Обсуждение: calculated fields are not seen in the WHERE clause

Hello,

OK
select 1 as ccc where 1=1

ERROR
select 1 as ccc where ccc=1
PostgreSQL said: ERROR: Attribute 'ccc' not found

Is there any way to set conditions on calculated fields values?

Best regards,
Yar

Yaroslav Dmitriev kirjutas K, 30.10.2002 kell 13:48:
> Hello,
> 
> OK
> select 1 as ccc where 1=1
> 
> ERROR
> select 1 as ccc where ccc=1
> PostgreSQL said: ERROR: Attribute 'ccc' not found
> 
> Is there any way to set conditions on calculated fields values?

You could try using a subquery

select *from(select 1 as ccc) subwhere ccc=1

---------------
Hannu

AS strings are labels, not columns that can be referenced in a where
clause:
test=> select lanname as xx from pg_language where xx = 'yy';

Hannu is correct that making a FROM entry works.

---------------------------------------------------------------------------

Hannu Krosing wrote:
> Yaroslav Dmitriev kirjutas K, 30.10.2002 kell 13:48:
> > Hello,
> > 
> > OK
> > select 1 as ccc where 1=1
> > 
> > ERROR
> > select 1 as ccc where ccc=1
> > PostgreSQL said: ERROR: Attribute 'ccc' not found
> > 
> > Is there any way to set conditions on calculated fields values?
> 
> You could try using a subquery
> 
> select *
>  from
>  (select 1 as ccc) sub
>  where ccc=1
> 
> ---------------
> Hannu
> 
> 
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