--- In firebird-support@yahoogroups.com, <MehtaY@...> wrote:

>
> Hi All,
>
> I am using firebird 2.0. The DB was at size 35.227 MB and then shink to
> 25 MB. I found that some data is lost. Does it has any size limit?
>
> If it has any size limit, how I can backup the data before loosing.
>
> Thanks in advance for the solution.

You are well over 29 Terabytes below the theoretical database size
limit of Firebird, and well over 49 GB below the theoretical table
size limit if your entire database consists of just a single table.

Firebird never hands space back to the OS. Instead, when records are
deleted and garbage collected, that space will be reused when required.

How are you measuring the database size? I don't think asynchronous
writes would cause the file size to drop, it is more likely to cause
the disk size to not increase when it should, but forced writes should
be on unless it is absolutely necessary to switch it off.

You should also know the Firebird 2 is not considered stable for
production release, and I get the impression from the fact you seem
unaware of gbak that you should be on the stable 1.5.3 version. Not
that I think that this is an issue in Firebird 2 though.

Adam