diff --git a/src/backend/optimizer/util/var.c b/src/backend/optimizer/util/var.c index 19b2bba707..ad275cba3a 100644 --- a/src/backend/optimizer/util/var.c +++ b/src/backend/optimizer/util/var.c @@ -159,33 +159,28 @@ pull_varnos_walker(Node *node, pull_varnos_context *context) } if (IsA(node, PlaceHolderVar)) { - /* - * A PlaceHolderVar acts as a variable of its syntactic scope, or - * lower than that if it references only a subset of the rels in its - * syntactic scope. It might also contain lateral references, but we - * should ignore such references when computing the set of varnos in - * an expression tree. Also, if the PHV contains no variables within - * its syntactic scope, it will be forced to be evaluated exactly at - * the syntactic scope, so take that as the relid set. - */ PlaceHolderVar *phv = (PlaceHolderVar *) node; - pull_varnos_context subcontext; - subcontext.varnos = NULL; - subcontext.sublevels_up = context->sublevels_up; - (void) pull_varnos_walker((Node *) phv->phexpr, &subcontext); + /* + * If a PlaceHolderVar is not of the target query level, ignore it, + * instead recursing into its expression to see if it contains any + * vars that are of the target level. + */ if (phv->phlevelsup == context->sublevels_up) { - subcontext.varnos = bms_int_members(subcontext.varnos, - phv->phrels); - if (bms_is_empty(subcontext.varnos)) - context->varnos = bms_add_members(context->varnos, - phv->phrels); + /* + * Ideally, the PHV's contribution to context->varnos is its + * ph_eval_at set. However, this code can be invoked before + * that's been computed, and we lack easy access to it anyway. + * Instead make the conservative assumption that the PHV will be + * evaluated at its syntactic level (phv->phrels). + */ + context->varnos = bms_add_members(context->varnos, + phv->phrels); + return false; /* don't recurse into expression */ } - context->varnos = bms_join(context->varnos, subcontext.varnos); - return false; } - if (IsA(node, Query)) + else if (IsA(node, Query)) { /* Recurse into RTE subquery or not-yet-planned sublink subquery */ bool result; diff --git a/src/test/regress/expected/join.out b/src/test/regress/expected/join.out index 81b42c601b..43d684a11a 100644 --- a/src/test/regress/expected/join.out +++ b/src/test/regress/expected/join.out @@ -4726,18 +4726,22 @@ from left join uniquetbl u1 ON u1.f1 = t1.string4) ss on t0.f1 = ss.case1 where ss.stringu2 !~* ss.case1; - QUERY PLAN --------------------------------------------------------------------------------------------- + QUERY PLAN +---------------------------------------------------------------------------------------------- Nested Loop Join Filter: (CASE t1.ten WHEN 0 THEN 'doh!'::text ELSE NULL::text END = t0.f1) - -> Nested Loop - -> Seq Scan on int4_tbl i4 - -> Index Scan using tenk1_unique2 on tenk1 t1 - Index Cond: (unique2 = i4.f1) - Filter: (stringu2 !~* CASE ten WHEN 0 THEN 'doh!'::text ELSE NULL::text END) + -> Hash Right Join + Hash Cond: (u1.f1 = t1.string4) + Filter: (t1.stringu2 !~* (CASE t1.ten WHEN 0 THEN 'doh!'::text ELSE NULL::text END)) + -> Seq Scan on uniquetbl u1 + -> Hash + -> Nested Loop + -> Seq Scan on int4_tbl i4 + -> Index Scan using tenk1_unique2 on tenk1 t1 + Index Cond: (unique2 = i4.f1) -> Materialize -> Seq Scan on text_tbl t0 -(9 rows) +(13 rows) select t0.* from @@ -4756,6 +4760,42 @@ where ss.stringu2 !~* ss.case1; (1 row) rollback; +-- test case to expose miscomputation of required relid set for a PHV +explain (verbose, costs off) +select i8.*, ss.v, t.unique2 + from int8_tbl i8 + left join int4_tbl i4 on i4.f1 = 1 + left join lateral (select i4.f1 + 1 as v) as ss on true + left join tenk1 t on t.unique2 = ss.v +where q2 = 456; + QUERY PLAN +------------------------------------------------------------- + Nested Loop Left Join + Output: i8.q1, i8.q2, ((i4.f1 + 1)), t.unique2 + -> Nested Loop Left Join + Output: i8.q1, i8.q2, (i4.f1 + 1) + -> Seq Scan on public.int8_tbl i8 + Output: i8.q1, i8.q2 + Filter: (i8.q2 = 456) + -> Seq Scan on public.int4_tbl i4 + Output: i4.f1 + Filter: (i4.f1 = 1) + -> Index Only Scan using tenk1_unique2 on public.tenk1 t + Output: t.unique2 + Index Cond: (t.unique2 = ((i4.f1 + 1))) +(13 rows) + +select i8.*, ss.v, t.unique2 + from int8_tbl i8 + left join int4_tbl i4 on i4.f1 = 1 + left join lateral (select i4.f1 + 1 as v) as ss on true + left join tenk1 t on t.unique2 = ss.v +where q2 = 456; + q1 | q2 | v | unique2 +-----+-----+---+--------- + 123 | 456 | | +(1 row) + -- bug #8444: we've historically allowed duplicate aliases within aliased JOINs select * from int8_tbl x join (int4_tbl x cross join int4_tbl y) j on q1 = f1; -- error diff --git a/src/test/regress/sql/join.sql b/src/test/regress/sql/join.sql index 9887fe0c0b..6a209a27aa 100644 --- a/src/test/regress/sql/join.sql +++ b/src/test/regress/sql/join.sql @@ -1696,6 +1696,22 @@ where ss.stringu2 !~* ss.case1; rollback; +-- test case to expose miscomputation of required relid set for a PHV +explain (verbose, costs off) +select i8.*, ss.v, t.unique2 + from int8_tbl i8 + left join int4_tbl i4 on i4.f1 = 1 + left join lateral (select i4.f1 + 1 as v) as ss on true + left join tenk1 t on t.unique2 = ss.v +where q2 = 456; + +select i8.*, ss.v, t.unique2 + from int8_tbl i8 + left join int4_tbl i4 on i4.f1 = 1 + left join lateral (select i4.f1 + 1 as v) as ss on true + left join tenk1 t on t.unique2 = ss.v +where q2 = 456; + -- bug #8444: we've historically allowed duplicate aliases within aliased JOINs select * from