Fix to not allow null treatment to non window functions.

The null treatment clause (RESPECT NULLS/IGNORE NULLS) are only
allowed to window functions per spec. Previously the check was only
applied to aggregates in window clause. Other types of functions were
allowed to use the clause, which was plain wrong.

To fix this, ParseFuncOrColumn() now checks whether other than window
functions are used with the null treatment clause. If so, error out.

Also remove the unnecessary test for "aggregate functions do not
accept RESPECT/IGNORE NULLS" because it is now checked in the
early-stage new check. The window regression test expected file is
changed accordingly.

Reported-by: jian he <jian.universality@gmail.com>
Reviewed-by: jian he <jian.universality@gmail.com>
Author: Tatsuo Ishii <ishii@postgresql.org>
Discussion: https://postgr.es/m/CACJufxFnm%2BAj2Jyhyd58PtW8e1vTZDKimkZE%2BMashCPSDKw56Q%40mail.gmail.com
This commit is contained in:
Tatsuo Ishii 2026-06-17 10:12:07 +09:00
parent 9285737ac3
commit 4e5920e6de
2 changed files with 11 additions and 9 deletions

View file

@ -353,6 +353,15 @@ ParseFuncOrColumn(ParseState *pstate, List *funcname, List *fargs,
parser_errposition(pstate, location)));
}
/*
* NULL TREATEMENT is only allowed for window functions per spec.
*/
if (fdresult != FUNCDETAIL_WINDOWFUNC && ignore_nulls != NO_NULLTREATMENT)
ereport(ERROR,
errcode(ERRCODE_WRONG_OBJECT_TYPE),
errmsg("Only window functions accept RESPECT/IGNORE NULLS"),
parser_errposition(pstate, location));
/*
* So far so good, so do some fdresult-type-specific processing.
*/
@ -519,13 +528,6 @@ ParseFuncOrColumn(ParseState *pstate, List *funcname, List *fargs,
errmsg("%s is not an ordered-set aggregate, so it cannot have WITHIN GROUP",
NameListToString(funcname)),
parser_errposition(pstate, location)));
/* It also can't treat nulls as a window function */
if (ignore_nulls != NO_NULLTREATMENT)
ereport(ERROR,
(errcode(ERRCODE_WRONG_OBJECT_TYPE),
errmsg("aggregate functions do not accept RESPECT/IGNORE NULLS"),
parser_errposition(pstate, location)));
}
}
else if (fdresult == FUNCDETAIL_WINDOWFUNC)

View file

@ -5764,11 +5764,11 @@ SELECT sum(orbit) OVER () FROM planets; -- succeeds
(10 rows)
SELECT sum(orbit) RESPECT NULLS OVER () FROM planets; -- fails
ERROR: aggregate functions do not accept RESPECT/IGNORE NULLS
ERROR: Only window functions accept RESPECT/IGNORE NULLS
LINE 1: SELECT sum(orbit) RESPECT NULLS OVER () FROM planets;
^
SELECT sum(orbit) IGNORE NULLS OVER () FROM planets; -- fails
ERROR: aggregate functions do not accept RESPECT/IGNORE NULLS
ERROR: Only window functions accept RESPECT/IGNORE NULLS
LINE 1: SELECT sum(orbit) IGNORE NULLS OVER () FROM planets;
^
SELECT row_number() OVER () FROM planets; -- succeeds