> DELETE FROM TABLE_EXAMPLE
> WHERE TABLE_EXAMPLE.ID IN (SELECT MAX(TABLE_EXAMPLE.ID)
> FROM TABLE_EXAMPLE
> GROUP BY FIELD1, FIELD2,
> FIELD3)
>
> If you have problems with performance of delete statement you should try
> convert it into a stored procedure.

Check this statement in firebird-support first! Firebird has one issue,
that might cause deleting ALL records from the table with this statement!

Roman