Re: calculated fields are not seen in the WHERE clause - Mailing list pgsql-hackers

From Bruce Momjian
Subject Re: calculated fields are not seen in the WHERE clause
Date
Msg-id 200211020039.gA20d7b19756@candle.pha.pa.us
Whole thread Raw
In response to Re: calculated fields are not seen in the WHERE clause  (Hannu Krosing <hannu@tm.ee>)
List pgsql-hackers
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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