Line data Source code
1 : /*-------------------------------------------------------------------------
2 : *
3 : * rewriteGraphTable.c
4 : * Support for rewriting GRAPH_TABLE 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 : * IDENTIFICATION
10 : * src/backend/rewrite/rewriteGraphTable.c
11 : *
12 : *-------------------------------------------------------------------------
13 : */
14 : #include "postgres.h"
15 :
16 : #include "access/genam.h"
17 : #include "access/sysattr.h"
18 : #include "access/table.h"
19 : #include "access/htup_details.h"
20 : #include "catalog/pg_operator.h"
21 : #include "catalog/pg_propgraph_element.h"
22 : #include "catalog/pg_propgraph_element_label.h"
23 : #include "catalog/pg_propgraph_label.h"
24 : #include "catalog/pg_propgraph_label_property.h"
25 : #include "catalog/pg_propgraph_property.h"
26 : #include "miscadmin.h"
27 : #include "nodes/makefuncs.h"
28 : #include "nodes/nodeFuncs.h"
29 : #include "optimizer/optimizer.h"
30 : #include "parser/analyze.h"
31 : #include "parser/parse_collate.h"
32 : #include "parser/parse_func.h"
33 : #include "parser/parse_node.h"
34 : #include "parser/parse_oper.h"
35 : #include "parser/parse_relation.h"
36 : #include "parser/parsetree.h"
37 : #include "parser/parse_graphtable.h"
38 : #include "rewrite/rewriteGraphTable.h"
39 : #include "rewrite/rewriteHandler.h"
40 : #include "rewrite/rewriteManip.h"
41 : #include "utils/array.h"
42 : #include "utils/builtins.h"
43 : #include "utils/fmgroids.h"
44 : #include "utils/lsyscache.h"
45 : #include "utils/ruleutils.h"
46 : #include "utils/syscache.h"
47 :
48 :
49 : /*
50 : * Represents one path factor in a path.
51 : *
52 : * In a non-cyclic path, one path factor corresponds to one element pattern.
53 : *
54 : * In a cyclic path, one path factor corresponds to all the element patterns with
55 : * the same variable name.
56 : */
57 : struct path_factor
58 : {
59 : GraphElementPatternKind kind;
60 : const char *variable;
61 : Node *labelexpr;
62 : Node *whereClause;
63 : int factorpos; /* Position of this path factor in the list of
64 : * path factors representing a given path
65 : * pattern. */
66 : List *labeloids; /* OIDs of all the labels referenced in
67 : * labelexpr. */
68 : /* Links to adjacent vertex path factors if this is an edge path factor. */
69 : struct path_factor *src_pf;
70 : struct path_factor *dest_pf;
71 : };
72 :
73 : /*
74 : * Represents one property graph element (vertex or edge) in the path.
75 : *
76 : * Label expression in an element pattern resolves into a set of elements. We
77 : * create one path_element object for each of those elements.
78 : */
79 : struct path_element
80 : {
81 : /* Path factor from which this element is derived. */
82 : struct path_factor *path_factor;
83 : Oid elemoid;
84 : Oid reloid;
85 : /* Source and destination vertex elements for an edge element. */
86 : Oid srcvertexid;
87 : Oid destvertexid;
88 : /* Source and destination conditions for an edge element. */
89 : List *src_quals;
90 : List *dest_quals;
91 : };
92 :
93 : static Node *replace_property_refs(Oid propgraphid, Node *node, const List *mappings);
94 : static List *build_edge_vertex_link_quals(HeapTuple edgetup, int edgerti, int refrti, Oid refid, AttrNumber catalog_key_attnum, AttrNumber catalog_ref_attnum, AttrNumber catalog_eqop_attnum);
95 : static List *generate_queries_for_path_pattern(RangeTblEntry *rte, List *path_pattern);
96 : static Query *generate_query_for_graph_path(RangeTblEntry *rte, List *graph_path);
97 : static Node *generate_setop_from_pathqueries(List *pathqueries, List **rtable, List **targetlist);
98 : static List *generate_queries_for_path_pattern_recurse(RangeTblEntry *rte, List *pathqueries, List *cur_path, List *path_elem_lists, int elempos);
99 : static Query *generate_query_for_empty_path_pattern(RangeTblEntry *rte);
100 : static Query *generate_union_from_pathqueries(List **pathqueries);
101 : static List *get_path_elements_for_path_factor(Oid propgraphid, struct path_factor *pf);
102 : static bool is_property_associated_with_label(Oid labeloid, Oid propoid);
103 : static Node *get_element_property_expr(Oid elemoid, Oid propoid, int rtindex);
104 :
105 : /*
106 : * Convert GRAPH_TABLE clause into a subquery using relational
107 : * operators.
108 : */
109 : Query *
110 494 : rewriteGraphTable(Query *parsetree, int rt_index)
111 : {
112 : RangeTblEntry *rte;
113 : Query *graph_table_query;
114 : List *path_pattern;
115 494 : List *pathqueries = NIL;
116 :
117 494 : rte = rt_fetch(rt_index, parsetree->rtable);
118 :
119 : Assert(list_length(rte->graph_pattern->path_pattern_list) == 1);
120 :
121 494 : path_pattern = linitial(rte->graph_pattern->path_pattern_list);
122 494 : pathqueries = generate_queries_for_path_pattern(rte, path_pattern);
123 454 : graph_table_query = generate_union_from_pathqueries(&pathqueries);
124 :
125 454 : AcquireRewriteLocks(graph_table_query, true, false);
126 :
127 454 : rte->rtekind = RTE_SUBQUERY;
128 454 : rte->subquery = graph_table_query;
129 454 : rte->lateral = true;
130 :
131 : /*
132 : * Reset no longer applicable fields, to appease
133 : * WRITE_READ_PARSE_PLAN_TREES.
134 : */
135 454 : rte->graph_pattern = NULL;
136 454 : rte->graph_table_columns = NIL;
137 :
138 454 : return parsetree;
139 : }
140 :
141 : /*
142 : * Generate queries representing the given path pattern applied to the given
143 : * property graph.
144 : *
145 : * A path pattern consists of one or more element patterns. Each of the element
146 : * patterns may be satisfied by multiple elements. A path satisfying the given
147 : * path pattern consists of one element from each element pattern. There can be
148 : * as many paths as the number of combinations of the elements. A path pattern
149 : * in itself is a K-partite graph where K = number of element patterns in the
150 : * path pattern. The possible paths are computed by performing a DFS in this
151 : * graph. The DFS is implemented as recursion. Each of these paths is converted
152 : * into a query connecting all the elements in that path. Set of these queries is
153 : * returned.
154 : *
155 : * Between every two vertex elements in the path there is an edge element that
156 : * connects them. An edge connects two vertices identified by the source and
157 : * destination keys respectively. The connection between an edge and its
158 : * adjacent vertex is naturally computed as an equi-join between edge and vertex
159 : * table on their respective keys. Hence the query representing one path
160 : * consists of JOINs between edge and vertex tables.
161 : *
162 : * generate_queries_for_path_pattern() starts the recursion but actual work is
163 : * done by generate_queries_for_path_pattern_recurse().
164 : * generate_query_for_graph_path() constructs a query for a given path.
165 : *
166 : * A path pattern may end up producing no path if any of the element patterns
167 : * yields no elements or the edge patterns yield no edges connecting adjacent
168 : * vertex patterns. In such a case a dummy query which returns no result is
169 : * returned (generate_query_for_empty_path_pattern()).
