From 7d2c7f08d9c5ad02101c0fb47cd8e859dd89083b Mon Sep 17 00:00:00 2001 From: David Rowley Date: Sun, 5 May 2024 12:54:46 +1200 Subject: Fix query pullup issue with WindowClause runCondition 94985c210 added code to detect when WindowFuncs were monotonic and allowed additional quals to be "pushed down" into the subquery to be used as WindowClause runConditions in order to short-circuit execution in nodeWindowAgg.c. The Node representation of runConditions wasn't well selected and because we do qual pushdown before planning the subquery, the planning of the subquery could perform subquery pull-up of nested subqueries. For WindowFuncs with args, the arguments could be changed after pushing the qual down to the subquery. This was made more difficult by the fact that the code duplicated the WindowFunc inside an OpExpr to include in the WindowClauses runCondition field. This could result in duplication of subqueries and a pull-up of such a subquery could result in another initplan parameter being issued for the 2nd version of the subplan. This could result in errors such as: ERROR: WindowFunc not found in subplan target lists To fix this, we change the node representation of these run conditions and instead of storing an OpExpr containing the WindowFunc in a list inside WindowClause, we now store a new node type named WindowFuncRunCondition within a new field in the WindowFunc. These get transformed into OpExprs later in planning once subquery pull-up has been performed. This problem did exist in v15 and v16, but that was fixed by 9d36b883b and e5d20bbd. Cat version bump due to new node type and modifying WindowFunc struct. Bug: #18305 Reported-by: Zuming Jiang Discussion: https://postgr.es/m/18305-33c49b4c830b37b3%40postgresql.org --- src/backend/parser/parse_expr.c | 1 + 1 file changed, 1 insertion(+) (limited to 'src/backend/parser/parse_expr.c') diff --git a/src/backend/parser/parse_expr.c b/src/backend/parser/parse_expr.c index 1c1c86aa3e9..aba3546ed1a 100644 --- a/src/backend/parser/parse_expr.c +++ b/src/backend/parser/parse_expr.c @@ -3826,6 +3826,7 @@ transformJsonAggConstructor(ParseState *pstate, JsonAggConstructor *agg_ctor, /* wincollid and inputcollid will be set by parse_collate.c */ wfunc->args = args; wfunc->aggfilter = aggfilter; + wfunc->runCondition = NIL; /* winref will be set by transformWindowFuncCall */ wfunc->winstar = false; wfunc->winagg = true; -- cgit v1.2.3