Remove incorrect Assert.

tglsfdc · tglsfdc · commit 77761ee5dddc · 2024-09-11T11:41:47.000-04:00
check_agglevels_and_constraints() asserted that if we find an aggregate function in an EXPR_KIND_FROM_SUBSELECT expression, the expression must be in a LATERAL subquery. Alexander Lakhin found a case where that's not so: because of the odd scoping rules for NEW/OLD within a rule, a reference to NEW/OLD could cause an aggregate to be considered top-level even though it's in an unmarked sub-select. The error message that would be thrown seems sufficiently on-point, so just remove the Assert. (Hence, this is not a bug for production builds.) This Assert was added by me in commit eaccfde (9.3 era). It looks like I put it in to cross-check that the new logic for detecting misplaced aggregates (using agglevelsup) caught the same cases that a previous check on p_lateral_active did. So there might have been some related misbehavior before eaccfde ... but that's very ancient history by now, so I didn't dig any deeper. Per bug #18608 from Alexander Lakhin. Back-patch to all supported branches. Discussion: https://postgr.es/m/18608-48de0717508ee429@postgresql.org
diff --git a/src/backend/parser/parse_agg.c b/src/backend/parser/parse_agg.c
@@ -381,8 +381,6 @@ check_agglevels_and_constraints(ParseState *pstate, Node *expr)
 
 			break;
 		case EXPR_KIND_FROM_SUBSELECT:
-			/* Should only be possible in a LATERAL subquery */
-			Assert(pstate->p_lateral_active);
 
 			/*
 			 * Aggregate/grouping scope rules make it worth being explicit