170 : *
171 : * 'path_pattern' is given path pattern to be applied on the property graph in
172 : * the GRAPH_TABLE clause represented by given 'rte'.
173 : */
174 : static List *
175 494 : generate_queries_for_path_pattern(RangeTblEntry *rte, List *path_pattern)
176 : {
177 494 : List *pathqueries = NIL;
178 494 : List *path_elem_lists = NIL;
179 494 : int factorpos = 0;
180 494 : List *path_factors = NIL;
181 494 : struct path_factor *prev_pf = NULL;
182 :
183 : Assert(list_length(path_pattern) > 0);
184 :
185 : /*
186 : * Create a list of path factors representing the given path pattern
187 : * linking edge path factors to their adjacent vertex path factors.
188 : *
189 : * While doing that merge element patterns with the same variable name
190 : * into a single path_factor.
191 : */
192 2492 : foreach_node(GraphElementPattern, gep, path_pattern)
193 : {
194 1528 : struct path_factor *pf = NULL;
195 :
196 : /*
197 : * Unsupported conditions should have been caught by the parser
198 : * itself. We have corresponding Asserts here to document the
199 : * assumptions in this code.
200 : */
201 : Assert(gep->kind == VERTEX_PATTERN || IS_EDGE_PATTERN(gep->kind));
202 : Assert(!gep->quantifier);
203 :
204 4591 : foreach_ptr(struct path_factor, other, path_factors)
205 : {
206 1695 : if (gep->variable && other->variable &&
207 1109 : strcmp(gep->variable, other->variable) == 0)
208 : {
209 152 : if (other->kind != gep->kind)
210 4 : ereport(ERROR,
211 : (errcode(ERRCODE_WRONG_OBJECT_TYPE),
212 : errmsg("element patterns with same variable name \"%s\" but different element pattern types",
213 : gep->variable)));
214 :
215 : /*
216 : * If both the element patterns have label expressions, they
217 : * need to be conjuncted, which is not supported right now.
218 : *
219 : * However, an empty label expression means all labels.
220 : * Conjunction of any label expression with all labels is the
221 : * expression itself. Hence if only one of the two element
222 : * patterns has a label expression use that expression.
223 : */
224 148 : if (!other->labelexpr)
225 136 : other->labelexpr = gep->labelexpr;
226 12 : else if (gep->labelexpr && !equal(other->labelexpr, gep->labelexpr))
227 4 : ereport(ERROR,
228 : (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
229 : errmsg("element patterns with same variable name \"%s\" but different label expressions are not supported",
230 : gep->variable)));
231 :
232 : /*
233 : * If two element patterns have the same variable name, they
234 : * represent the same set of graph elements and hence are
235 : * constrained by conditions from both the element patterns.
236 : */
237 144 : if (!other->whereClause)
238 128 : other->whereClause = gep->whereClause;
239 16 : else if (gep->whereClause)
240 8 : other->whereClause = (Node *) makeBoolExpr(AND_EXPR,
241 8 : list_make2(other->whereClause, gep->whereClause),
242 : -1);
243 144 : pf = other;
244 144 : break;
245 : }
246 : }
247 :
248 1520 : if (!pf)
249 : {
250 1376 : pf = palloc0_object(struct path_factor);
251 1376 : pf->factorpos = factorpos++;
252 1376 : pf->kind = gep->kind;
253 1376 : pf->labelexpr = gep->labelexpr;
254 1376 : pf->variable = gep->variable;
255 1376 : pf->whereClause = gep->whereClause;
256 :
257 1376 : path_factors = lappend(path_factors, pf);
258 : }
259 :
260 : /*
261 : * Setup links to the previous path factor in the path.
262 : *
263 : * If the previous path factor represents an edge, this path factor
264 : * represents an adjacent vertex; the source vertex for an edge
265 : * pointing left or the destination vertex for an edge pointing right.
266 : * If this path factor represents an edge, the previous path factor
267 : * represents an adjacent vertex; source vertex for an edge pointing
268 : * right or the destination vertex for an edge pointing left.
269 : *
270 : * Edge pointing in any direction is treated similar to that pointing
271 : * in right direction here. When constructing a query in
272 : * generate_query_for_graph_path(), we will try links in both the
273 : * directions.
274 : *
275 : * If multiple edge patterns share the same variable name, they
276 : * constrain the adjacent vertex patterns since an edge can connect
277 : * only one pair of vertices. These adjacent vertex patterns need to
278 : * be merged even though they have different variables. Such element
279 : * patterns form a walk of graph where vertex and edges are repeated.
280 : * For example, in (a)-[b]->(c)<-[b]-(d), (a) and (d) represent the
281 : * same vertex element. This is slightly harder to implement and
282 : * probably less useful. Hence not supported for now.
283 : */
284 1520 : if (prev_pf)
285 : {
286 1026 : if (prev_pf->kind == EDGE_PATTERN_RIGHT || prev_pf->kind == EDGE_PATTERN_ANY)
287 : {
288 : Assert(!IS_EDGE_PATTERN(pf->kind));
289 501 : if (prev_pf->dest_pf && prev_pf->dest_pf != pf)
290 0 : ereport(ERROR,
291 : errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
292 : errmsg("an edge cannot connect more than two vertices even in a cyclic pattern"));
293 501 : prev_pf->dest_pf = pf;
294 : }
295 525 : else if (prev_pf->kind == EDGE_PATTERN_LEFT)
296 : {
297 : Assert(!IS_EDGE_PATTERN(pf->kind));
298 8 : if (prev_pf->src_pf && prev_pf->src_pf != pf)
299 0 : ereport(ERROR,
300 : errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
301 : errmsg("an edge cannot connect more than two vertices even in a cyclic pattern"));
302 8 : prev_pf->src_pf = pf;
303 : }
304 : else
305 : {
306 : Assert(prev_pf->kind == VERTEX_PATTERN);
307 : Assert(IS_EDGE_PATTERN(pf->kind));
308 : }
309 :
310 1026 : if (pf->kind == EDGE_PATTERN_RIGHT || pf->kind == EDGE_PATTERN_ANY)
311 : {
312 : Assert(!IS_EDGE_PATTERN(prev_pf->kind));
313 509 : if (pf->src_pf && pf->src_pf != prev_pf)
314 4 : ereport(ERROR,
315 : errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
316 : errmsg("an edge cannot connect more than two vertices even in a cyclic pattern"));
317 505 : pf->src_pf = prev_pf;
318 : }
319 517 : else if (pf->kind == EDGE_PATTERN_LEFT)
320 : {
321 : Assert(!IS_EDGE_PATTERN(prev_pf->kind));
322 8 : if (pf->dest_pf && pf->dest_pf != prev_pf)
323 0 : ereport(ERROR,
324 : errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
325 : errmsg("an edge cannot connect more than two vertices even in a cyclic pattern"));
326 8 : pf->dest_pf = prev_pf;
327 : }
328 : else
329 : {
330 : Assert(pf->kind == VERTEX_PATTERN);
331 : Assert(IS_EDGE_PATTERN(prev_pf->kind));
332 : }
333 : }
334 :
335 1516 : prev_pf = pf;
336 : }
337 :
338 : /*
339 : * Collect list of elements for each path factor. Do this after all the
340 : * edge links are setup correctly.
