MySQL – Where Does MySQL Store Data?

MySQL

Where does mysql store data? I found out (by using mysql>SELECT @@datadir ) that it's in var/lib/mysql – but that can't be it. I have a quite big database (4 GB) called 'bot', but all the files in the 'bot' subdirectory (var/lib/mysql/bot) have only 280KB. Where is the rest?

One more thing – 99% of the database's size is a text column in one of the tables – I know that mysql stores it in separate files, but does it create one file per record?

Best Answer

If you're using InnoDB and have a reasonably default configuration, tablespace data is in the ibdata files, you should have at least ibdata1 by default.

You may want to read up about its configuration:

https://dev.mysql.com/doc/refman/5.7/en/innodb-configuration.html

Specifically splitting it so that each table gets its own ibdata file:

https://dev.mysql.com/doc/refman/5.7/en/innodb-multiple-tablespaces.html

And there are some related questions:

Ibdata usage and Recommendations?

If you're not using InnoDB, disregard that :)

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