Gbase 8C backup control function (II)

pg_start_backup(label text [, fast boolean ])

describe ： Start online backup .（ Administrator role or replicated role is required ）

return type ：text

remarks ：pg_start_backup Accept a user-defined backup label （ Usually, this is the name of the location where the backup dump file is stored ）. This function is directed to GBase 8c Write a backup label file to the data directory of , Then return the starting position of the backed up transaction log in the form of text .

 gbase=# SELECT pg_start_backup('label_goes_here');

pg_start_backup

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(1 row)

pg_stop_backup()

describe ： Complete the online backup .（ Administrator role or replicated role is required ）

return type ：text

remarks ：pg_stop_backup Delete pg_start_backup Created label file , And create a backup history file in the transaction log archive . This historical file contains giving pg_start_backup The label of 、 The starting and ending positions of the backup transaction log 、 Start and end time of backup . The return value is the end position of the backup transaction log . After calculating the stop position , The insertion point of the current transaction log will automatically advance to the next transaction log file , such , The finished transaction log file can be archived immediately to complete the backup .

pg_switch_xlog()

describe ： Switch to a new transaction log file .（ Administrator role is required ）

return type ：text

remarks ：pg_switch_xlog Move to the next transaction log file , To allow the current log file to be archived （ Assume continuous archiving ）. The return value is the end position of the transaction log of the just completed transaction log file +1. If there is no active transaction log since the last transaction log switch , be pg_switch_xlog Do nothing , Directly return to the starting position of the current transaction log file .