diff options
Diffstat (limited to 'src/backend/parser/parse_clause.c')
| -rw-r--r-- | src/backend/parser/parse_clause.c | 21 |
1 files changed, 10 insertions, 11 deletions
diff --git a/src/backend/parser/parse_clause.c b/src/backend/parser/parse_clause.c index fcee1379c0c..4931dcad3b6 100644 --- a/src/backend/parser/parse_clause.c +++ b/src/backend/parser/parse_clause.c @@ -332,7 +332,8 @@ transformJoinUsingClause(ParseState *pstate, RangeTblEntry *leftRTE, RangeTblEntry *rightRTE, List *leftVars, List *rightVars) { - Node *result = NULL; + Node *result; + List *andargs = NIL; ListCell *lvars, *rvars; @@ -358,18 +359,16 @@ transformJoinUsingClause(ParseState *pstate, copyObject(lvar), copyObject(rvar), -1); - /* And combine into an AND clause, if multiple join columns */ - if (result == NULL) - result = (Node *) e; - else - { - A_Expr *a; - - a = makeA_Expr(AEXPR_AND, NIL, result, (Node *) e, -1); - result = (Node *) a; - } + /* Prepare to combine into an AND clause, if multiple join columns */ + andargs = lappend(andargs, e); } + /* Only need an AND if there's more than one join column */ + if (list_length(andargs) == 1) + result = (Node *) linitial(andargs); + else + result = (Node *) makeBoolExpr(AND_EXPR, andargs, -1); + /* * Since the references are already Vars, and are certainly from the input * relations, we don't have to go through the same pushups that |