On Wed, Oct 1, 2008 at 6:03 PM, Ann W. Harrison <aharrison@...> wrote:

> Timothy
>
>>>
>>>> I believe many applications can be made to work without reading the row
>>>> count in advance...
>>
>> Ok, ok.
>> I do not really have this problem, I was just saying what my expectations
>> would be.
>>
>> But does the engine not need this information internally during all sort
>> of
>> queries ?
>>
>
> Yes it does, and it uses approximately the heuristic I described -
> gets an estimate of the number of data pages in use and multiplies
> by the number of rows that fit on a page. Because it can read the
> pointer pages and see how many slots are in use, its estimate is
> better than you can get, but it's still a rough guess.
>
> Regards,
>
> Ann

Firebird really uses fixed-length records ?

so nRecCount = nPages * (nPageSize / nRecSize) ?

Are fixed-length records not a bad thing ?

Thank you,
Timothy Madden