Re: count( only if true)

El Mié 12 Oct 2005 15:42, peter pilsl escribió:
> the count-aggreate counts every expression that does not evaluate to null.
>
> I would like to have a count that counts all values that are true.
>
> Do I really need to make a count( case when expression then 't' else
> null) to implement this?

I'm not sure what exactly it is you want, but check this:

SELECT count(*) FROM tab WHERE expresion

There you get a count of tuples that satisfy the expresion. What NULL values
are you talking about? Can you hand an example?

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