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During
my days as a DBA, I frequently received backup files from my
manager, with instructions to restore the contents. Here's what I
usually do to get a handle on things:
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Run
RESTORE
LABELONLY on the
file
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The
information provided tells me if the backup file is the only one in
a backup set, or if the backup file is part of a backup set. The
FamilyCount
and
FamilySequenceNumber
columns
provide this information. Recall that a backup may be spread across
multiple files. In such situations, you would need all the files in
order to restore the database successfully.
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Run
RESTORE
HEADERONLY on the
file
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the
number of backups that are contained in the file. A backup file may
contain multiple backup sets.
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the
backup type, whether if it's a full database backup, differential,
log etc.
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the
name of the database that was backed up.
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Run
RESTORE
FILELISTONLY on the
file
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I
would only run this on a full database backup. Running this tells
me the number of files that makes up the database, and the size of
each file. This allows me to know quickly if I have enough disk
space to restore the database.
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Can't
we tell the size of the database from the backup file size? No, if:
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the
backup file contains multiple backup sets
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the
database's tranaction log file contains mostly truncated data
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In
summary, there is a wealth of information you can retrieve from a
backup file, using the RESTORE
LABELONLY,
RESTORE
HEADERONLY and
RESTORE
FILELISTONLY commands.
See the Books Online documentation for these commands for more
details.
Document history
| 6/27/2008 | Initial release. |
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