| From: | Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> |
|---|---|
| To: | Tino Wildenhain <tino(at)wildenhain(dot)de> |
| Cc: | "Nigel J(dot) Andrews" <nandrews(at)investsystems(dot)co(dot)uk>, Pgsql-General <pgsql-general(at)postgresql(dot)org> |
| Subject: | Re: concenation of strings and null values |
| Date: | 2003-10-07 10:28:43 |
| Message-ID: | 23091.1065522523@sss.pgh.pa.us |
| Views: | Raw Message | Whole Thread | Download mbox | Resend email |
| Thread: | |
| Lists: | pgsql-general |
Tino Wildenhain <tino(at)wildenhain(dot)de> writes:
> Can someone enlighten me if this is
> in accordance to some not so transparent
> rules of SQL92 or '99 and if so, how
> to work around this?
It is per spec: in SQL92 6.13 <string value expression>:
2) If <concatenation> is specified, then let S1 and S2 be the re-
sult of the <character value expression> and <character factor>,
respectively.
Case:
a) If either S1 or S2 is the null value, then the result of the
<concatenation> is the null value.
regards, tom lane
| From | Date | Subject | |
|---|---|---|---|
| Next Message | Nagib Abi Fadel | 2003-10-07 10:38:32 | Problems defining a primary key !! |
| Previous Message | Peter Eisentraut | 2003-10-07 10:17:26 | Re: using copy to load odd characters |