[Mapserver-users] null values in postgis

[Kathi Koebke]

Hey Vladimir,

sorry that I'm  so late  with my answer, but here is my sql-statement. 
The result is an empty map in mapserver.
Maybe there' s something wrong in the sql-code or mapserver can't work 
with NULL values?  I don't know?

DATA "the_geom FROM xyz (SELECT ha_dk CASE WHEN ha_dk IS NULL THEN '' 
ELSE CAST(ha_dk AS VARCHAR) END AS ha_dk)"

EXPRESSION ([ha_dk] = '')

Tschüß Kathi
      
       

Vladimir Guzmán schrieb:

> I've had a simmilar problem, but with oracle, and what I did was a 
> casting, for example:
>
> data=the_geom FROM (SELECT CASE WHEN field IS NULL THEN ' ' ELSE 
> CAST(field AS VARCHAR) END AS field)
>
> And the expression would be:
> EXPRESSION ([field] = ' ')
>
> I don't know if there is a better way to do that, but it worked.
>
> Hope that helps,
>

-- 
Kathi Köbke
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