Subject Re: DB corruption, was OT: Survey about database corruption..
Author Helen Borrie
At 06:13 PM 11/07/2003 +0800, you wrote:

>Helen Borrie <helebor@...> wrote (regarding the path string bug) :
>Don't use InterBase. (The problem is fixed in Firebird: if anyone tries,
>access is denied). The bug and the fix are described on Page 32 of the v.1
>release notes.

Jinyang wrote:

>I am sorry to say that Database had been corrupted by using
>Firebird- this problem can be avoid by using the
>Firebird- or other version?

The only thing it is possible to say with certainty is that, if your client
was connected to a Firebird 1 server, the path string bug did NOT cause
your corruption ...You'll need to move on and examine other causes.

>Other question:There are some phrase like "Page 3434 is an orphan" in
>Interbase.log.What means this?

I think this error indicates that your transaction inventory page is
corrupt (but Ann will set you straight about this). This used to be likely
to happen when you hit the operating system file size limit - the server
would start overwriting the beginning of the database file, where the
database accounting pages live.

At some point I recall it was made so that a fatal exception would be
raised if a write was attempted past the o/s filesize limit, but I may have
dreamt this; or it may be a v.1.5 feature.

You need to know the filesize limit on your server's operating system.
Assume it is 2Gb until you find out for sure. It's a part of your regular
housekeeping that you inspect the growth of the database file and split the
database into multiple files well before it approaches the limit. On
FAT32, for example, you should split the file up when it gets to around 1.7 Gb.

>Why have this log?

The log reports back on server-level, filesystem and network errors. It's
good practice to keep an eye on the log even when all is going well, just
to check whether there are unusual things happening.