341 : */
342 2276 : foreach_ptr(struct path_factor, pf, path_factors)
343 1320 : path_elem_lists = lappend(path_elem_lists,
344 1328 : get_path_elements_for_path_factor(rte->relid, pf));
345 :
346 474 : pathqueries = generate_queries_for_path_pattern_recurse(rte, pathqueries,
347 : NIL, path_elem_lists, 0);
348 454 : if (!pathqueries)
349 4 : pathqueries = list_make1(generate_query_for_empty_path_pattern(rte));
350 :
351 454 : return pathqueries;
352 : }
353 :
354 : /*
355 : * Recursive workhorse function of generate_queries_for_path_pattern().
356 : *
357 : * `elempos` is the position of the next element being added in the path being
358 : * built.
359 : */
360 : static List *
361 10278 : generate_queries_for_path_pattern_recurse(RangeTblEntry *rte, List *pathqueries, List *cur_path, List *path_elem_lists, int elempos)
362 : {
363 10278 : List *path_elems = list_nth_node(List, path_elem_lists, elempos);
364 :
365 : /* Guard against stack overflow due to complex path patterns. */
366 10278 : check_stack_depth();
367 :
368 53533 : foreach_ptr(struct path_element, pe, path_elems)
369 : {
370 : /* Update current path being built with current element. */
371 33105 : cur_path = lappend(cur_path, pe);
372 :
373 : /*
374 : * If this is the last element in the path, generate query for the
375 : * completed path. Else recurse processing the next element.
376 : */
377 33105 : if (list_length(path_elem_lists) == list_length(cur_path))
378 : {
379 23301 : Query *pathquery = generate_query_for_graph_path(rte, cur_path);
380 :
381 : Assert(elempos == list_length(path_elem_lists) - 1);
382 23281 : if (pathquery)
383 837 : pathqueries = lappend(pathqueries, pathquery);
384 : }
385 : else
386 9804 : pathqueries = generate_queries_for_path_pattern_recurse(rte, pathqueries,
387 : cur_path,
388 : path_elem_lists,
389 : elempos + 1);
390 : /* Make way for the next element at the same position. */
391 33041 : cur_path = list_delete_last(cur_path);
392 : }
393 :
394 10214 : return pathqueries;
395 : }
396 :
397 : /*
398 : * Construct a query representing given graph path.
399 : *
400 : * The query contains:
401 : *
402 : * 1. targetlist corresponding to the COLUMNS clause of GRAPH_TABLE clause
403 : *
404 : * 2. quals corresponding to the WHERE clause of individual elements, WHERE
405 : * clause in GRAPH_TABLE clause and quals representing edge-vertex links.
406 : *
407 : * 3. fromlist containing all elements in the path
408 : *
409 : * The collations of property expressions are obtained from the catalog. The
410 : * collations of expressions in COLUMNS and WHERE clauses are assigned before
411 : * rewriting the graph table. The collations of the edge-vertex link quals are
412 : * assigned when crafting those quals. Thus everything in the query that requires
413 : * collation assignment has been taken care of already. No separate collation
414 : * assignment is required in this function.
415 : *
416 : * More details in the prologue of generate_queries_for_path_pattern().
417 : */
418 : static Query *
419 23301 : generate_query_for_graph_path(RangeTblEntry *rte, List *graph_path)
420 : {
421 23301 : Query *path_query = makeNode(Query);
422 23301 : List *fromlist = NIL;
423 23301 : List *qual_exprs = NIL;
424 : List *vars;
425 :
426 23301 : path_query->commandType = CMD_SELECT;
427 :
428 53537 : foreach_ptr(struct path_element, pe, graph_path)
429 : {
430 51823 : struct path_factor *pf = pe->path_factor;
431 : RangeTblRef *rtr;
432 : Relation rel;
433 : ParseNamespaceItem *pni;
434 :
435 : Assert(pf->kind == VERTEX_PATTERN || IS_EDGE_PATTERN(pf->kind));
436 :
437 : /* Add conditions representing edge connections. */
438 51823 : if (IS_EDGE_PATTERN(pf->kind))
439 : {
440 : struct path_element *src_pe;
441 : struct path_element *dest_pe;
442 25545 : Expr *edge_qual = NULL;
443 :
444 : Assert(pf->src_pf && pf->dest_pf);
445 25545 : src_pe = list_nth(graph_path, pf->src_pf->factorpos);
446 25545 : dest_pe = list_nth(graph_path, pf->dest_pf->factorpos);
447 :
448 : /* Make sure that the links of adjacent vertices are correct. */
449 : Assert(pf->src_pf == src_pe->path_factor &&
450 : pf->dest_pf == dest_pe->path_factor);
451 :
452 25545 : if (src_pe->elemoid == pe->srcvertexid &&
453 8817 : dest_pe->elemoid == pe->destvertexid)
454 3093 : edge_qual = makeBoolExpr(AND_EXPR,
455 3093 : list_concat(copyObject(pe->src_quals),
456 3093 : copyObject(pe->dest_quals)),
457 : -1);
458 :
459 : /*
460 : * An edge pattern in any direction matches edges in both
461 : * directions, try swapping source and destination. When the
462 : * source and destination is the same vertex table, quals
463 : * corresponding to either direction may get satisfied. Hence OR
464 : * the quals corresponding to both the directions.
465 : */
466 25545 : if (pf->kind == EDGE_PATTERN_ANY &&
467 224 : dest_pe->elemoid == pe->srcvertexid &&
468 80 : src_pe->elemoid == pe->destvertexid)
469 : {
470 24 : List *src_quals = copyObject(pe->dest_quals);
471 24 : List *dest_quals = copyObject(pe->src_quals);
472 : Expr *rev_edge_qual;
473 :
474 : /* Swap the source and destination varnos in the quals. */
475 24 : ChangeVarNodes((Node *) dest_quals, pe->path_factor->src_pf->factorpos + 1,
476 24 : pe->path_factor->dest_pf->factorpos + 1, 0);
477 24 : ChangeVarNodes((Node *) src_quals, pe->path_factor->dest_pf->factorpos + 1,
478 24 : pe->path_factor->src_pf->factorpos + 1, 0);
479 :
480 24 : rev_edge_qual = makeBoolExpr(AND_EXPR, list_concat(src_quals, dest_quals), -1);
481 24 : if (edge_qual)
482 16 : edge_qual = makeBoolExpr(OR_EXPR, list_make2(edge_qual, rev_edge_qual), -1);
483 : else
484 8 : edge_qual = rev_edge_qual;
485 : }
486 :
487 : /*
488 : * If the given edge element does not connect the adjacent vertex
489 : * elements in this path, the path is broken. Abandon this path as
490 : * it won't return any rows.
491 : */
492 25545 : if (edge_qual == NULL)
493 22444 : return NULL;
494 :
495 3101 : qual_exprs = lappend(qual_exprs, edge_qual);
496 : }
497 : else
498 : Assert(!pe->src_quals && !pe->dest_quals);
499 :
500 : /*
501 : * Create RangeTblEntry for this element table.
502 : *
503 : * SQL/PGQ standard (Ref. Section 11.19, Access rule 2 and General
504 : * rule 4) does not specify whose access privileges to use when
505 : * accessing the element tables: property graph owner's or current
506 : * user's. It is safer to use current user's privileges to avoid
507 : * unprivileged data access through a property graph. This is inline
508 : * with the views being security_invoker by default.
