I'm wondering about the topic of moving all MyISAM tables to InnoDB in RDS. Mostly because I have this annoying warning every day in the RDS console. One thing is pretty clear, the tables of the customer applications must be altered to InnoDB (if possible). No question about that. But what worries my is the "system" tables. If I run this query:
SELECT TABLE_SCHEMA, TABLE_NAME, ENGINE FROM INFORMATION_SCHEMA.TABLES WHERE ENGINE = 'MyISAM'
I get lot of tables with MyISAm tables that are not from the customer database but the MySQL itself, for example:
information_schema | COLUMNS | MyISAM | information_schema | EVENTS | MyISAM |
Let me call it "system tables".
It is kind of mandatory to also ALTER this "system tables" to InnoDB? I did not found any specific of this tables, and the warning message of RDS is not clear about that:
DB Instance db-byhours-56 contains MyISAM tables that have not been migrated to InnoDB. These tables can impact your ability to perform point-in-time restores. Consider converting these tables to InnoDB. Please refer to http://docs.aws.amazon.com/AmazonRDS/latest/UserGuide/Overview.BackingUpAndRestoringAmazonRDSInstances.html#Overview.BackupDeviceRestrictions
Any ideas or comments?
question bonus: what about other kind of engine like MEMORY? I have some customer with few tables like that engine. Can be this engine also a problem to get good snapshots?