diff options
| -rw-r--r-- | contrib/postgres_fdw/expected/postgres_fdw.out | 25 | ||||
| -rw-r--r-- | contrib/postgres_fdw/postgres_fdw.c | 55 | ||||
| -rw-r--r-- | contrib/postgres_fdw/sql/postgres_fdw.sql | 8 |
3 files changed, 86 insertions, 2 deletions
diff --git a/contrib/postgres_fdw/expected/postgres_fdw.out b/contrib/postgres_fdw/expected/postgres_fdw.out index f320a7578dd..0659656b6bb 100644 --- a/contrib/postgres_fdw/expected/postgres_fdw.out +++ b/contrib/postgres_fdw/expected/postgres_fdw.out @@ -5531,6 +5531,31 @@ UPDATE ft2 AS target SET (c2) = ( FROM ft2 AS src WHERE target.c1 = src.c1 ) WHERE c1 > 1100; +-- Test UPDATE involving a join that can be pushed down, +-- but a SET clause that can't be +EXPLAIN (VERBOSE, COSTS OFF) +UPDATE ft2 d SET c2 = CASE WHEN random() >= 0 THEN d.c2 ELSE 0 END + FROM ft2 AS t WHERE d.c1 = t.c1 AND d.c1 > 1100; + QUERY PLAN +----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- + Update on public.ft2 d + Remote SQL: UPDATE "S 1"."T 1" SET c2 = $2 WHERE ctid = $1 + -> Foreign Scan + Output: CASE WHEN (random() >= '0'::double precision) THEN d.c2 ELSE 0 END, d.ctid, d.*, t.* + Relations: (public.ft2 d) INNER JOIN (public.ft2 t) + Remote SQL: SELECT r1.c2, r1.ctid, CASE WHEN (r1.*)::text IS NOT NULL THEN ROW(r1."C 1", r1.c2, r1.c3, r1.c4, r1.c5, r1.c6, r1.c7, r1.c8) END, CASE WHEN (r2.*)::text IS NOT NULL THEN ROW(r2."C 1", r2.c2, r2.c3, r2.c4, r2.c5, r2.c6, r2.c7, r2.c8) END FROM ("S 1"."T 1" r1 INNER JOIN "S 1"."T 1" r2 ON (((r1."C 1" = r2."C 1")) AND ((r1."C 1" > 1100)))) FOR UPDATE OF r1 + -> Nested Loop + Output: d.c2, d.ctid, d.*, t.* + -> Foreign Scan on public.ft2 d + Output: d.c2, d.ctid, d.*, d.c1 + Remote SQL: SELECT "C 1", c2, c3, c4, c5, c6, c7, c8, ctid FROM "S 1"."T 1" WHERE (("C 1" > 1100)) ORDER BY "C 1" ASC NULLS LAST FOR UPDATE + -> Foreign Scan on public.ft2 t + Output: t.*, t.c1 + Remote SQL: SELECT "C 1", c2, c3, c4, c5, c6, c7, c8 FROM "S 1"."T 1" WHERE (($1::integer = "C 1")) +(14 rows) + +UPDATE ft2 d SET c2 = CASE WHEN random() >= 0 THEN d.c2 ELSE 0 END + FROM ft2 AS t WHERE d.c1 = t.c1 AND d.c1 > 1100; -- Test UPDATE/DELETE with WHERE or JOIN/ON conditions containing -- user-defined operators/functions ALTER SERVER loopback OPTIONS (DROP extensions); diff --git a/contrib/postgres_fdw/postgres_fdw.c b/contrib/postgres_fdw/postgres_fdw.c index c48a421e88b..0843ed9dba2 100644 --- a/contrib/postgres_fdw/postgres_fdw.c +++ b/contrib/postgres_fdw/postgres_fdw.c @@ -1440,6 +1440,57 @@ postgresGetForeignPlan(PlannerInfo *root, } /* + * Construct a tuple descriptor for the scan tuples handled by a foreign join. + */ +static TupleDesc +get_tupdesc_for_join_scan_tuples(ForeignScanState *node) +{ + ForeignScan *fsplan = (ForeignScan *) node->ss.ps.plan; + EState *estate = node->ss.ps.state; + TupleDesc tupdesc; + + /* + * The core code has already set up a scan tuple slot based on + * fsplan->fdw_scan_tlist, and this slot's tupdesc is mostly good enough, + * but there's one case where it isn't. If we have any whole-row row + * identifier Vars, they may have vartype RECORD, and we need to replace + * that with the associated table's actual composite type. This ensures + * that when we read those ROW() expression values from the remote server, + * we can convert them to a composite type the local server knows. + */ + tupdesc = CreateTupleDescCopy(node->ss.ss_ScanTupleSlot->tts_tupleDescriptor); + for (int i = 0; i < tupdesc->natts; i++) + { + Form_pg_attribute att = TupleDescAttr(tupdesc, i); + Var *var; + RangeTblEntry *rte; + Oid reltype; + + /* Nothing to do if it's not a generic RECORD attribute */ + if (att->atttypid != RECORDOID || att->atttypmod >= 0) + continue; + + /* + * If we can't identify the referenced table, do nothing. This'll + * likely lead to failure later, but perhaps we can muddle through. + */ + var = (Var *) list_nth_node(TargetEntry, fsplan->fdw_scan_tlist, + i)->expr; + if (!IsA(var, Var) || var->varattno != 0) + continue; + rte = list_nth(estate->es_range_table, var->varno - 1); + if (rte->rtekind != RTE_RELATION) + continue; + reltype = get_rel_type_id(rte->relid); + if (!OidIsValid(reltype)) + continue; + att->atttypid = reltype; + /* shouldn't need to change anything else */ + } + return tupdesc; +} + +/* * postgresBeginForeignScan * Initiate an executor scan of a foreign PostgreSQL table. */ @@ -1523,7 +1574,7 @@ postgresBeginForeignScan(ForeignScanState *node, int eflags) else { fsstate->rel = NULL; - fsstate->tupdesc = node->ss.ss_ScanTupleSlot->tts_tupleDescriptor; + fsstate->tupdesc = get_tupdesc_for_join_scan_tuples(node); } fsstate->attinmeta = TupleDescGetAttInMetadata(fsstate->tupdesc); @@ -2631,7 +2682,7 @@ postgresBeginDirectModify(ForeignScanState *node, int eflags) TupleDesc tupdesc; if (fsplan->scan.scanrelid == 0) - tupdesc = node->ss.ss_ScanTupleSlot->tts_tupleDescriptor; + tupdesc = get_tupdesc_for_join_scan_tuples(node); else tupdesc = RelationGetDescr(dmstate->rel); diff --git a/contrib/postgres_fdw/sql/postgres_fdw.sql b/contrib/postgres_fdw/sql/postgres_fdw.sql index 17dba77d7ec..79295e996dd 100644 --- a/contrib/postgres_fdw/sql/postgres_fdw.sql +++ b/contrib/postgres_fdw/sql/postgres_fdw.sql @@ -1255,6 +1255,14 @@ UPDATE ft2 AS target SET (c2) = ( WHERE target.c1 = src.c1 ) WHERE c1 > 1100; +-- Test UPDATE involving a join that can be pushed down, +-- but a SET clause that can't be +EXPLAIN (VERBOSE, COSTS OFF) +UPDATE ft2 d SET c2 = CASE WHEN random() >= 0 THEN d.c2 ELSE 0 END + FROM ft2 AS t WHERE d.c1 = t.c1 AND d.c1 > 1100; +UPDATE ft2 d SET c2 = CASE WHEN random() >= 0 THEN d.c2 ELSE 0 END + FROM ft2 AS t WHERE d.c1 = t.c1 AND d.c1 > 1100; + -- Test UPDATE/DELETE with WHERE or JOIN/ON conditions containing -- user-defined operators/functions ALTER SERVER loopback OPTIONS (DROP extensions); |