Hi Rohit Coder,

welcome to Firebird!

> 1. Which is the recommended data file structure: `Single file` or `Multiple files`?

I'll pass on this one. I may give wrong information.

> 2. What is the table and data file max-size for version 2.5?

Ditto.

> 3. What are the common scenarios of a Firebird data file getting corrupt? In case of a single-file structure, I guess no other files need to be backed up?

Some common backup scenarios are detailed in the gbak manual which you
can find online here as HTML -
http://www.firebirdsql.org/file/documentation/reference_manuals/user_manuals/html/gbak.html
or here as a pdf -
http://www.firebirdsql.org/file/documentation/reference_manuals/user_manuals/Firebird-gbak.pdf.

The specific chapter you want is at
http://www.firebirdsql.org/file/documentation/reference_manuals/user_manuals/html/gbak-recipies.html
where various recipies for diffrent backups and restores can be found.
Also there is information on why you shouldn't just 'cp' the database
file(s) and call that a backup!


There is also a manual for the nbackup tool at
http://www.firebirdsql.org/file/documentation/reference_manuals/user_manuals/html/nbackup.html
and also at
http://www.firebirdsql.org/file/documentation/reference_manuals/user_manuals/Firebird-nbackup.pdf.

There may be something in the above that answers your query.

HTH

Cheers,
Norm.

--
Norman Dunbar
Dunbar IT Consultants Ltd

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