10 : sql_inline_error_callback(void *arg)
5372 : {
5373 10 : inline_error_callback_arg *callback_arg = (inline_error_callback_arg *) arg;
5374 : int syntaxerrposition;
5375 :
5376 : /* If it's a syntax error, convert to internal syntax error report */
5377 10 : syntaxerrposition = geterrposition();
5378 10 : if (syntaxerrposition > 0)
5379 : {
5380 3 : errposition(0);
5381 3 : internalerrposition(syntaxerrposition);
5382 3 : internalerrquery(callback_arg->prosrc);
5383 : }
5384 :
5385 10 : errcontext("SQL function \"%s\" during inlining", callback_arg->proname);
5386 10 : }
5387 :
5388 : /*
5389 : * evaluate_expr: pre-evaluate a constant expression
5390 : *
5391 : * We use the executor's routine ExecEvalExpr() to avoid duplication of
5392 : * code and ensure we get the same result as the executor would get.
5393 : */
5394 : Expr *
5395 115109 : evaluate_expr(Expr *expr, Oid result_type, int32 result_typmod,
5396 : Oid result_collation)
5397 : {
5398 : EState *estate;
5399 : ExprState *exprstate;
5400 : MemoryContext oldcontext;
5401 : Datum const_val;
5402 : bool const_is_null;
5403 : int16 resultTypLen;
5404 : bool resultTypByVal;
5405 :
5406 : /*
5407 : * To use the executor, we need an EState.
5408 : */
5409 115109 : estate = CreateExecutorState();
5410 :
5411 : /* We can use the estate's working context to avoid memory leaks. */
5412 115109 : oldcontext = MemoryContextSwitchTo(estate->es_query_cxt);
5413 :
5414 : /* Make sure any opfuncids are filled in. */
5415 115109 : fix_opfuncids((Node *) expr);
5416 :
5417 : /*
5418 : * Prepare expr for execution. (Note: we can't use ExecPrepareExpr
5419 : * because it'd result in recursively invoking eval_const_expressions.)
5420 : */
5421 115109 : exprstate = ExecInitExpr(expr, NULL);
5422 :
5423 : /*
5424 : * And evaluate it.
5425 : *
5426 : * It is OK to use a default econtext because none of the ExecEvalExpr()
5427 : * code used in this situation will use econtext. That might seem
5428 : * fortuitous, but it's not so unreasonable --- a constant expression does
5429 : * not depend on context, by definition, n'est ce pas?
5430 : */
5431 115097 : const_val = ExecEvalExprSwitchContext(exprstate,
5432 115097 : GetPerTupleExprContext(estate),
5433 : &const_is_null);
5434 :
5435 : /* Get info needed about result datatype */
5436 113113 : get_typlenbyval(result_type, &resultTypLen, &resultTypByVal);
5437 :
5438 : /* Get back to outer memory context */
5439 113113 : MemoryContextSwitchTo(oldcontext);
5440 :
5441 : /*
5442 : * Must copy result out of sub-context used by expression eval.
5443 : *
5444 : * Also, if it's varlena, forcibly detoast it. This protects us against
5445 : * storing TOAST pointers into plans that might outlive the referenced
5446 : * data. (makeConst would handle detoasting anyway, but it's worth a few
5447 : * extra lines here so that we can do the copy and detoast in one step.)
5448 : */
5449 113113 : if (!const_is_null)
5450 : {
5451 110061 : if (resultTypLen == -1)
5452 44042 : const_val = PointerGetDatum(PG_DETOAST_DATUM_COPY(const_val));
5453 : else
5454 66019 : const_val = datumCopy(const_val, resultTypByVal, resultTypLen);
5455 : }
5456 :
5457 : /* Release all the junk we just created */
5458 113113 : FreeExecutorState(estate);
5459 :
5460 : /*
5461 : * Make the constant result node.
