diff options
Diffstat (limited to 'contrib/postgres_fdw/postgres_fdw.c')
| -rw-r--r-- | contrib/postgres_fdw/postgres_fdw.c | 67 |
1 files changed, 58 insertions, 9 deletions
diff --git a/contrib/postgres_fdw/postgres_fdw.c b/contrib/postgres_fdw/postgres_fdw.c index 990313a5977..e8cb2d0b4da 100644 --- a/contrib/postgres_fdw/postgres_fdw.c +++ b/contrib/postgres_fdw/postgres_fdw.c @@ -669,6 +669,13 @@ postgresGetForeignRelSize(PlannerInfo *root, if (*refname && strcmp(refname, relname) != 0) appendStringInfo(fpinfo->relation_name, " %s", quote_identifier(rte->eref->aliasname)); + + /* No outer and inner relations. */ + fpinfo->make_outerrel_subquery = false; + fpinfo->make_innerrel_subquery = false; + fpinfo->lower_subquery_rels = NULL; + /* Set the relation index. */ + fpinfo->relation_index = baserel->relid; } /* @@ -1238,7 +1245,7 @@ postgresGetForeignPlan(PlannerInfo *root, initStringInfo(&sql); deparseSelectStmtForRel(&sql, root, foreignrel, fdw_scan_tlist, remote_conds, best_path->path.pathkeys, - &retrieved_attrs, ¶ms_list); + false, &retrieved_attrs, ¶ms_list); /* * Build the fdw_private list that will be available to the executor. @@ -2550,8 +2557,8 @@ estimate_path_cost_size(PlannerInfo *root, initStringInfo(&sql); appendStringInfoString(&sql, "EXPLAIN "); deparseSelectStmtForRel(&sql, root, foreignrel, fdw_scan_tlist, - remote_conds, pathkeys, &retrieved_attrs, - NULL); + remote_conds, pathkeys, false, + &retrieved_attrs, NULL); /* Get the remote estimate */ conn = GetConnection(fpinfo->user, false); @@ -4150,10 +4157,22 @@ foreign_join_ok(PlannerInfo *root, RelOptInfo *joinrel, JoinType jointype, fpinfo->jointype = jointype; /* + * By default, both the input relations are not required to be deparsed + * as subqueries, but there might be some relations covered by the input + * relations that are required to be deparsed as subqueries, so save the + * relids of those relations for later use by the deparser. + */ + fpinfo->make_outerrel_subquery = false; + fpinfo->make_innerrel_subquery = false; + Assert(bms_is_subset(fpinfo_o->lower_subquery_rels, outerrel->relids)); + Assert(bms_is_subset(fpinfo_i->lower_subquery_rels, innerrel->relids)); + fpinfo->lower_subquery_rels = bms_union(fpinfo_o->lower_subquery_rels, + fpinfo_i->lower_subquery_rels); + + /* * Pull the other remote conditions from the joining relations into join * clauses or other remote clauses (remote_conds) of this relation - * wherever possible. This avoids building subqueries at every join step, - * which is not currently supported by the deparser logic. + * wherever possible. This avoids building subqueries at every join step. * * For an inner join, clauses from both the relations are added to the * other remote clauses. For LEFT and RIGHT OUTER join, the clauses from @@ -4164,8 +4183,7 @@ foreign_join_ok(PlannerInfo *root, RelOptInfo *joinrel, JoinType jointype, * * For a FULL OUTER JOIN, the other clauses from either relation can not * be added to the joinclauses or remote_conds, since each relation acts - * as an outer relation for the other. Consider such full outer join as - * unshippable because of the reasons mentioned above in this comment. + * as an outer relation for the other. * * The joining sides can not have local conditions, thus no need to test * shippability of the clauses being pulled up. @@ -4194,8 +4212,29 @@ foreign_join_ok(PlannerInfo *root, RelOptInfo *joinrel, JoinType jointype, break; case JOIN_FULL: - if (fpinfo_i->remote_conds || fpinfo_o->remote_conds) - return false; + + /* + * In this case, if any of the input relations has conditions, + * we need to deparse that relation as a subquery so that the + * conditions can be evaluated before the join. Remember it in + * the fpinfo of this relation so that the deparser can take + * appropriate action. Also, save the relids of base relations + * covered by that relation for later use by the deparser. + */ + if (fpinfo_o->remote_conds) + { + fpinfo->make_outerrel_subquery = true; + fpinfo->lower_subquery_rels = + bms_add_members(fpinfo->lower_subquery_rels, + outerrel->relids); + } + if (fpinfo_i->remote_conds) + { + fpinfo->make_innerrel_subquery = true; + fpinfo->lower_subquery_rels = + bms_add_members(fpinfo->lower_subquery_rels, + innerrel->relids); + } break; default: @@ -4276,6 +4315,16 @@ foreign_join_ok(PlannerInfo *root, RelOptInfo *joinrel, JoinType jointype, get_jointype_name(fpinfo->jointype), fpinfo_i->relation_name->data); + /* + * Set the relation index. This is defined as the position of this + * joinrel in the join_rel_list list plus the length of the rtable list. + * Note that since this joinrel is at the end of the join_rel_list list + * when we are called, we can get the position by list_length. + */ + Assert(fpinfo->relation_index == 0); /* shouldn't be set yet */ + fpinfo->relation_index = + list_length(root->parse->rtable) + list_length(root->join_rel_list); + return true; } |