What is InnoDB and MyISAM in MySQL?

Question

What is InnoDB and MyISAM in MySQL ?

Answer 1

Have a look at

InnoDB and MyISAM

InnoDB is a storage engine for MySQL, included as standard in all current binaries distributed by MySQL AB. Its main enhancement over other storage engines available for use with MySQL is ACID-compliant transaction support

MyISAM is the default storage engine for the MySQL relational database management system versions prior to 5.5 1. It is based on the older ISAM code but has many useful extensions. The major deficiency of MyISAM is the absence of transactions support. Versions of MySQL 5.5 and greater have switched to the InnoDB engine to ensure referential integrity constraints, and higher concurrency.

Answer 2

I wanted to add that having ability to specify a specific storage engine per table is one of the key strengths of MySQL (besides easy of use and good performance with no tweaking). For all operations where transactions are needed, just stick with InnoDB. However, MyISAM can really speed things up when transactions are not needed in certain situations - and requires less disk space and RAM compared to InnoDB.

That said, InnoDB is getting better all the time:

InnoDB 1.1 Performance and Scalability Enhancements