Обсуждение: cast bool/int

Hi,
I need a casting operator from boolean to integer,
tu put in ALTER TABLE statment after USING.

Any ideas? Thanks.

Zdravko

Στις Monday 23 March 2009 09:59:12 ο/η Zdravko Balorda έγραψε:
>
> Hi,
> I need a casting operator from boolean to integer,
> tu put in ALTER TABLE statment after USING.
>

How about
CASE WHEN 't' THEN 1 ELSE 0 END

> Any ideas? Thanks.
>
> Zdravko
>
>



--
Achilleas Mantzios

Στις Monday 23 March 2009 09:59:12 ο/η Zdravko Balorda έγραψε:
>
> Hi,
> I need a casting operator from boolean to integer,
> tu put in ALTER TABLE statment after USING.
>

Sorry in the above email i meant smth like
CASE WHEN column='t' THEN 1 ELSE 0 END

however
SELECT 't'::boolean::int;
int4
------   1
(1 row)

and
SELECT 'f'::boolean::int;int4
------   0
(1 row)

work in 8.3

> Any ideas? Thanks.
>
> Zdravko
>
>



--
Achilleas Mantzios

On Mon, Mar 23, 2009 at 10:18:31AM +0200, Achilleas Mantzios wrote:
> Στις Monday 23 March 2009 09:59:12 ο/η Zdravko Balorda έγραψε:
> >
> > Hi,
> > I need a casting operator from boolean to integer,
> > tu put in ALTER TABLE statment after USING.
> >
>
> Sorry in the above email i meant smth like
> CASE WHEN column='t' THEN 1 ELSE 0 END

Or just CASE WHEN column THEN 1 ELSE 0 END.

- Josh / eggyknap

>> CASE WHEN column='t' THEN 1 ELSE 0 END
> 
> Or just CASE WHEN column THEN 1 ELSE 0 END.

In the mean time I've got an elegant solution:

alter ... ... column TYPE smallint USING column::boolean::int::smallint;

It works, you wouldn't beleive it. ;)
Zdravko

On 2009-03-23, Zdravko Balorda <zdravko.balorda@siix.com> wrote:
>
> Hi,
> I need a casting operator from boolean to integer,
 you can use any expression....

> tu put in ALTER TABLE statment after USING.
>
> Any ideas? Thanks.
CASE WHEN columname THEN 1 WHEN NOT columname THEN 0 ELSE NULL END