Coral,

When Firebird needs more space it requests it from the OS. When you
delete the records, they are still there until no transaction is
interested in them and the garbage collection is run. The garbage
collection process flags the pages as free to be used again, but does
not hand the space back to the OS. This would be a slow and complex
operation which would end up fragmenting your file system like crazy!
Instead, Firebird will reuse that space again when it next needs it.

A Backup Restore cycle will obviously remove this entirely, but it
will grow again once you store that much data again.

On a side note, please do not use the reply button when posting a new
topic. Even though you changed the subject, it does mess up some
newsreaders, and some people may miss your message.

If you are using the web interface, then click post instead of reply.
If you are using an email client, then create a new message instead
of hitting reply.

Adam








--- In firebird-support@yahoogroups.com, "Coral Johnson"
<coral.johnson@...> wrote:

>
> We're developing a new database using Firebird. The database size

has been

> sitting at 8 mb for over a month. One day last week it increased

to 44 mb.

> We have been doing a lot of changes, both to the structure and to

the data,

> over the whole period, so I don't know why it suddenly increased so
> dramatically. We have now deleted all the data and want to

decrease the

> database size again. How can we do that?
>
> Regards Coral