Oracle/SQL Couting multiple colums grouped by a common column -

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i'm yet oracle query. want do counting on multiple columns grouped common field. have half of done far. given following table

thing action -------------- t1  _a_ t1  _a_ t1  _b_ t2  _a_ t2  _b_

i have query

select    thing,     count(action) "a"   <table>   action = '_a_'  group thing

which results in

thing ---------- t1    2 t2    1

what see though this

thing b -------------- t1    2   1 t2    1   1

but i'm not how that. ideas?

thanks!

select thing,        count(case action when '_a_' 1 end) a,        count(case action when '_b_' 1 end) b <table> group thing

or sum(case action when '_a_' 1 else 0 end) if prefer


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