Re: SQL problem with aggregate functions.

I would suggest something like

select sum(case when f1 = 'D' then 1 else 0 end) as D_COUNT,
sum(case when f1 = 'R' then 1 else 0 end) as R_COUNT,
sum(case when f1 = 'X' then 1 else 0 end) as X_COUNT
from tab
where f1 in ('D','R','X')

Not sure what the "field group" represents.

HTH,
Loyd

On Thu, 11 Jul 2002 10:37:40 METDST, Christoph Haller <ch(at)rodos(dot)fzk(dot)de> wrote:

>>
>> I've got a table in which there is a field that can have one amongst 3
>> possible values : D, R, X. Is it possible to get in one query the count of
>> this different values.Please, note that I don't want to have a querry like
>> this :
>> "select count (*) from tab group by f1;", cause i want to get all the possible
>> count values in one row (these data are already grouped on another field).
>> To give a more accurate example, here is what I want to retrieve :
>>
>> Field group | count of D | count of R | count of X.
>>
>> Any clues ?
>> --
>What about something like
>
>
>SELECT SUM(f1_d) AS count_d,
> SUM(f1_r) AS count_r,
> SUM(f1_x) AS count_x
>FROM (
> SELECT CASE WHEN f1 = 'D' THEN 1 ELSE 0 END AS f1_d,
> CASE WHEN f1 = 'R' THEN 1 ELSE 0 END AS f1_r,
> CASE WHEN f1 = 'X' THEN 1 ELSE 0 END AS f1_x
> FROM tab ) AS foo ;
>
>Regards, Christoph
>
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