5462 : */
5463 113113 : return (Expr *) makeConst(result_type, result_typmod, result_collation,
5464 : resultTypLen,
5465 : const_val, const_is_null,
5466 : resultTypByVal);
5467 : }
5468 :
5469 :
5470 : /*
5471 : * inline_function_in_from
5472 : * Attempt to "inline" a function in the FROM clause.
5473 : *
5474 : * "rte" is an RTE_FUNCTION rangetable entry. If it represents a call of a
5475 : * function that can be inlined, expand the function and return the
5476 : * substitute Query structure. Otherwise, return NULL.
5477 : *
5478 : * We assume that the RTE's expression has already been put through
5479 : * eval_const_expressions(), which among other things will take care of
5480 : * default arguments and named-argument notation.
5481 : *
5482 : * This has a good deal of similarity to inline_function(), but that's
5483 : * for the general-expression case, and there are enough differences to
5484 : * justify separate functions.
5485 : */
5486 : Query *
5487 27651 : inline_function_in_from(PlannerInfo *root, RangeTblEntry *rte)
5488 : {
5489 : RangeTblFunction *rtfunc;
5490 : FuncExpr *fexpr;
5491 : Oid func_oid;
5492 : HeapTuple func_tuple;
5493 : Form_pg_proc funcform;
5494 : MemoryContext oldcxt;
5495 : MemoryContext mycxt;
5496 : Datum tmp;
5497 : char *src;
5498 : inline_error_callback_arg callback_arg;
5499 : ErrorContextCallback sqlerrcontext;
5500 27651 : Query *querytree = NULL;
5501 :
5502 : Assert(rte->rtekind == RTE_FUNCTION);
5503 :
5504 : /*
5505 : * Guard against infinite recursion during expansion by checking for stack
5506 : * overflow. (There's no need to do more.)
5507 : */
5508 27651 : check_stack_depth();
5509 :
5510 : /* Fail if the RTE has ORDINALITY - we don't implement that here. */
5511 27651 : if (rte->funcordinality)
5512 477 : return NULL;
5513 :
5514 : /* Fail if RTE isn't a single, simple FuncExpr */
5515 27174 : if (list_length(rte->functions) != 1)
5516 37 : return NULL;
5517 27137 : rtfunc = (RangeTblFunction *) linitial(rte->functions);
5518 :
5519 27137 : if (!IsA(rtfunc->funcexpr, FuncExpr))
5520 207 : return NULL;
5521 26930 : fexpr = (FuncExpr *) rtfunc->funcexpr;
5522 :
5523 26930 : func_oid = fexpr->funcid;
5524 :
5525 : /*
5526 : * Refuse to inline if the arguments contain any volatile functions or
5527 : * sub-selects. Volatile functions are rejected because inlining may
5528 : * result in the arguments being evaluated multiple times, risking a
5529 : * change in behavior. Sub-selects are rejected partly for implementation
5530 : * reasons (pushing them down another level might change their behavior)
5531 : * and partly because they're likely to be expensive and so multiple
5532 : * evaluation would be bad.
5533 : */
5534 53750 : if (contain_volatile_functions((Node *) fexpr->args) ||
5535 26820 : contain_subplans((Node *) fexpr->args))
5536 228 : return NULL;
5537 :
5538 : /* Check permission to call function (fail later, if not) */
5539 26702 : if (object_aclcheck(ProcedureRelationId, func_oid, GetUserId(), ACL_EXECUTE) != ACLCHECK_OK)
5540 6 : return NULL;
5541 :
5542 : /* Check whether a plugin wants to hook function entry/exit */
5543 26696 : if (FmgrHookIsNeeded(func_oid))
5544 0 : return NULL;
5545 :
5546 : /*
5547 : * OK, let's take a look at the function's pg_proc entry.
5548 : */
5549 26696 : func_tuple = SearchSysCache1(PROCOID, ObjectIdGetDatum(func_oid));
5550 26696 : if (!HeapTupleIsValid(func_tuple))
5551 0 : elog(ERROR, "cache lookup failed for function %u", func_oid);
5552 26696 : funcform = (Form_pg_proc) GETSTRUCT(func_tuple);
5553 :
5554 : /*
5555 : * If the function SETs any configuration parameters, inlining would cause
5556 : * us to miss making those changes.
