You can do it, but it will be slower than you might expect.

use invoice in 0 order tag cmpfk
use company in 0
select company
set relation to cmppk into invoices
set filter to invoice.amount > 0

This will show companies with invoice amounts > 0.

>I need to be able to filter a table with respect to data in another table.
>
>For example, as in the SELECT...FROM [table] LEFT OUTER JOIN [table2] WHERE [filtercondition]...this would dump the matching resuts into another cursor.
>
>I need that the original file [table] be filtered to the matching records of the search. I want to work with the original table!
>
>Is this possible?
>
>Thanks in advance!
>
>John