Re: count function alternative in postgres

Quoth junaidmalik14(at)gmail(dot)com (junaidmalik14):
>
> Is there any alternative of mysql function COUNT(DISTINCT expr,[expr...]) in
> postgres. We get error if we
>
> write count like this count(distinct profile.id, profile.name, profile.age)
> but it works well in mysql.

Pg does support COUNT(DISTINCT ), but only for a single column. The best
I can come up with for multiple columns is

select count(distinct profile.tuple) from
(select (id, name, age) as tuple from profile)
as profile;

or alternatively

select count(*) from
(select distinct (id, name, age) as tuple from profile)
as profile;

Ben