509 : */
510 29379 : rel = table_open(pe->reloid, AccessShareLock);
511 29379 : pni = addRangeTableEntryForRelation(make_parsestate(NULL), rel, AccessShareLock,
512 : NULL, true, false);
513 29379 : table_close(rel, NoLock);
514 29379 : path_query->rtable = lappend(path_query->rtable, pni->p_rte);
515 29379 : path_query->rteperminfos = lappend(path_query->rteperminfos, pni->p_perminfo);
516 29379 : pni->p_rte->perminfoindex = list_length(path_query->rteperminfos);
517 29379 : rtr = makeNode(RangeTblRef);
518 29379 : rtr->rtindex = list_length(path_query->rtable);
519 29379 : fromlist = lappend(fromlist, rtr);
520 :
521 : /*
522 : * Make sure that the assumption mentioned in create_pe_for_element()
523 : * holds true; that the elements' RangeTblEntrys are added in the
524 : * order in which their respective path factors appear in the list of
525 : * path factors representing the path pattern.
526 : */
527 : Assert(pf->factorpos + 1 == rtr->rtindex);
528 :
529 29379 : if (pf->whereClause)
530 : {
531 : Node *tr;
532 :
533 3744 : tr = replace_property_refs(rte->relid, pf->whereClause, list_make1(pe));
534 :
535 3744 : qual_exprs = lappend(qual_exprs, tr);
536 : }
537 : }
538 :
539 857 : if (rte->graph_pattern->whereClause)
540 : {
541 343 : Node *path_quals = replace_property_refs(rte->relid,
542 343 : (Node *) rte->graph_pattern->whereClause,
543 : graph_path);
544 :
545 343 : qual_exprs = lappend(qual_exprs, path_quals);
546 : }
547 :
548 1610 : path_query->jointree = makeFromExpr(fromlist,
549 753 : qual_exprs ? (Node *) makeBoolExpr(AND_EXPR, qual_exprs, -1) : NULL);
550 :
551 : /* Construct query targetlist from COLUMNS specification of GRAPH_TABLE. */
552 857 : path_query->targetList = castNode(List,
553 : replace_property_refs(rte->relid,
554 : (Node *) rte->graph_table_columns,
555 : graph_path));
556 :
557 : /*
558 : * Mark the columns being accessed in the path query as requiring SELECT
559 : * privilege. Any lateral columns should have been handled when the
560 : * corresponding ColumnRefs were transformed. Ignore those here.
561 : */
562 837 : vars = pull_vars_of_level((Node *) list_make2(qual_exprs, path_query->targetList), 0);
563 9849 : foreach_node(Var, var, vars)
564 : {
565 8175 : RTEPermissionInfo *perminfo = getRTEPermissionInfo(path_query->rteperminfos,
566 8175 : rt_fetch(var->varno, path_query->rtable));
567 :
568 : /* Must offset the attnum to fit in a bitmapset */
569 8175 : perminfo->selectedCols = bms_add_member(perminfo->selectedCols,
570 8175 : var->varattno - FirstLowInvalidHeapAttributeNumber);
571 : }
572 :
573 837 : return path_query;
574 : }
575 :
576 : /*
577 : * Construct a query which would not return any rows.
578 : *
579 : * More details in the prologue of generate_queries_for_path_pattern().
580 : */
581 : static Query *
582 4 : generate_query_for_empty_path_pattern(RangeTblEntry *rte)
583 : {
584 4 : Query *query = makeNode(Query);
585 :
586 4 : query->commandType = CMD_SELECT;
587 4 : query->rtable = NIL;
588 4 : query->rteperminfos = NIL;
589 4 : query->jointree = makeFromExpr(NIL, (Node *) makeBoolConst(false, false));
590 :
591 : /*
592 : * Even though no rows are returned, the result still projects the same
593 : * columns as projected by GRAPH_TABLE clause. Do this by constructing a
594 : * target list full of NULL values.
595 : */
596 16 : foreach_node(TargetEntry, te, rte->graph_table_columns)
597 : {
598 8 : Node *nte = (Node *) te->expr;
599 :
600 8 : te->expr = (Expr *) makeNullConst(exprType(nte), exprTypmod(nte), exprCollation(nte));
601 8 : query->targetList = lappend(query->targetList, te);
602 : }
603 :
604 4 : return query;
605 : }
606 :
607 : /*
608 : * Construct a query which is UNION of given path queries.
609 : *
610 : * The UNION query derives collations of its targetlist entries from the
611 : * corresponding targetlist entries of the path queries. The targetlists of path
612 : * queries being UNION'ed already have collations assigned. No separate
613 : * collation assignment required in this function.
614 : *
615 : * The function destroys given pathqueries list while constructing
616 : * SetOperationStmt recursively. Hence the function always returns with
617 : * `pathqueries` set to NIL.
618 : */
619 : static Query *
620 454 : generate_union_from_pathqueries(List **pathqueries)
621 : {
622 454 : List *rtable = NIL;
623 454 : Query *sampleQuery = linitial_node(Query, *pathqueries);
624 : SetOperationStmt *sostmt;
625 : Query *union_query;
626 : int resno;
627 : ListCell *lctl,
628 : *lct,
629 : *lcm,
630 : *lcc;
631 :
632 : Assert(list_length(*pathqueries) > 0);
633 :
634 : /* If there's only one pathquery, no need to construct a UNION query. */
635 454 : if (list_length(*pathqueries) == 1)
636 : {
637 323 : *pathqueries = NIL;
638 323 : return sampleQuery;
639 : }
640 :
641 131 : sostmt = castNode(SetOperationStmt,
642 : generate_setop_from_pathqueries(*pathqueries, &rtable, NULL));
643 :
644 : /* Encapsulate the set operation statement into a Query. */
645 131 : union_query = makeNode(Query);
646 131 : union_query->commandType = CMD_SELECT;
647 131 : union_query->rtable = rtable;
648 131 : union_query->setOperations = (Node *) sostmt;
649 131 : union_query->rteperminfos = NIL;
650 131 : union_query->jointree = makeFromExpr(NIL, NULL);
651 :
652 : /*
653 : * Generate dummy targetlist for outer query using column names from one
654 : * of the queries and common datatypes/collations of topmost set
655 : * operation. It shouldn't matter which query. Also it shouldn't matter
656 : * which RT index is used as varno in the target list entries, as long as
657 : * it corresponds to a real RT entry; else funny things may happen when
658 : * the tree is mashed by rule rewriting. So we use 1 since there's always
659 : * one RT entry at least.
660 : */
661 : Assert(rt_fetch(1, rtable));
662 131 : union_query->targetList = NULL;
663 131 : resno = 1;
664 480 : forfour(lct, sostmt->colTypes,
665 : lcm, sostmt->colTypmods,
666 : lcc, sostmt->colCollations,
667 : lctl, sampleQuery->targetList)
668 : {
669 349 : Oid colType = lfirst_oid(lct);
670 349 : int32 colTypmod = lfirst_int(lcm);
671 349 : Oid colCollation = lfirst_oid(lcc);
672 349 : TargetEntry *sample_tle = (TargetEntry *) lfirst(lctl);
673 : char *colName;
674 : TargetEntry *tle;
675 : Var *var;
676 :
677 : Assert(!sample_tle->resjunk);
678 349 : colName = pstrdup(sample_tle->resname);
679 349 : var = makeVar(1, sample_tle->resno, colType, colTypmod, colCollation, 0);
680 349 : var->location = exprLocation((Node *) sample_tle->expr);
681 349 : tle = makeTargetEntry((Expr *) var, (AttrNumber) resno++, colName, false);
682 349 : union_query->targetList = lappend(union_query->targetList, tle);
683 : }
684 :
685 131 : *pathqueries = NIL;
686 131 : return union_query;
687 : }
688 :
689 : /*
690 : * Construct a query which is UNION of all the given path queries.
