Re: count & distinct

Andrea Aime wrote:
>
> Hi people. I would like to make a query that
> tells me how many distinct values there are
> in a column. Standard count doesn't seems
> to support a count distinct option.
> select distint count(*) of course doens't
> work (distinti clause is applied after the
> result are calculated). I've tried to define
> a view, but it didn't worked (
> create view distValues as select distinct ...
> but views doesn't support distinct clause)...
>
> Well, maybe I should create a new aggregate
> function, but before spending time on PGSQL
> guide I would like to know if someone can
> give me a fast tip... ;-)
> Thanks in advance
> Andrea
>
> PS: well, of course I can open a cursor on
> a "select distinct column from table" and then
> loop over the cursor couting how many values
> there are, but it seem a bit ugly...

SELECT field, count(*) FROM table GROUP BY field

With best regards, Max Vaschenko,
Nizhny Novgorod Information Networks.