Let's say you have a table named table001 that is using the InnoDB engine. The show table status command can be used to see that the engine is InnoDB.

mysql -e "show table status \G"

Something like this should be returned.

  Name: table001
Engine: InnoDB

By default, a file named ibdata1 is used to store InnoDB data. Typically, this file is located in the /var/lib/mysql directory. Whatever you do, do not delete this file. Deleting this file will put you into a world of hurt.

This file is shared. If you have multiple InnoDB tables, each table will append events to the ibdata1 file.

~]# ls -l /var/lib/mysql
-rw-rw---- 1 mysql mysql 56140759040 Apr  8 21:40 ibdata1

The ibdata1 file can grow to be very large.

~]# du -hs /var/lib/mysql/*
53G     /var/lib/mysql/ibdata

Individual files for each table (.ibd)

If you want to have individual data files for each table, follow these steps.

1. Stop mySQL or MariaDB
2. Backup each database
3. Delete the "ib" files

rm -f /var/lib/mysql/ib*

4. Add the following directive to /etc/my.cnf

innodb_file_per_table=ON

5. Start mySQL or MariaDB
6. Import the databases

Now you should have individual ".ibd" files for each table, something like this.

/var/lib/mysql/table001.ibd
/var/lib/mysql/table002.ibd

Increasing the size of the ibdata file(s)

By default, the innodb_data_file_path directive in /etc/my.cnf defines the name of the file (ibdata1). In this example, the 10M:autoextend options means that the InnoDB tablespace will be extended by 10 MB, as needed, if the /var/lib/mysql has enough available space.

innodb_data_file_path=ibdata1:10M:autoextend

Or, multple ibdata files can be used.

innodb_data_file_path=/ibdata1/ibdata2:10M:autoextend

Optionally, max can be used to specify the maximum size of the ibdata1 file.

innodb_data_file_path=ibdata1:10M:autoextend:max:10G