691 : *
692 : * The function destroys given pathqueries list while constructing
693 : * SetOperationStmt recursively.
694 : */
695 : static Node *
696 649 : generate_setop_from_pathqueries(List *pathqueries, List **rtable, List **targetlist)
697 : {
698 : SetOperationStmt *sostmt;
699 : Query *lquery;
700 : Node *rarg;
701 649 : RangeTblRef *lrtr = makeNode(RangeTblRef);
702 : List *rtargetlist;
703 : ParseNamespaceItem *pni;
704 :
705 : /* Guard against stack overflow due to many path queries. */
706 649 : check_stack_depth();
707 :
708 : /* Recursion termination condition. */
709 649 : if (list_length(pathqueries) == 0)
710 : {
711 131 : *targetlist = NIL;
712 131 : return NULL;
713 : }
714 :
715 518 : lquery = linitial_node(Query, pathqueries);
716 :
717 : /*
718 : * Each path query will become a subquery of the UNION statement. So any
719 : * Vars that already refer outside the path query must be adjusted for
720 : * additional query level.
721 : */
722 518 : IncrementVarSublevelsUp((Node *) lquery, 1, 1);
723 :
724 518 : pni = addRangeTableEntryForSubquery(make_parsestate(NULL), lquery, NULL,
725 : false, false);
726 518 : *rtable = lappend(*rtable, pni->p_rte);
727 518 : lrtr->rtindex = list_length(*rtable);
728 518 : rarg = generate_setop_from_pathqueries(list_delete_first(pathqueries), rtable, &rtargetlist);
729 518 : if (rarg == NULL)
730 : {
731 : /*
732 : * No further path queries in the list. Convert the last query into a
733 : * RangeTblRef as expected by SetOperationStmt. Extract a list of the
734 : * non-junk TLEs for upper-level processing.
735 : */
736 131 : if (targetlist)
737 : {
738 131 : *targetlist = NIL;
739 611 : foreach_node(TargetEntry, tle, lquery->targetList)
740 : {
741 349 : if (!tle->resjunk)
742 349 : *targetlist = lappend(*targetlist, tle);
743 : }
744 : }
745 131 : return (Node *) lrtr;
746 : }
747 :
748 387 : sostmt = makeNode(SetOperationStmt);
749 387 : sostmt->op = SETOP_UNION;
750 387 : sostmt->all = true;
751 387 : sostmt->larg = (Node *) lrtr;
752 387 : sostmt->rarg = rarg;
753 387 : constructSetOpTargetlist(NULL, sostmt, lquery->targetList, rtargetlist, targetlist, "UNION", false);
754 :
755 387 : return (Node *) sostmt;
756 : }
757 :
758 : /*
759 : * Construct a path_element object for the graph element given by `elemoid`
760 : * satisfied by the path factor `pf`.
761 : *
762 : * If the type of graph element does not fit the element pattern kind, the
763 : * function returns NULL.
764 : */
765 : static struct path_element *
766 4617 : create_pe_for_element(struct path_factor *pf, Oid elemoid)
767 : {
768 4617 : HeapTuple eletup = SearchSysCache1(PROPGRAPHELOID, ObjectIdGetDatum(elemoid));
769 : Form_pg_propgraph_element pgeform;
770 : struct path_element *pe;
771 :
772 4617 : if (!eletup)
773 0 : elog(ERROR, "cache lookup failed for property graph element %u", elemoid);
774 4617 : pgeform = ((Form_pg_propgraph_element) GETSTRUCT(eletup));
775 :
776 4617 : if ((pgeform->pgekind == PGEKIND_VERTEX && pf->kind != VERTEX_PATTERN) ||
777 4001 : (pgeform->pgekind == PGEKIND_EDGE && !IS_EDGE_PATTERN(pf->kind)))
778 : {
779 1924 : ReleaseSysCache(eletup);
780 1924 : return NULL;
781 : }
782 :
783 2693 : pe = palloc0_object(struct path_element);
784 2693 : pe->path_factor = pf;
785 2693 : pe->elemoid = elemoid;
786 2693 : pe->reloid = pgeform->pgerelid;
787 :
788 : /*
789 : * When a path is converted into a query
790 : * (generate_query_for_graph_path()), a RangeTblEntry will be created for
791 : * every element in the path. Fixing rtindexes of RangeTblEntrys here
792 : * makes it possible to craft elements' qual expressions only once while
793 : * we have access to the catalog entry. Otherwise they need to be crafted
794 : * as many times as the number of paths a given element appears in,
795 : * fetching catalog entry again each time. Hence we simply assume
796 : * RangeTblEntrys will be created in the same order in which the
797 : * corresponding path factors appear in the list of path factors
798 : * representing a path pattern. That way their rtindexes will be same as
799 : * path_factor::factorpos + 1.
800 : */
801 2693 : if (IS_EDGE_PATTERN(pf->kind))
802 : {
803 1245 : pe->srcvertexid = pgeform->pgesrcvertexid;
804 1245 : pe->destvertexid = pgeform->pgedestvertexid;
805 : Assert(pf->src_pf && pf->dest_pf);
806 :
807 1245 : pe->src_quals = build_edge_vertex_link_quals(eletup, pf->factorpos + 1, pf->src_pf->factorpos + 1,
808 : pe->srcvertexid,
809 : Anum_pg_propgraph_element_pgesrckey,
810 : Anum_pg_propgraph_element_pgesrcref,
811 : Anum_pg_propgraph_element_pgesrceqop);
812 1245 : pe->dest_quals = build_edge_vertex_link_quals(eletup, pf->factorpos + 1, pf->dest_pf->factorpos + 1,
813 : pe->destvertexid,
814 : Anum_pg_propgraph_element_pgedestkey,
815 : Anum_pg_propgraph_element_pgedestref,
816 : Anum_pg_propgraph_element_pgedesteqop);
817 : }
818 :
819 2693 : ReleaseSysCache(eletup);
820 :
821 2693 : return pe;
822 : }
823 :
824 : /*
825 : * Returns the list of OIDs of graph labels which the given label expression
826 : * resolves to in the given property graph.
827 : */
828 : static List *
829 1328 : get_labels_for_expr(Oid propgraphid, Node *labelexpr)
830 : {
831 : List *label_oids;
832 :
833 1328 : if (!labelexpr)
834 : {
835 : Relation rel;
836 : SysScanDesc scan;
837 : ScanKeyData key[1];
838 : HeapTuple tup;
839 :
840 : /*
841 : * According to section 9.2 "Contextual inference of a set of labels"
842 : * subclause 2.a.ii of SQL/PGQ standard, element pattern which does
843 : * not have a label expression is considered to have label expression
844 : * equivalent to '%|!%' which is set of all labels.
