diff --git a/src/backend/parser/analyze.c b/src/backend/parser/analyze.c
index 28fed9d87f6..209edf85e94 100644
--- a/src/backend/parser/analyze.c
+++ b/src/backend/parser/analyze.c
@@ -2790,6 +2790,7 @@ transformPLAssignStmt(ParseState *pstate, PLAssignStmt *stmt)
 											qry->sortClause,
 											EXPR_KIND_GROUP_BY,
 											false /* allow SQL92 rules */ );
+	qry->groupDistinct = sstmt->groupDistinct;
 
 	if (sstmt->distinctClause == NIL)
 	{