Re: Weird type selection choice - Mailing list pgsql-hackers

From Peter Eisentraut
Subject Re: Weird type selection choice
Date
Msg-id 200711071640.36561.peter_e@gmx.net
Whole thread Raw
In response to Re: Weird type selection choice  (Heikki Linnakangas <heikki@enterprisedb.com>)
Responses Re: Weird type selection choice  (Tom Lane <tgl@sss.pgh.pa.us>)
Re: Weird type selection choice  (Alvaro Herrera <alvherre@commandprompt.com>)
List pgsql-hackers
Am Mittwoch, 7. November 2007 schrieb Heikki Linnakangas:
> Peter Eisentraut wrote:
> > I wrote:
> >> I noticed this problem in 8.2 and 8.3:
> >>
> >> pei=# select mod( trunc( 1 ), 2 );
> >> ERROR:  42883: function mod(double precision, integer) does not exist
> >> LINE 1: select mod( trunc( 1 ), 2 );
> >>                ^
> >
> > I suppose there will be little interest in including the obvious
> > solution, namely
> >
> > CREATE FUNCTION pg_catalog.trunc(int) RETURNS int AS $$ SELECT $1; $$
> > LANGUAGE SQL STRICT IMMUTABLE;
>
> It does sound totally useless...
>
> Why would you run a query like that in the first place? It seems like a
> useless query as it is. Is there a bigger story behind it?

The "1" is substituted from somewhere else.  If the value happens to be, say, 
1.5, it works, but not with 1 or 2.

-- 
Peter Eisentraut
http://developer.postgresql.org/~petere/


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