Hi, Thanks for your suggestion.

The PLAN clause is automatically generated by IBO.
This case seems that DESC index must be added...

>VARCHAR(100): 0.51 - 0.60(s)
>VARCHAR(150): 0.78 - 0.84(s)
>VARCHAR(160): 0.79 - 0.86(s)

Those results are very fast, i have expectation...

--
Regards,
Minoru


Alexandre Benson Smith wrote:

>
>Measure the time of a fetch all...
>
>First plan will be fast to retrieve the first rows...
>
>An ASC index could not be used to do a indexed retrieval (Index Walking)
>for a DESC order by clause.
>
>No FB version would use a plan like
>
>PLAN (Test ORDER IDX01)
>
>
>for
>
>SELECT * FROM Test
>ORDER BY V DESC
>
>
>without a DESC index on test.v
>
>
>see you !
>
>--
>Alexandre Benson Smith
>Development
>THOR Software e Comercial Ltda
>Santo Andre - Sao Paulo - Brazil
>www.thorsoftware.com.br