diff options
Diffstat (limited to 'src/backend/optimizer/util/relnode.c')
| -rw-r--r-- | src/backend/optimizer/util/relnode.c | 21 |
1 files changed, 21 insertions, 0 deletions
diff --git a/src/backend/optimizer/util/relnode.c b/src/backend/optimizer/util/relnode.c index 68a93a1a5bd..996b7fe5136 100644 --- a/src/backend/optimizer/util/relnode.c +++ b/src/backend/optimizer/util/relnode.c @@ -14,6 +14,7 @@ */ #include "postgres.h" +#include "optimizer/clauses.h" #include "optimizer/cost.h" #include "optimizer/pathnode.h" #include "optimizer/paths.h" @@ -102,6 +103,7 @@ build_simple_rel(PlannerInfo *root, int relid, RelOptKind reloptkind) /* cheap startup cost is interesting iff not all tuples to be retrieved */ rel->consider_startup = (root->tuple_fraction > 0); rel->consider_param_startup = false; /* might get changed later */ + rel->consider_parallel = false; /* might get changed later */ rel->reltargetlist = NIL; rel->pathlist = NIL; rel->ppilist = NIL; @@ -363,6 +365,7 @@ build_join_rel(PlannerInfo *root, /* cheap startup cost is interesting iff not all tuples to be retrieved */ joinrel->consider_startup = (root->tuple_fraction > 0); joinrel->consider_param_startup = false; + joinrel->consider_parallel = false; joinrel->reltargetlist = NIL; joinrel->pathlist = NIL; joinrel->ppilist = NIL; @@ -442,6 +445,24 @@ build_join_rel(PlannerInfo *root, sjinfo, restrictlist); /* + * Set the consider_parallel flag if this joinrel could potentially be + * scanned within a parallel worker. If this flag is false for either + * inner_rel or outer_rel, then it must be false for the joinrel also. + * Even if both are true, there might be parallel-restricted quals at + * our level. + * + * Note that if there are more than two rels in this relation, they + * could be divided between inner_rel and outer_rel in any arbitary + * way. We assume this doesn't matter, because we should hit all the + * same baserels and joinclauses while building up to this joinrel no + * matter which we take; therefore, we should make the same decision + * here however we get here. + */ + if (inner_rel->consider_parallel && outer_rel->consider_parallel && + !has_parallel_hazard((Node *) restrictlist, false)) + joinrel->consider_parallel = true; + + /* * Add the joinrel to the query's joinrel list, and store it into the * auxiliary hashtable if there is one. NB: GEQO requires us to append * the new joinrel to the end of the list! |