Re: More on unique vs distinct

On Mon, 2006-11-20 at 19:46 -0300, Rodrigo Gonzalez wrote:
> Not 100% sure....
>
> select count(*) from (select distinct source_id from obis_sources) t

SELECT count(source_id) FROM obis_sources GROUP BY source_id ?

Joshua D. Drake

>
> Wm.A.Stafford wrote:
> > I guess I should have been a bit more specific. Here is an example of
> > the type of query I'm finding in the Oracle app and the results of my
> > attempt to find a PostgreSQL equivalent.
> >
> > select count(unique 'source_id') from obis_sources;
> > pgAdmin III query responds:
> > ERROR: syntax error at or near "'source_id'" at character 23
> >
> > select count(distinct 'source_id') from obis_sources;
> > pgAdmin III query responds:
> > ERROR: could not identify an equality operator for type "unknown"
> >
> > Thanks for all the help,
> > -=bill
> >
> >
> >
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