Something to remember... RAM is worthless unless it is being used. RDBMS's can
benefit lots from things like in memory caching.

Jason

Pavel Menshchikov wrote:

> Hello,
>
>
>>>Try to add DESC index on field_A: in FB indices are uni-directional.
>>>If field_A has a poor selectivity, add compound DESC index on
>>>(field_A, primary_key) instead of adding DESC index on field_A.
>
>
> d> I think What is strainge is that,
> d> They are same databases in MSSQL and firebird,
> d> with same tables, same indices, same data.
>
> d> but MSSQL uses memory as 10 times as Firebird uses.
>
> I can't tell anything about memory consuming with MSSQL: I guess it
> consumes as much memory as it wants (needs?). Probably, MSSQL uses
> memory to maintain groupping information in a different way as
> compared to FB...
>
> What about the performance in FB with your original SELECT MAX...
> after adding DESC index? And memory usage with FB?
>
>
>