Re: short-cutting if sum()>constant

In response to Ivan Sergio Borgonovo :
> Hi,
> 
> I'd like to know if
> 
> select sum(qty) from t where status=37;
> 
> is > constant.
> 
> qty is always >0.
> 
> Is there a way to skip examining further rows and return a result
> ASAP?

I think no.

But you can create a new table with 2 columns: status (primary key) and
a column for the sum of qty. And you need a TRIGGER: update this table
for every insert, update and delete on your table t.

Now you can ask _this_ new table if the sum(qty) > your constant, this
should work very fast.


Just an idea...


Andreas
-- 
Andreas Kretschmer
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