5557 : */
5558 26696 : if (!heap_attisnull(func_tuple, Anum_pg_proc_proconfig, NULL))
5559 : {
5560 8 : ReleaseSysCache(func_tuple);
5561 8 : return NULL;
5562 : }
5563 :
5564 : /*
5565 : * Make a temporary memory context, so that we don't leak all the stuff
5566 : * that parsing and rewriting might create. If we succeed, we'll copy
5567 : * just the finished query tree back up to the caller's context.
5568 : */
5569 26688 : mycxt = AllocSetContextCreate(CurrentMemoryContext,
5570 : "inline_function_in_from",
5571 : ALLOCSET_DEFAULT_SIZES);
5572 26688 : oldcxt = MemoryContextSwitchTo(mycxt);
5573 :
5574 : /* Fetch the function body */
5575 26688 : tmp = SysCacheGetAttrNotNull(PROCOID, func_tuple, Anum_pg_proc_prosrc);
5576 26688 : src = TextDatumGetCString(tmp);
5577 :
5578 : /*
5579 : * If the function has an attached support function that can handle
5580 : * SupportRequestInlineInFrom, then attempt to inline with that.
5581 : */
5582 26688 : if (funcform->prosupport)
5583 : {
5584 : SupportRequestInlineInFrom req;
5585 :
5586 9239 : req.type = T_SupportRequestInlineInFrom;
5587 9239 : req.root = root;
5588 9239 : req.rtfunc = rtfunc;
5589 9239 : req.proc = func_tuple;
5590 :
5591 : querytree = (Query *)
5592 9239 : DatumGetPointer(OidFunctionCall1(funcform->prosupport,
5593 : PointerGetDatum(&req)));
5594 : }
5595 :
5596 : /*
5597 : * Setup error traceback support for ereport(). This is so that we can
5598 : * finger the function that bad information came from. We don't install
5599 : * this while running the support function, since it'd be likely to do the
5600 : * wrong thing: any parse errors reported during that are very likely not
5601 : * against the raw function source text.
5602 : */
5603 26688 : callback_arg.proname = NameStr(funcform->proname);
5604 26688 : callback_arg.prosrc = src;
5605 :
5606 26688 : sqlerrcontext.callback = sql_inline_error_callback;
5607 26688 : sqlerrcontext.arg = &callback_arg;
5608 26688 : sqlerrcontext.previous = error_context_stack;
5609 26688 : error_context_stack = &sqlerrcontext;
5610 :
5611 : /*
5612 : * If SupportRequestInlineInFrom didn't work, try our built-in inlining
5613 : * mechanism.
5614 : */
5615 26688 : if (!querytree)
5616 26676 : querytree = inline_sql_function_in_from(root, rtfunc, fexpr,
5617 : func_tuple, funcform, src);
5618 :
5619 26685 : if (!querytree)
5620 26562 : goto fail; /* no luck there either, fail */
5621 :
5622 : /*
5623 : * The result had better be a SELECT Query.
5624 : */
5625 : Assert(IsA(querytree, Query));
5626 : Assert(querytree->commandType == CMD_SELECT);
5627 :
5628 : /*
5629 : * Looks good --- substitute parameters into the query.
5630 : */
5631 123 : querytree = substitute_actual_parameters_in_from(querytree,
5632 123 : funcform->pronargs,
5633 : fexpr->args);
5634 :
5635 : /*
5636 : * Copy the modified query out of the temporary memory context, and clean
5637 : * up.
5638 : */
5639 123 : MemoryContextSwitchTo(oldcxt);
5640 :
5641 123 : querytree = copyObject(querytree);
5642 :
5643 123 : MemoryContextDelete(mycxt);
5644 123 : error_context_stack = sqlerrcontext.previous;
5645 123 : ReleaseSysCache(func_tuple);
5646 :
5647 : /*
5648 : * We don't have to fix collations here because the upper query is already
5649 : * parsed, ie, the collations in the RTE are what count.
