ubiquitous

One of the applications I inherited is a course registration system using the ubiquitous LAMP architecture (Linux, Apache, MySQL, PHP) and the default MyISAM table format. During peak usage (about 100 simultaneous users) some of the records added to the system were incorrectly linked with other records in related tables. The problem was that no locking was done on the database, leading to some SQL insert commands being executed out of order. While the MyISAM engine provides table locking to simulate transactions, that wasn't good enough for such a heavily used application. I needed the row-level locking and ACID transaction support of InnoDB. Here are the steps I took to convert a MySQL database from MyISAM to InnoDB: