| From: | Bruce Momjian <pgman(at)candle(dot)pha(dot)pa(dot)us> |
|---|---|
| To: | Joseph Shraibman <jks(at)selectacast(dot)net> |
| Cc: | "pgsql-sql(at)postgresql(dot)org" <pgsql-sql(at)postgresql(dot)org> |
| Subject: | Re: counting distinct values |
| Date: | 2000-06-08 00:15:58 |
| Message-ID: | 200006080015.UAA04389@candle.pha.pa.us |
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| Thread: | |
| Lists: | pgsql-sql |
> 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;
--
Bruce Momjian | http://www.op.net/~candle
pgman(at)candle(dot)pha(dot)pa(dot)us | (610) 853-3000
+ If your life is a hard drive, | 830 Blythe Avenue
+ Christ can be your backup. | Drexel Hill, Pennsylvania 19026
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