Re: short-cutting if sum()>constant

Does PG support CTE?
You can try it.

> In response to Ivan Sergio Borgonovo :
> > Развернуть 
> > 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
> 

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