| From: | Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> |
|---|---|
| To: | ivningman(at)gmail(dot)com |
| Cc: | pgsql-bugs(at)lists(dot)postgresql(dot)org |
| Subject: | Re: BUG #18542: Order by expression, that contains column from projection isn't working |
| Date: | 2024-07-16 12:45:15 |
| Message-ID: | 3319082.1721133915@sss.pgh.pa.us |
| Views: | Raw Message | Whole Thread | Download mbox | Resend email |
| Thread: | |
| Lists: | pgsql-bugs |
PG Bug reporting form <noreply(at)postgresql(dot)org> writes:
> select z as y from
> (select 1 as z) x
> order by y + 1
> That query finishes with error:
> ERROR: column "y" does not exist
> Position: 48
> But wrapping it with select works fine:
> select * from (select z as y from
> (select 1 as z) x) c
> order by y + 1
This is not a bug. See
https://www.postgresql.org/docs/current/queries-order.html
particularly "Note that an output column name has to stand alone, that
is, it cannot be used in an expression". The fact that we allow this
at all is a hangover from SQL92; per SQL99 and later, variables in
ORDER BY should refer to input columns (that is, outputs of the FROM
clause).
regards, tom lane
| From | Date | Subject | |
|---|---|---|---|
| Next Message | PG Bug reporting form | 2024-07-17 12:53:39 | BUG #18543: Mistake in docs example |
| Previous Message | Etsuro Fujita | 2024-07-16 10:29:16 | Re: BUG #17889: Invalid cursor direction for a foreign scan that reached the fetch_size (MOVE BACKWARD ALL IN cX) |