Re: Weird type selection choice

Peter Eisentraut wrote:
> 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.

Maybe as a workaround these are useful:

alvherre=# select mod( trunc( 1.0 ), 2 );
mod
-----
1
(1 fila)

alvherre=# select mod( trunc( 1::numeric ), 2 );
mod
-----
1
(1 fila)

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