5650 : */
5651 :
5652 : /*
5653 : * Since there is now no trace of the function in the plan tree, we must
5654 : * explicitly record the plan's dependency on the function.
5655 : */
5656 123 : record_plan_function_dependency(root, func_oid);
5657 :
5658 : /*
5659 : * We must also notice if the inserted query adds a dependency on the
5660 : * calling role due to RLS quals.
5661 : */
5662 123 : if (querytree->hasRowSecurity)
5663 36 : root->glob->dependsOnRole = true;
5664 :
5665 123 : return querytree;
5666 :
5667 : /* Here if func is not inlinable: release temp memory and return NULL */
5668 26562 : fail:
5669 26562 : MemoryContextSwitchTo(oldcxt);
5670 26562 : MemoryContextDelete(mycxt);
5671 26562 : error_context_stack = sqlerrcontext.previous;
5672 26562 : ReleaseSysCache(func_tuple);
5673 :
5674 26562 : return NULL;
5675 : }
5676 :
5677 : /*
5678 : * inline_sql_function_in_from
5679 : *
5680 : * This implements inline_function_in_from for SQL-language functions.
5681 : * Returns NULL if the function couldn't be inlined.
5682 : *
5683 : * The division of labor between here and inline_function_in_from is based
5684 : * on the rule that inline_function_in_from should make all checks that are
5685 : * certain to be required in both this case and the support-function case.
5686 : * Support functions might also want to make checks analogous to the ones
5687 : * made here, but then again they might not, or they might just assume that
5688 : * the function they are attached to can validly be inlined.
5689 : */
5690 : static Query *
5691 26676 : inline_sql_function_in_from(PlannerInfo *root,
5692 : RangeTblFunction *rtfunc,
5693 : FuncExpr *fexpr,
5694 : HeapTuple func_tuple,
5695 : Form_pg_proc funcform,
5696 : const char *src)
5697 : {
5698 : Datum sqlbody;
5699 : bool isNull;
5700 : List *querytree_list;
5701 : Query *querytree;
5702 : TypeFuncClass functypclass;
5703 : TupleDesc rettupdesc;
5704 :
5705 : /*
5706 : * The function must be declared to return a set, else inlining would
5707 : * change the results if the contained SELECT didn't return exactly one
5708 : * row.
5709 : */
5710 26676 : if (!fexpr->funcretset)
5711 4501 : return NULL;
5712 :
5713 : /*
5714 : * Forget it if the function is not SQL-language or has other showstopper
5715 : * properties. In particular it mustn't be declared STRICT, since we
5716 : * couldn't enforce that. It also mustn't be VOLATILE, because that is
5717 : * supposed to cause it to be executed with its own snapshot, rather than
5718 : * sharing the snapshot of the calling query. We also disallow returning
5719 : * SETOF VOID, because inlining would result in exposing the actual result
5720 : * of the function's last SELECT, which should not happen in that case.
5721 : * (Rechecking prokind, proretset, and pronargs is just paranoia.)
