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Backup And Recovery Functions In Postgresql

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Backup Control Functions:-
These functions cannot be executed during recovery (except pg_is_in_backup, pg_backup_start_time and pg_xlog_location_diff).
pg_create_restore_point(name text):- Create a named point for performing restore (restricted to superusers)
pg_current_xlog_insert_location():- Get current transaction log insert location
pg_current_xlog_location():- Get current transaction log write location
pg_start_backup(labeltext [, fast boolean ]):- Prepare for performing on-line backup (restricted to superusers or replication roles)
pg_stop_backup():- Finish performing on-line backup (restricted to superusers or replication roles)
pg_is_in_backup():- True if an on-line exclusive backup is still in progress.
pg_backup_start_time():- Get start time of an on-line exclusive backup in progress.
pg_switch_xlog():- Force switch to a new transaction log file (restricted to superusers)
pg_xlogfile_name(location text):- Convert transaction log location string to file name
pg_xlogfile_name_offset(location text):- Convert transaction log location string to file name and decimal byte offset within file
pg_xlog_location_diff(location text, location text):- Calculate the difference between two transaction log locations

Recovery Control Functions:-
The functions shows provide information about the current status of the standby. These functions may be executed both during recovery and in normal running.
pg_is_xlog_replay_paused():- True if recovery is paused.
pg_xlog_replay_pause():- Pauses recovery immediately.
pg_xlog_replay_resume():- Restarts recovery if it was paused.




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