MySQL Storage Engines - page 3

What is a Storage Engine?

There are a number of ways you can specify the storage engine to use. The simplest method, if you have a preference for a engine type that fits most of your database needs to set the default engine type within the MySQL configuration file (using the option storage_engine or when starting the database server (by supplying the --default-storage-engine or --default-table-type options on the command line).

More flexibility is offered by allowing you specify the storage engine to use MySQL, the most obvious is to specify the engine type when creating the table:

CREATE TABLE mytable (id int, title char(20)) ENGINE = INNODB

You can also alter the storage engine used for an existing table:

ALTER TABLE mytable ENGINE = MyISAM

However, you should be careful when altering table types in this way as making a modification to a type that does not support the same indexes, field types or sizes may mean that you lose data. If you specify a storage engine that doesn't exist in the current database then a table of type MyISAM (the default) is created instead.