>your trick of "sum( iff( ) )" as a column works exactly how i want.  geni us.
>
>i knew i needed to join my results query on the group-by year query.  just 
>didn't know how to write the counters... the sum( if() ) does it.
>
>i have multiple tables i want to perform this on and realize now that i can't 
>combine them all; it will be one query per table that as the counts.  but that 
>makes perfect sense to me now too.

Actually, sometimes you can do several counts within one SQL, but then you need 
to change things slightly:

count(distinct iif(<somecondition>, <sometable>.<PrimaryKey>, NULL))

and you might need to use LEFT JOIN rather than (INNER) JOIN.

Having a couple of such counts within a query are sometimes useful, but if you 
mix too much unrelated stuff within the same query, you may end up with a 
complex query that works perfectly, but that is completely unreadable.

Set

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