5722 : */
5723 22175 : if (funcform->prolang != SQLlanguageId ||
5724 324 : funcform->prokind != PROKIND_FUNCTION ||
5725 324 : funcform->proisstrict ||
5726 294 : funcform->provolatile == PROVOLATILE_VOLATILE ||
5727 117 : funcform->prorettype == VOIDOID ||
5728 114 : funcform->prosecdef ||
5729 114 : !funcform->proretset ||
5730 114 : list_length(fexpr->args) != funcform->pronargs)
5731 22061 : return NULL;
5732 :
5733 : /* If we have prosqlbody, pay attention to that not prosrc */
5734 114 : sqlbody = SysCacheGetAttr(PROCOID,
5735 : func_tuple,
5736 : Anum_pg_proc_prosqlbody,
5737 : &isNull);
5738 114 : if (!isNull)
5739 : {
5740 : Node *n;
5741 :
5742 6 : n = stringToNode(TextDatumGetCString(sqlbody));
5743 6 : if (IsA(n, List))
5744 6 : querytree_list = linitial_node(List, castNode(List, n));
5745 : else
5746 0 : querytree_list = list_make1(n);
5747 6 : if (list_length(querytree_list) != 1)
5748 0 : return NULL;
5749 6 : querytree = linitial(querytree_list);
5750 :
5751 : /* Acquire necessary locks, then apply rewriter. */
5752 6 : AcquireRewriteLocks(querytree, true, false);
5753 6 : querytree_list = pg_rewrite_query(querytree);
5754 6 : if (list_length(querytree_list) != 1)
5755 0 : return NULL;
5756 6 : querytree = linitial(querytree_list);
5757 : }
5758 : else
5759 : {
5760 : SQLFunctionParseInfoPtr pinfo;
5761 : List *raw_parsetree_list;
5762 :
5763 : /*
5764 : * Set up to handle parameters while parsing the function body. We
5765 : * can use the FuncExpr just created as the input for
5766 : * prepare_sql_fn_parse_info.
5767 : */
5768 108 : pinfo = prepare_sql_fn_parse_info(func_tuple,
5769 : (Node *) fexpr,
5770 : fexpr->inputcollid);
5771 :
5772 : /*
5773 : * Parse, analyze, and rewrite (unlike inline_function(), we can't
5774 : * skip rewriting here). We can fail as soon as we find more than one
5775 : * query, though.
5776 : */
5777 108 : raw_parsetree_list = pg_parse_query(src);
5778 108 : if (list_length(raw_parsetree_list) != 1)
5779 0 : return NULL;
5780 :
5781 108 : querytree_list = pg_analyze_and_rewrite_withcb(linitial(raw_parsetree_list),
5782 : src,
5783 : (ParserSetupHook) sql_fn_parser_setup,
5784 : pinfo, NULL);
5785 108 : if (list_length(querytree_list) != 1)
5786 0 : return NULL;
5787 108 : querytree = linitial(querytree_list);
5788 : }
5789 :
5790 : /*
5791 : * Also resolve the actual function result tupdesc, if composite. If we
5792 : * have a coldeflist, believe that; otherwise use get_expr_result_type.
5793 : * (This logic should match ExecInitFunctionScan.)
5794 : */
5795 114 : if (rtfunc->funccolnames != NIL)
5796 : {
5797 12 : functypclass = TYPEFUNC_RECORD;
5798 12 : rettupdesc = BuildDescFromLists(rtfunc->funccolnames,
5799 12 : rtfunc->funccoltypes,
5800 12 : rtfunc->funccoltypmods,
5801 12 : rtfunc->funccolcollations);
5802 : }
5803 : else
5804 102 : functypclass = get_expr_result_type((Node *) fexpr, NULL, &rettupdesc);
5805 :
5806 : /*
5807 : * The single command must be a plain SELECT.
5808 : */
5809 114 : if (!IsA(querytree, Query) ||
5810 114 : querytree->commandType != CMD_SELECT)
5811 0 : return NULL;
5812 :
5813 : /*
5814 : * Make sure the function (still) returns what it's declared to. This
5815 : * will raise an error if wrong, but that's okay since the function would
5816 : * fail at runtime anyway. Note that check_sql_fn_retval will also insert
5817 : * coercions if needed to make the tlist expression(s) match the declared
5818 : * type of the function. We also ask it to insert dummy NULL columns for
5819 : * any dropped columns in rettupdesc, so that the elements of the modified
5820 : * tlist match up to the attribute numbers.
5821 : *
5822 : * If the function returns a composite type, don't inline unless the check
5823 : * shows it's returning a whole tuple result; otherwise what it's
5824 : * returning is a single composite column which is not what we need.
