Hi

> Thanks a lot for your long answer.
>
> Well, about backingup and restoring, the reason is that when we perform
> that its is made a kind of "cleaning" in the DB, am I right?
>
> My user makes lots of lots of INSERT and DELETEs, so after a while the
> DB gets slower.
>
> That's the reason, actually right now I have already in my application
> the procedure of creating backup using GBACK.
>
> So I wanted to do the oposite with all connections closed.

No.
You must use buckup and restore only manualy. For automatic garbage collection (sweeping in Firebird term) you can use gfix.
Example:
/opt/firebird/bin/gfix -sweep -user sysdba -password masterkey /opt/firebird/db/my_db.fdb

WBR Eugeney Putilin.