Try
SELECT FIRST 1 KEYFIELD
FROM SALESDATA
WHERE (PRODUCT = :someproduct) AND
(TRANSACTION_DATE >= :somedate)

It's better way IMHO.
Ramil

--- In IBObjects@yahoogroups.com, "paulfilmer" <pfilmer@b...> wrote:
> Hi All
>
> Often I need to test whether a record exists. For example, checking
> whether a product has been sold in the last X days may have SQL that
> looks like:
>
> SELECT KEYFIELD
> FROM SALESDATA
> WHERE (PRODUCT = :someproduct) AND
> (TRANSACTION_DATE >= :somedate)
>
> Assume there could be 1000's of matching records, but I just want to
> know if at least one exists. The SQL could also perform joins across
> tables. If cursor is in a tight loop in the code (eg checking
> 10,000's of products) then I want to optimise such code for best
> response.
>
> The best way I have found to do this is a TIB_Cursor, setting
MaxRows
> set to 1. I could also use 'SELECT COUNT(*)' but that would have to
> get all records... I just want to know if at least one exists. As
far
> as I know you can't use an 'IF EXISTS()' in this situation.
>
> Can anyone suggest a faster way to do such a query using IBO
> components? I don't know much about stored procedures. Do you think
> that could help?
>
> Thanks very much in advance!
>
> Paul.