5825 : */
5826 114 : if (!check_sql_fn_retval(list_make1(querytree_list),
5827 : fexpr->funcresulttype, rettupdesc,
5828 114 : funcform->prokind,
5829 45 : true) &&
5830 45 : (functypclass == TYPEFUNC_COMPOSITE ||
5831 45 : functypclass == TYPEFUNC_COMPOSITE_DOMAIN ||
5832 : functypclass == TYPEFUNC_RECORD))
5833 0 : return NULL; /* reject not-whole-tuple-result cases */
5834 :
5835 : /*
5836 : * check_sql_fn_retval might've inserted a projection step, but that's
5837 : * fine; just make sure we use the upper Query.
5838 : */
5839 111 : querytree = linitial_node(Query, querytree_list);
5840 :
5841 111 : return querytree;
5842 : }
5843 :
5844 : /*
5845 : * Replace Param nodes by appropriate actual parameters
5846 : *
5847 : * This is just enough different from substitute_actual_parameters()
5848 : * that it needs its own code.
5849 : */
5850 : static Query *
5851 123 : substitute_actual_parameters_in_from(Query *expr, int nargs, List *args)
5852 : {
5853 : substitute_actual_parameters_in_from_context context;
5854 :
5855 123 : context.nargs = nargs;
5856 123 : context.args = args;
5857 123 : context.sublevels_up = 1;
5858 :
5859 123 : return query_tree_mutator(expr,
5860 : substitute_actual_parameters_in_from_mutator,
5861 : &context,
5862 : 0);
5863 : }
5864 :
5865 : static Node *
5866 4419 : substitute_actual_parameters_in_from_mutator(Node *node,
5867 : substitute_actual_parameters_in_from_context *context)
5868 : {
5869 : Node *result;
5870 :
5871 4419 : if (node == NULL)
5872 2490 : return NULL;
5873 1929 : if (IsA(node, Query))
5874 : {
5875 75 : context->sublevels_up++;
5876 75 : result = (Node *) query_tree_mutator((Query *) node,
5877 : substitute_actual_parameters_in_from_mutator,
5878 : context,
5879 : 0);
5880 75 : context->sublevels_up--;
5881 75 : return result;
5882 : }
5883 1854 : if (IsA(node, Param))
5884 : {
5885 57 : Param *param = (Param *) node;
5886 :
5887 57 : if (param->paramkind == PARAM_EXTERN)
5888 : {
5889 57 : if (param->paramid <= 0 || param->paramid > context->nargs)
5890 0 : elog(ERROR, "invalid paramid: %d", param->paramid);
5891 :
5892 : /*
5893 : * Since the parameter is being inserted into a subquery, we must
5894 : * adjust levels.
5895 : */
5896 57 : result = copyObject(list_nth(context->args, param->paramid - 1));
5897 57 : IncrementVarSublevelsUp(result, context->sublevels_up, 0);
5898 57 : return result;
5899 : }
5900 : }
5901 1797 : return expression_tree_mutator(node,
5902 : substitute_actual_parameters_in_from_mutator,
5903 : context);
5904 : }
5905 :
5906 : /*
5907 : * pull_paramids
5908 : * Returns a Bitmapset containing the paramids of all Params in 'expr'.
5909 : */
5910 : Bitmapset *
5911 983 : pull_paramids(Expr *expr)
5912 : {
5913 983 : Bitmapset *result = NULL;
5914 :
5915 983 : (void) pull_paramids_walker((Node *) expr, &result);
5916 :
5917 983 : return result;
5918 : }
5919 :
5920 : static bool
5921 2180 : pull_paramids_walker(Node *node, Bitmapset **context)
5922 : {
5923 2180 : if (node == NULL)
5924 6 : return false;
5925 2174 : if (IsA(node, Param))
5926 : {
5927 1014 : Param *param = (Param *) node;
5928 :
5929 1014 : *context = bms_add_member(*context, param->paramid);
5930 1014 : return false;
5931 : }
5932 1160 : return expression_tree_walker(node, pull_paramids_walker, context);
5933 : }
5934 :
5935 : /*
5936 : * Build ScalarArrayOpExpr on top of 'exprs.' 'haveNonConst' indicates
5937 : * whether at least one of the expressions is not Const. When it's false,
5938 : * the array constant is built directly; otherwise, we have to build a child
5939 : * ArrayExpr. The 'exprs' list gets freed if not directly used in the output
5940 : * expression tree.
