SQL problem with aggregate functions.

Hi the list !
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 ?
-- 
David BOURIAUD
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In a world without walls or fences, what use do we have 
for windows or gates ?
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ICQ#102562021