Incremental backup and restore operations can be performed from any SQL client by executing the eXtremeSQL extensions BACKUP , VERIFY and RESTORE. (Also note that file backup can be performed for persistent databases by calling SQL function
The BACKUP statement must specify the backup type as one of the following:
- FULL backup (snapshot), which creates a backup record for the entire database,
- INCREMENTAL (partial), which records only the database modifications since the previous backup, or
- AUTO which creates a FULL or INCREMENTAL backup record depending on the content of the backup file: If there is no snapshot in the file yet the backup process will create one; otherwise a partial backup record is created.
The statement and can also specify an optional label. For example:BACKUP 'SimpleDb_backup' FULL 'Initial full backup' or BACKUP 'SimpleDb_backup' INCREMENTAL 'Backup July 15, 2016' or BACKUP 'SimpleDb_backup' AUTO 'Automatic backup'
Note that a FULL backup must be done at least once before an INCREMENTAL backup can be done successfully.
RESTORE a backup
To restore the database the RESTORE statement specifies the backup file and an optional label (to restore the database contents up to that label only). For example:RESTORE 'SimpleDb_backup' TO 'Backup July 15, 2016'
List the backup contents
The SELECT statement can be used to list the contents of a backup file. For example:SELECT * FROM BACKUP 'SimpleDb_backup'
VERIFY a backup
The VERIFY statement can be used to verify that a backup file will produce a successfully restored database. For example:VERIFY 'SimpleDb_backup' LABEL 'Backup July 15, 2016'