Subject Re: [firebird-support] Database was emptied no data in the tables - how this can happen ?
Author Ann W. Harrison
infoneto wrote:
> We had several cases where information in database was deleted and we where left with all the tables empty. the database file size however seems correct. The deletion was not done by us.
> We use firebird 2.0.3 on Windows XP
> 1. Is it possible that during backup - restore using gbak that we perform every night data will be lost ?

As Helen said, if you restore your backup using the -r option, Firebird
deletes the old database file, creates a new empty file, and stores the
definitions and data from the backup file in the new file. Why do you
backup and restore every night? Frequent backups are good, but you
should not need to restore them nearly that often.

> 2. When restoring is interrupted the database is left in such empty state ? if so why restoring is not like a transaction that unless successful the database will be left unchanged.

If you interrupt a restore, you'll get a completely empty database
unless you use the -o switch that commits after each table is restored.

> 3. During backup is it possible that the database will be changed (no access is performed during backup)

The backup doesn't change the database at all - other than doing
some garbage collection. The restore, on the other hand, creates
and populates a new database. As Helen said, if you

> 4. Can a corrupted backup be restored ?

No, a corrupted backup generally can't be restored. IBSurgeon
has tools that allow you to fix some corrupted backups.
> Is there a way to restore the database to it original state ?

IBSurgeon also has an "undelete" tool.

Good luck,