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From: Erland Sommarskog <esquel@sommarskog.se>
Newsgroups: comp.databases.ms-sqlserver
Subject: Re: Make a backup only if necessary
Date: Tue, 28 May 2024 20:11:54 +0200
Organization: Erland Sommarskog
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Anton Shepelev (anton.txt@g{oogle}mail.com) writes:
> I still fail, however, to understand why `first_lsn' changes
> for each subsequent diff. backup.  It is described as the
> "log sequence number of the first or oldest log record in
> the backup set." Since the last five diff. backups were
> generated with respect to the same full backup, I expected
> them to have the same first_lsn.  Why do they not?
> 

Because the backup itself is logged.