I want to get a list of all sales people who have non-zero amounts:

Select Sales.Person From Sales ;
	WHERE Sales.Item = theItem ;
	AND Sales.amount <> 0.00 ;
	AND Sales.fk_period In (Select periodV.cid From periodV) ;
	GROUP By Sales.Person ;
	Into Cursor doamt

Most of the records in this large table have zero amounts. As this is done many times, I wonder if there is a way to do this more efficiently?

Also, the period range tends to remain the same for most queries. Is it possible to get the values from an array, something like:

AND Sales.fk_period In Array aPeriod ;

(except that doesn't work - is it possible?)

Any suggestions on how to improve this SQL are welcome.

Cyril