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Thread: Referencing function value inside CASE..WHEN

Referencing function value inside CASE..WHEN

From
lover boi
Date:
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.

Re: Referencing function value inside CASE..WHEN

From
kleptog@svana.org
Date:
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Re: Referencing function value inside CASE..WHEN

From
"F. BROUARD / SQLpro"
Date:
Hi

Le 19/06/2011 04:27, lover boi a écrit :
> SELECT
>    MY_FUNCTION(...) AS my_function,
>    CASE WHEN my_function = '...' THEN '...' ELSE '...' END
> ...
> ...

WITH
T AS
(SELECT MY_FUNCTION(...) AS my_function, ...
)
SELECT CASE WHEN my_function = '...' THEN '...' ELSE '...' END
...
...

A +
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