Re: counting distinct values

> Using the example from
> http://www.postgresql.org/docs/aw_pgsql_book/node59.html, what would I
> do if I wanted to know the number of different cities where I had a
> friend in each state?  select count(city) group by state; would not work
> because if you had two friends in the same city it would be counted
> twice.
> 

How about?
select city, state, count(*) group by state, city;


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