5941 : */
5942 : ScalarArrayOpExpr *
5943 1759 : make_SAOP_expr(Oid oper, Node *leftexpr, Oid coltype, Oid arraycollid,
5944 : Oid inputcollid, List *exprs, bool haveNonConst)
5945 : {
5946 1759 : Node *arrayNode = NULL;
5947 1759 : ScalarArrayOpExpr *saopexpr = NULL;
5948 1759 : Oid arraytype = get_array_type(coltype);
5949 :
5950 1759 : if (!OidIsValid(arraytype))
5951 0 : return NULL;
5952 :
5953 : /*
5954 : * Assemble an array from the list of constants. It seems more profitable
5955 : * to build a const array. But in the presence of other nodes, we don't
5956 : * have a specific value here and must employ an ArrayExpr instead.
5957 : */
5958 1759 : if (haveNonConst)
5959 : {
5960 48 : ArrayExpr *arrayExpr = makeNode(ArrayExpr);
5961 :
5962 : /* array_collid will be set by parse_collate.c */
5963 48 : arrayExpr->element_typeid = coltype;
5964 48 : arrayExpr->array_typeid = arraytype;
5965 48 : arrayExpr->multidims = false;
5966 48 : arrayExpr->elements = exprs;
5967 48 : arrayExpr->location = -1;
5968 :
5969 48 : arrayNode = (Node *) arrayExpr;
5970 : }
5971 : else
5972 : {
5973 : int16 typlen;
5974 : bool typbyval;
5975 : char typalign;
5976 : Datum *elems;
5977 : bool *nulls;
5978 1711 : int i = 0;
5979 : ArrayType *arrayConst;
5980 1711 : int dims[1] = {list_length(exprs)};
5981 1711 : int lbs[1] = {1};
5982 :
5983 1711 : get_typlenbyvalalign(coltype, &typlen, &typbyval, &typalign);
5984 :
5985 1711 : elems = palloc_array(Datum, list_length(exprs));
5986 1711 : nulls = palloc_array(bool, list_length(exprs));
5987 7087 : foreach_node(Const, value, exprs)
5988 : {
5989 3665 : elems[i] = value->constvalue;
5990 3665 : nulls[i++] = value->constisnull;
5991 : }
5992 :
5993 1711 : arrayConst = construct_md_array(elems, nulls, 1, dims, lbs,
5994 : coltype, typlen, typbyval, typalign);
5995 1711 : arrayNode = (Node *) makeConst(arraytype, -1, arraycollid,
5996 : -1, PointerGetDatum(arrayConst),
5997 : false, false);
5998 :
5999 1711 : pfree(elems);
6000 1711 : pfree(nulls);
6001 1711 : list_free(exprs);
6002 : }
6003 :
6004 : /* Build the SAOP expression node */
6005 1759 : saopexpr = makeNode(ScalarArrayOpExpr);
6006 1759 : saopexpr->opno = oper;
6007 1759 : saopexpr->opfuncid = get_opcode(oper);
6008 1759 : saopexpr->hashfuncid = InvalidOid;
6009 1759 : saopexpr->negfuncid = InvalidOid;
6010 1759 : saopexpr->useOr = true;
6011 1759 : saopexpr->inputcollid = inputcollid;
6012 1759 : saopexpr->args = list_make2(leftexpr, arrayNode);
6013 1759 : saopexpr->location = -1;
6014 :
6015 1759 : return saopexpr;
6016 : }
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