Mysql – Need for backing up MySQL databases information_schema, performance_schema, thesql and phptheadmin


I know it's not necessary to backup the information_schema database, but what about the following databases (besides the user-defined databases)?

  • performance_schema
  • mysql
  • phpmyadmin

(So, in case of problems, and we've to start from scratch (fresh MySQL-install), which databases do I've to place back)?)

Best Answer

  • performance_schema: Not necessary. It may contain performance metrics that are only good for the time you were using the instrumentation. It would serve no purpose to load collected metrics from the past into another MySQL instance or into the same MySQL instance at a much later time.

  • mysql : BE VERY CAREFUL HERE !!! If you backup mysql, you can only reload it into the same version of MySQL it came from. In particular, the mysql.user is neither forward nor backward compatible. See my old posts:

  • phpmyadmin : If you wish to reload a backup of phpmyadmin into the same MySQL instance it came from, that would be fine.