| From: | David Johnston <polobo(at)yahoo(dot)com> |
|---|---|
| To: | lover boi <lover-boi(at)live(dot)co(dot)uk> |
| Cc: | "<pgsql-general(at)postgresql(dot)org>" <pgsql-general(at)postgresql(dot)org> |
| Subject: | Re: Referencing function value inside CASE..WHEN |
| Date: | 2011-06-19 04:03:53 |
| Message-ID: | AA299BBF-8E7E-443F-86C1-DABF23C5DDC9@yahoo.com |
| Views: | Raw Message | Whole Thread | Download mbox | Resend email |
| Thread: | |
| Lists: | pgsql-general |
You can try using a CTE/With clause. Failing that use a function with SELECT INTO...
On Jun 18, 2011, at 22:45, lover boi <lover-boi(at)live(dot)co(dot)uk> wrote:
> Hi,
>
> In the following statement, does the custom function get executed twice?
>
> SELECT
> MY_FUNCTION(...),
> CASE WHEN MY_FUNCTION(...) = '...' THEN '...' ELSE '...' END
> ...
> ...
>
>
> If so, is there a way I can make it execute once? I tried this but it gave me a "Column my_function does not exist" error.
>
> SELECT
>
> MY_FUNCTION(...) AS my_function,
>
> CASE WHEN my_function = '...' THEN '...' ELSE '...' END
>
> ...
>
> ...
>
>
> Thank you in advance.
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