845 : */
846 408 : label_oids = NIL;
847 408 : rel = table_open(PropgraphLabelRelationId, AccessShareLock);
848 408 : ScanKeyInit(&key[0],
849 : Anum_pg_propgraph_label_pglpgid,
850 : BTEqualStrategyNumber,
851 : F_OIDEQ, ObjectIdGetDatum(propgraphid));
852 408 : scan = systable_beginscan(rel, PropgraphLabelGraphNameIndexId,
853 : true, NULL, 1, key);
854 2728 : while (HeapTupleIsValid(tup = systable_getnext(scan)))
855 : {
856 2320 : Form_pg_propgraph_label label = (Form_pg_propgraph_label) GETSTRUCT(tup);
857 :
858 2320 : label_oids = lappend_oid(label_oids, label->oid);
859 : }
860 408 : systable_endscan(scan);
861 408 : table_close(rel, AccessShareLock);
862 : }
863 920 : else if (IsA(labelexpr, GraphLabelRef))
864 : {
865 874 : GraphLabelRef *glr = castNode(GraphLabelRef, labelexpr);
866 :
867 874 : label_oids = list_make1_oid(glr->labelid);
868 : }
869 46 : else if (IsA(labelexpr, BoolExpr))
870 : {
871 46 : BoolExpr *be = castNode(BoolExpr, labelexpr);
872 46 : List *label_exprs = be->args;
873 :
874 46 : label_oids = NIL;
875 188 : foreach_node(GraphLabelRef, glr, label_exprs)
876 96 : label_oids = lappend_oid(label_oids, glr->labelid);
877 : }
878 : else
879 : {
880 : /*
881 : * should not reach here since gram.y will not generate a label
882 : * expression with other node types.
883 : */
884 0 : elog(ERROR, "unsupported label expression node: %d", (int) nodeTag(labelexpr));
885 : }
886 :
887 1328 : return label_oids;
888 : }
889 :
890 : /*
891 : * Return a list of all the graph elements that satisfy the graph element pattern
892 : * represented by the given path_factor `pf`.
893 : *
894 : * First we find all the graph labels that satisfy the label expression in path
895 : * factor. Each label is associated with one or more graph elements. A union of
896 : * all such elements satisfies the element pattern. We create one path_element
897 : * object representing every element whose graph element kind qualifies the
898 : * element pattern kind. A list of all such path_element objects is returned.
899 : *
900 : * Note that we need to report an error for an explicitly specified label which
901 : * is not associated with any graph element of the required kind. So we have to
902 : * treat each label separately. Without that requirement we could have collected
903 : * all the unique elements first and then created path_element objects for them
904 : * to simplify the code.
905 : */
906 : static List *
907 1328 : get_path_elements_for_path_factor(Oid propgraphid, struct path_factor *pf)
908 : {
909 1328 : List *label_oids = get_labels_for_expr(propgraphid, pf->labelexpr);
910 1328 : List *elem_oids_seen = NIL;
911 1328 : List *pf_elem_oids = NIL;
912 1328 : List *path_elements = NIL;
913 1328 : List *unresolved_labels = NIL;
914 : Relation rel;
915 : SysScanDesc scan;
916 : ScanKeyData key[1];
917 : HeapTuple tup;
918 :
919 : /*
920 : * A property graph element can be either a vertex or an edge. Other types
921 : * of path factors like nested path pattern need to be handled separately
922 : * when supported.
923 : */
924 : Assert(pf->kind == VERTEX_PATTERN || IS_EDGE_PATTERN(pf->kind));
925 :
926 1328 : rel = table_open(PropgraphElementLabelRelationId, AccessShareLock);
927 5926 : foreach_oid(labeloid, label_oids)
928 : {
929 3286 : bool found = false;
930 :
931 3286 : ScanKeyInit(&key[0],
932 : Anum_pg_propgraph_element_label_pgellabelid,
933 : BTEqualStrategyNumber,
934 : F_OIDEQ, ObjectIdGetDatum(labeloid));
935 3286 : scan = systable_beginscan(rel, PropgraphElementLabelLabelIndexId, true,
936 : NULL, 1, key);
937 10981 : while (HeapTupleIsValid(tup = systable_getnext(scan)))
938 : {
939 7695 : Form_pg_propgraph_element_label label_elem = (Form_pg_propgraph_element_label) GETSTRUCT(tup);
940 7695 : Oid elem_oid = label_elem->pgelelid;
941 :
942 7695 : if (!list_member_oid(elem_oids_seen, elem_oid))
943 : {
944 : /*
945 : * Create path_element object if the new element qualifies the
946 : * element pattern kind.
947 : */
948 4617 : struct path_element *pe = create_pe_for_element(pf, elem_oid);
949 :
950 4617 : if (pe)
951 : {
952 2693 : path_elements = lappend(path_elements, pe);
953 :
954 : /* Remember qualified elements. */
955 2693 : pf_elem_oids = lappend_oid(pf_elem_oids, elem_oid);
956 2693 : found = true;
957 : }
958 :
959 : /*
960 : * Remember qualified and unqualified elements processed so
961 : * far to avoid processing already processed elements again.
962 : */
963 4617 : elem_oids_seen = lappend_oid(elem_oids_seen, label_elem->pgelelid);
964 : }
965 3078 : else if (list_member_oid(pf_elem_oids, elem_oid))
966 : {
967 : /*
968 : * The graph element is known to qualify the given element
969 : * pattern. Flag that the current label has at least one
970 : * qualified element associated with it.
971 : */
972 1582 : found = true;
973 : }
974 : }
975 :
976 3286 : if (!found)
977 : {
978 : /*
979 : * We did not find any qualified element associated with this
980 : * label. The label or its properties can not be associated with
981 : * the given element pattern. Throw an error if the label was
982 : * explicitly specified in the element pattern. Otherwise remember
983 : * it for later use.
984 : */
985 984 : if (!pf->labelexpr)
986 976 : unresolved_labels = lappend_oid(unresolved_labels, labeloid);
987 : else
988 8 : ereport(ERROR,
989 : (errcode(ERRCODE_UNDEFINED_OBJECT),
990 : errmsg("no property graph element of type \"%s\" has label \"%s\" associated with it in property graph \"%s\"",
991 : pf->kind == VERTEX_PATTERN ? "vertex" : "edge",
992 : get_propgraph_label_name(labeloid),
993 : get_rel_name(propgraphid))));
994 : }
995 :
996 3278 : systable_endscan(scan);
997 : }
998 1320 : table_close(rel, AccessShareLock);
999 :
1000 : /*
1001 : * Remove the labels which were not explicitly mentioned in the label
1002 : * expression but do not have any qualified elements associated with them.
1003 : * Properties associated with such labels may not be referenced. See
1004 : * replace_property_refs_mutator() for more details.
1005 : */
1006 1320 : pf->labeloids = list_difference_oid(label_oids, unresolved_labels);
1007 :
1008 1320 : return path_elements;
1009 : }
1010 :
1011 : /*
1012 : * Mutating property references into table variables
1013 : */
1014 :
1015 : struct replace_property_refs_context
1016 : {
1017 : Oid propgraphid;
1018 : const List *mappings;
1019 : };
1020 :
1021 : static Node *
1022 45384 : replace_property_refs_mutator(Node *node, struct replace_property_refs_context *context)
1023 : {
1024 45384 : if (node == NULL)
1025 0 : return NULL;
1026 45384 : if (IsA(node, Var))
1027 : {
1028 48 : Var *var = (Var *) node;
1029 48 : Var *newvar = copyObject(var);
1030 :
1031 : /*
1032 : * If it's already a Var, then it was a lateral reference. Since we
1033 : * are in a subquery after the rewrite, we have to increase the level
1034 : * by one.
