From the objective of OSS-DB Exam Silver
- Operation and Management - Backup method
Sample Question
1.31
Choose the appropriate options for obtaining base backups to be used in Point-in-Time Recovery (PITR).
- Execute the pg_dumpall command.
- Execute the pg_basebackup command.
- Stop the database with pg_ctl stop, then create a physical copy of the database cluster with the tar command.
- Connect to database as administrator user in psql, select pg_start_backup ('label');After that, make a physical copy of the database cluster with the tar command.
- Connect to the database as an administrator user with psql and execute select pg_create_backup ('backup_file');
※This sample exam is different from those that appear in the actual OSS-DB Exam.
2019/03/04
Answer and Explanation
To create a base backup for use with PITR or streaming replication,
(1) Connect as an administrator user to the database and execute select pg_start_backup ()
(2) Create a physical copy of the entire database cluster using OS commands such as tar,
(3) Connect as an administrator user to the database and execute select pg_stop_backup ()
We will carry out the three steps. In PostgreSQL 9.1 and later, you can execute these three steps collectively and automatically by executing the pg_basebackup command.
It is a logical backup of the database that can be created with pg_dumpall, it can not be a base backup of PITR. The cold backup acquired after stopping the database with pg_ctl stop is also important for the operation management of the database, but it is not a base backup of PITR.
Therefore, the correct answers are B and D.