Using extended keys with InnoDB and XtraDB

When creating an execution plan for a query, the MariaDB optimizer makes a cost-based decision about whether or not to use one or more indexes instead of reading through a table row-by-row. Indexes are often, but not always the faster choice. The extended key's optimization improves the index lookups for InnoDB and XtraDB tables.

How to do it...

1. Launch the mysql command-line client application and connect it to our MariaDB server as the root user or as a user with the SUPER privilege.

2. Enable the extended keys optimization with the following command:

   SET GLOBAL optimizer_switch='extended_keys=on';
   

3. Add the following code to our my.cnf or my.ini file (or to an existing [mysqld] section):

   [mysqld]

4. optimizer_switch = 'extended_keys=on' verifies that extended_keys is set to on with the following command:

   SHOW VARIABLES LIKE 'optimizer_switch'\G
   

How it works...

In this recipe, we turn on the extended_keys optimization globally for the running server and we...