Creating an incremental backup

An incremental backup is a type of online backup. An incremental backup is a backup of the transaction log only and can only be used for recovery if you have run a full backup before running the incremental backup. Full backups can be interspersed with several incremental backups.

Prerequisites

You must have the BACKUP DATABASE and VALIDATE ANY OBJECT system privileges.

Context and remarks

The backup copies of the database file and transaction log file have the same names as the online versions of these files. For example, if you make a backup of the sample database, the backup copies are called demo.db and demo.log. When you repeat the backup statement, choose a new backup directory to avoid overwriting the backup copies.

For information about making a repeatable incremental backup command by renaming the backup copy of the transaction log, see Renaming the backup copy of the transaction log during a backup (SQL).

Task

Connect to the database.
Validate the database to ensure that it is not corrupt. You can use the Validation utility, the sa_validate stored procedure, or the VALIDATE DATABASE statement.
Make a backup of your transaction log, not your database file. For example, use the BACKUP statement.

Results

An incremental backup of your transaction log is created.

Example

The following statement creates an incremental backup of the database in the directory C:\temp\backup:

BACKUP DATABASE
DIRECTORY 'c:\\temp\\backup'
TRANSACTION LOG ONLY
TRANSACTION LOG TRUNCATE;

Creating an incremental backup

Task

See also