From d2b89748e1b520c276875538149eb466e97c21b4 Mon Sep 17 00:00:00 2001 From: Pierre Date: Fri, 31 Jan 2020 23:58:35 +0100 Subject: [PATCH 1/2] Add support for IN clauses in dependencies check --- src/backend/statistics/dependencies.c | 34 +++++++++++++++++++++++++++ 1 file changed, 34 insertions(+) diff --git a/src/backend/statistics/dependencies.c b/src/backend/statistics/dependencies.c index e2f6c5bb97..d4844a9ec6 100644 --- a/src/backend/statistics/dependencies.c +++ b/src/backend/statistics/dependencies.c @@ -801,6 +801,40 @@ dependency_is_compatible_clause(Node *clause, Index relid, AttrNumber *attnum) /* OK to proceed with checking "var" */ } + else if (IsA(rinfo->clause, ScalarArrayOpExpr)) + { + /* If it's an opclause, check for Var IN Const. */ + ScalarArrayOpExpr *expr = (ScalarArrayOpExpr *) rinfo->clause; + + /* Only expressions with two arguments are candidates. */ + if (list_length(expr->args) != 2) + return false; + + /* Make sure non-selected argument is a pseudoconstant. */ + if (is_pseudo_constant_clause(lsecond(expr->args))) + var = linitial(expr->args); + else if (is_pseudo_constant_clause(linitial(expr->args))) + var = lsecond(expr->args); + else + return false; + + /* + * If it's not an "=" operator, just ignore the clause, as it's not + * compatible with functional dependencies. + * + * This uses the function for estimating selectivity, not the operator + * directly (a bit awkward, but well ...). + * + * XXX this is pretty dubious; probably it'd be better to check btree + * or hash opclass membership, so as not to be fooled by custom + * selectivity functions, and to be more consistent with decisions + * elsewhere in the planner. + */ + if (get_oprrest(expr->opno) != F_EQSEL) + return false; + + /* OK to proceed with checking "var" */ + } else if (is_notclause(rinfo->clause)) { /* -- 2.24.1