1035 : */
1036 48 : newvar->varlevelsup++;
1037 :
1038 48 : return (Node *) newvar;
1039 : }
1040 45336 : else if (IsA(node, GraphPropertyRef))
1041 : {
1042 10951 : GraphPropertyRef *gpr = (GraphPropertyRef *) node;
1043 10951 : Node *n = NULL;
1044 10951 : struct path_element *found_mapping = NULL;
1045 10951 : struct path_factor *mapping_factor = NULL;
1046 10951 : List *unrelated_labels = NIL;
1047 :
1048 25193 : foreach_ptr(struct path_element, m, context->mappings)
1049 : {
1050 14242 : if (m->path_factor->variable && strcmp(gpr->elvarname, m->path_factor->variable) == 0)
1051 : {
1052 10951 : found_mapping = m;
1053 10951 : break;
1054 : }
1055 : }
1056 :
1057 : /*
1058 : * transformGraphTablePropertyRef() would not create a
1059 : * GraphPropertyRef for a variable which is not present in the graph
1060 : * path pattern.
1061 : */
1062 : Assert(found_mapping);
1063 :
1064 10951 : mapping_factor = found_mapping->path_factor;
1065 :
1066 : /*
1067 : * Find property definition for given element through any of the
1068 : * associated labels qualifying the given element pattern.
1069 : */
1070 59893 : foreach_oid(labeloid, mapping_factor->labeloids)
1071 : {
1072 37991 : Oid elem_labelid = GetSysCacheOid2(PROPGRAPHELEMENTLABELELEMENTLABEL,
1073 : Anum_pg_propgraph_element_label_oid,
1074 : ObjectIdGetDatum(found_mapping->elemoid),
1075 : ObjectIdGetDatum(labeloid));
1076 :
1077 37991 : if (OidIsValid(elem_labelid))
1078 : {
1079 23011 : HeapTuple tup = SearchSysCache2(PROPGRAPHLABELPROP, ObjectIdGetDatum(elem_labelid),
1080 : ObjectIdGetDatum(gpr->propid));
1081 :
1082 23011 : if (!tup)
1083 : {
1084 : /*
1085 : * The label is associated with the given element but it
1086 : * is not associated with the required property. Check
1087 : * next label.
1088 : */
1089 11720 : continue;
1090 : }
1091 :
1092 11291 : n = stringToNode(TextDatumGetCString(SysCacheGetAttrNotNull(PROPGRAPHLABELPROP,
1093 : tup, Anum_pg_propgraph_label_property_plpexpr)));
1094 11291 : ChangeVarNodes(n, 1, mapping_factor->factorpos + 1, 0);
1095 :
1096 11291 : ReleaseSysCache(tup);
1097 : }
1098 : else
1099 : {
1100 : /*
1101 : * Label is not associated with the element but it may be
1102 : * associated with the property through some other element.
1103 : * Save it for later use.
1104 : */
1105 14980 : unrelated_labels = lappend_oid(unrelated_labels, labeloid);
1106 : }
1107 : }
1108 :
1109 : /* See if we can resolve the property in some other way. */
1110 10951 : if (!n)
1111 : {
1112 72 : bool prop_associated = false;
1113 :
1114 168 : foreach_oid(loid, unrelated_labels)
1115 : {
1116 76 : if (is_property_associated_with_label(loid, gpr->propid))
1117 : {
1118 52 : prop_associated = true;
1119 52 : break;
1120 : }
1121 : }
1122 :
1123 72 : if (prop_associated)
1124 : {
1125 : /*
1126 : * The property is associated with at least one of the labels
1127 : * that satisfy given element pattern. If it's associated with
1128 : * the given element (through some other label), use
1129 : * corresponding value expression. Otherwise NULL. Ref.
1130 : * SQL/PGQ standard section 6.5 Property Reference, General
1131 : * Rule 2.b.
1132 : */
1133 52 : n = get_element_property_expr(found_mapping->elemoid, gpr->propid,
1134 52 : mapping_factor->factorpos + 1);
1135 :
1136 52 : if (!n)
1137 48 : n = (Node *) makeNullConst(gpr->typeId, gpr->typmod, gpr->collation);
1138 : }
1139 :
1140 : }
1141 :
1142 10951 : if (!n)
1143 20 : ereport(ERROR,
1144 : errcode(ERRCODE_UNDEFINED_OBJECT),
1145 : errmsg("property \"%s\" for element variable \"%s\" not found",
1146 : get_propgraph_property_name(gpr->propid), mapping_factor->variable));
1147 :
1148 10931 : return n;
1149 : }
1150 :
1151 34385 : return expression_tree_mutator(node, replace_property_refs_mutator, context);
1152 : }
1153 :
1154 : static Node *
1155 4944 : replace_property_refs(Oid propgraphid, Node *node, const List *mappings)
1156 : {
1157 : struct replace_property_refs_context context;
1158 :
1159 4944 : context.mappings = mappings;
1160 4944 : context.propgraphid = propgraphid;
1161 :
1162 4944 : return expression_tree_mutator(node, replace_property_refs_mutator, &context);
1163 : }
1164 :
1165 : /*
1166 : * Build join qualification expressions between edge and vertex tables.
