Hi,

>> Can't you solve it another way? Like:
>>
>> DELETE FROM
>> ppm_mappings m2
>> WHERE
>> NOT SINGULAR(SELECT 1 FROM ppm_mappings m1 WHERE
>> m1.matrix_id = m2.matrix_id and
>> m1.product_id = m2.product_id and
>> m1.process_id = m2.process_id)
>
> If I understand the standard correctly, that should delete all records
> that have duplicates when the query starts. It won't, given the current
> state of Firebird, because we incorrectly execute the subselect for each
> iteration of the delete, so the last record with each set of values
> fails the "NOT SINGULAR" test.

I thought it was the intention to leave only 1 record from all the duplicates, but i could
misunderstood the question.

Regards,
Arno Brinkman
ABVisie

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