Обсуждение: [7.3.x] function does not exist ... ?

'k, this doesn't look right, but it could be that I'm overlooking
something ...

The function I created:

CREATE FUNCTION month_trunc (timestamp without time zone) RETURNS timestamp without time zone   AS 'SELECT
date_trunc(''month'',$1 )'   LANGUAGE sql IMMUTABLE;
 


The query that fails:

ams=# select * from traffic_logs where month_trunc(runtime) = month_trunc(now());
ERROR:  Function month_trunc(timestamp with time zone) does not exist       Unable to identify a function that
satisfiesthe given argument types       You may need to add explicit typecasts
 

The query that succeeds:

ams=# explain select * from traffic_logs where month_trunc(runtime) = '2003-10-01';
 QUERY PLAN
 
-------------------------------------------------------------------------------------------Index Scan using tl_month on
traffic_logs (cost=0.00..30751.90 rows=8211 width=36)  Index Cond: (month_trunc(runtime) = '2003-10-01
00:00:00'::timestampwithout time zone)
 
(2 rows)

I haven't mis-spelt anything that I can see ... is this something that is
known not to be doable?

Marc G. Fournier wrote:

> 'k, this doesn't look right, but it could be that I'm overlooking
> something ...
> 
> The function I created:
> 
> CREATE FUNCTION month_trunc (timestamp without time zone) RETURNS timestamp without time zone
>     AS 'SELECT date_trunc(''month'', $1 )'
>     LANGUAGE sql IMMUTABLE;
> 
> 
> The query that fails:
> 
> ams=# select * from traffic_logs where month_trunc(runtime) = month_trunc(now());
> ERROR:  Function month_trunc(timestamp with time zone) does not exist
>         Unable to identify a function that satisfies the given argument types
>         You may need to add explicit typecasts

now return a timestamp with time zone and your function
take a timestamp without time zone.                 ^^^^^^^


Regards
Gaetano Mendola

Marc G. Fournier wrote:

>'k, this doesn't look right, but it could be that I'm overlooking
>something ...
>
>The function I created:
>
>CREATE FUNCTION month_trunc (timestamp without time zone) RETURNS timestamp without time zone
>    AS 'SELECT date_trunc(''month'', $1 )'
>    LANGUAGE sql IMMUTABLE;
>
>
>The query that fails:
>
>ams=# select * from traffic_logs where month_trunc(runtime) = month_trunc(now());
>ERROR:  Function month_trunc(timestamp with time zone) does not exist
>        Unable to identify a function that satisfies the given argument types
>        You may need to add explicit typecasts
>
>The query that succeeds:
>
>ams=# explain select * from traffic_logs where month_trunc(runtime) = '2003-10-01';
>                                        QUERY PLAN
>-------------------------------------------------------------------------------------------
> Index Scan using tl_month on traffic_logs  (cost=0.00..30751.90 rows=8211 width=36)
>   Index Cond: (month_trunc(runtime) = '2003-10-01 00:00:00'::timestamp without time zone)
>(2 rows)
>
>I haven't mis-spelt anything that I can see ... is this something that is
>known not to be doable?
>
>  
>
Try casting now() to timestamp without time zone?

cheers

andrew

On Mon, 10 Nov 2003, Gaetano Mendola wrote:

> Marc G. Fournier wrote:
>
> > 'k, this doesn't look right, but it could be that I'm overlooking
> > something ...
> >
> > The function I created:
> >
> > CREATE FUNCTION month_trunc (timestamp without time zone) RETURNS timestamp without time zone
> >     AS 'SELECT date_trunc(''month'', $1 )'
> >     LANGUAGE sql IMMUTABLE;
> >
> >
> > The query that fails:
> >
> > ams=# select * from traffic_logs where month_trunc(runtime) = month_trunc(now());
> > ERROR:  Function month_trunc(timestamp with time zone) does not exist
> >         Unable to identify a function that satisfies the given argument types
> >         You may need to add explicit typecasts
>
> now return a timestamp with time zone and your function
> take a timestamp without time zone.
>                   ^^^^^^^

d'oh, I knew I was mis-reading something there ... thanks