1167 : */
1168 : static List *
1169 2490 : build_edge_vertex_link_quals(HeapTuple edgetup, int edgerti, int refrti, Oid refid, AttrNumber catalog_key_attnum, AttrNumber catalog_ref_attnum, AttrNumber catalog_eqop_attnum)
1170 : {
1171 2490 : List *quals = NIL;
1172 : Form_pg_propgraph_element pgeform;
1173 : Datum datum;
1174 : Datum *d1,
1175 : *d2,
1176 : *d3;
1177 : int n1,
1178 : n2,
1179 : n3;
1180 2490 : ParseState *pstate = make_parsestate(NULL);
1181 2490 : Oid refrelid = GetSysCacheOid1(PROPGRAPHELOID, Anum_pg_propgraph_element_pgerelid, ObjectIdGetDatum(refid));
1182 :
1183 2490 : pgeform = (Form_pg_propgraph_element) GETSTRUCT(edgetup);
1184 :
1185 2490 : datum = SysCacheGetAttrNotNull(PROPGRAPHELOID, edgetup, catalog_key_attnum);
1186 2490 : deconstruct_array_builtin(DatumGetArrayTypeP(datum), INT2OID, &d1, NULL, &n1);
1187 :
1188 2490 : datum = SysCacheGetAttrNotNull(PROPGRAPHELOID, edgetup, catalog_ref_attnum);
1189 2490 : deconstruct_array_builtin(DatumGetArrayTypeP(datum), INT2OID, &d2, NULL, &n2);
1190 :
1191 2490 : datum = SysCacheGetAttrNotNull(PROPGRAPHELOID, edgetup, catalog_eqop_attnum);
1192 2490 : deconstruct_array_builtin(DatumGetArrayTypeP(datum), OIDOID, &d3, NULL, &n3);
1193 :
1194 2490 : if (n1 != n2)
1195 0 : elog(ERROR, "array size key (%d) vs ref (%d) mismatch for element ID %u", catalog_key_attnum, catalog_ref_attnum, pgeform->oid);
1196 2490 : if (n1 != n3)
1197 0 : elog(ERROR, "array size key (%d) vs operator (%d) mismatch for element ID %u", catalog_key_attnum, catalog_eqop_attnum, pgeform->oid);
1198 :
1199 5644 : for (int i = 0; i < n1; i++)
1200 : {
1201 3154 : AttrNumber keyattn = DatumGetInt16(d1[i]);
1202 3154 : AttrNumber refattn = DatumGetInt16(d2[i]);
1203 3154 : Oid eqop = DatumGetObjectId(d3[i]);
1204 : Var *keyvar;
1205 : Var *refvar;
1206 : Oid atttypid;
1207 : int32 atttypmod;
1208 : Oid attcoll;
1209 : HeapTuple tup;
1210 : Form_pg_operator opform;
1211 : List *args;
1212 : Oid actual_arg_types[2];
1213 : Oid declared_arg_types[2];
1214 : OpExpr *linkqual;
1215 :
1216 3154 : get_atttypetypmodcoll(pgeform->pgerelid, keyattn, &atttypid, &atttypmod, &attcoll);
1217 3154 : keyvar = makeVar(edgerti, keyattn, atttypid, atttypmod, attcoll, 0);
1218 3154 : get_atttypetypmodcoll(refrelid, refattn, &atttypid, &atttypmod, &attcoll);
1219 3154 : refvar = makeVar(refrti, refattn, atttypid, atttypmod, attcoll, 0);
1220 :
1221 3154 : tup = SearchSysCache1(OPEROID, ObjectIdGetDatum(eqop));
1222 3154 : if (!HeapTupleIsValid(tup))
1223 0 : elog(ERROR, "cache lookup failed for operator %u", eqop);
1224 3154 : opform = (Form_pg_operator) GETSTRUCT(tup);
1225 : /* An equality operator is a binary operator returning boolean result. */
1226 : Assert(opform->oprkind == 'b'
1227 : && RegProcedureIsValid(opform->oprcode)
1228 : && opform->oprresult == BOOLOID
1229 : && !get_func_retset(opform->oprcode));
1230 :
1231 : /*
1232 : * Prepare operands and cast them to the types required by the
1233 : * equality operator. Similar to PK/FK quals, referenced vertex key is
1234 : * used as left operand and referencing edge key is used as right
1235 : * operand.
1236 : */
1237 3154 : args = list_make2(refvar, keyvar);
1238 3154 : actual_arg_types[0] = exprType((Node *) refvar);
1239 3154 : actual_arg_types[1] = exprType((Node *) keyvar);
1240 3154 : declared_arg_types[0] = opform->oprleft;
1241 3154 : declared_arg_types[1] = opform->oprright;
1242 3154 : make_fn_arguments(pstate, args, actual_arg_types, declared_arg_types);
1243 :
1244 3154 : linkqual = makeNode(OpExpr);
1245 3154 : linkqual->opno = opform->oid;
1246 3154 : linkqual->opfuncid = opform->oprcode;
1247 3154 : linkqual->opresulttype = opform->oprresult;
1248 3154 : linkqual->opretset = false;
1249 : /* opcollid and inputcollid will be set by parse_collate.c */
1250 3154 : linkqual->args = args;
1251 3154 : linkqual->location = -1;
1252 :
1253 3154 : ReleaseSysCache(tup);
1254 3154 : quals = lappend(quals, linkqual);
1255 : }
1256 :
1257 2490 : assign_expr_collations(pstate, (Node *) quals);
1258 :
1259 2490 : return quals;
1260 : }
1261 :
1262 : /*
1263 : * Check if the given property is associated with the given label.
1264 : *
1265 : * A label projects the same set of properties through every element it is
1266 : * associated with. Find any of the elements and return true if that element is
1267 : * associated with the given property. False otherwise.
1268 : */
1269 : static bool
1270 76 : is_property_associated_with_label(Oid labeloid, Oid propoid)
1271 : {
1272 : Relation rel;
1273 : SysScanDesc scan;
1274 : ScanKeyData key[1];
1275 : HeapTuple tup;
1276 76 : bool associated = false;
1277 :
1278 76 : rel = table_open(PropgraphElementLabelRelationId, RowShareLock);
1279 76 : ScanKeyInit(&key[0],
1280 : Anum_pg_propgraph_element_label_pgellabelid,
1281 : BTEqualStrategyNumber,
1282 : F_OIDEQ, ObjectIdGetDatum(labeloid));
1283 76 : scan = systable_beginscan(rel, PropgraphElementLabelLabelIndexId,
1284 : true, NULL, 1, key);
1285 :
1286 76 : if (HeapTupleIsValid(tup = systable_getnext(scan)))
1287 : {
1288 76 : Form_pg_propgraph_element_label ele_label = (Form_pg_propgraph_element_label) GETSTRUCT(tup);
1289 :
1290 76 : associated = SearchSysCacheExists2(PROPGRAPHLABELPROP,
1291 : ObjectIdGetDatum(ele_label->oid), ObjectIdGetDatum(propoid));
1292 : }
1293 76 : systable_endscan(scan);
1294 76 : table_close(rel, RowShareLock);
1295 :
1296 76 : return associated;
1297 : }
1298 :
1299 : /*
1300 : * If given element has the given property associated with it, through any of
1301 : * the associated labels, return value expression of the property. Otherwise
1302 : * NULL.
1303 : */
1304 : static Node *
1305 52 : get_element_property_expr(Oid elemoid, Oid propoid, int rtindex)
1306 : {
1307 : Relation rel;
1308 : SysScanDesc scan;
1309 : ScanKeyData key[1];
1310 : HeapTuple labeltup;
1311 52 : Node *n = NULL;
1312 :
1313 52 : rel = table_open(PropgraphElementLabelRelationId, RowShareLock);
1314 52 : ScanKeyInit(&key[0],
1315 : Anum_pg_propgraph_element_label_pgelelid,
1316 : BTEqualStrategyNumber,
1317 : F_OIDEQ, ObjectIdGetDatum(elemoid));
1318 52 : scan = systable_beginscan(rel, PropgraphElementLabelElementLabelIndexId,
1319 : true, NULL, 1, key);
1320 :
1321 148 : while (HeapTupleIsValid(labeltup = systable_getnext(scan)))
1322 : {
1323 100 : Form_pg_propgraph_element_label ele_label = (Form_pg_propgraph_element_label) GETSTRUCT(labeltup);
1324 :
1325 100 : HeapTuple proptup = SearchSysCache2(PROPGRAPHLABELPROP,
1326 : ObjectIdGetDatum(ele_label->oid), ObjectIdGetDatum(propoid));
1327 :
1328 100 : if (!proptup)
1329 96 : continue;
1330 4 : n = stringToNode(TextDatumGetCString(SysCacheGetAttrNotNull(PROPGRAPHLABELPROP,
1331 : proptup, Anum_pg_propgraph_label_property_plpexpr)));
1332 4 : ChangeVarNodes(n, 1, rtindex, 0);
1333 :
1334 4 : ReleaseSysCache(proptup);
1335 4 : break;
1336 : }
1337 52 : systable_endscan(scan);
1338 52 : table_close(rel, RowShareLock);
1339 :
1340 52 : return n;
1341 : }
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