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CHAPTER 28 • MYSQL STORAGE ENGINES AND DATA TYPESwww.it-ebooks.infocorrectly carried out to ensure data consistency. As you might imagine, such capabilities require someoverhead due to the additional features that must be incorporated into the table.■ Note MySQL’s transactional features are introduced in Chapter 37.Some tables aren’t intended to store any long-term information at all, and are actually created andmaintained entirely in a server’s RAM or in a special temporary file to ensure a high degree ofperformance at the risk of high volatility. Other tables exist solely to ease the maintenance of and accessto a collection of identical tables, offering a single interface for simultaneously interacting with all ofthem. Still other special purposes exist, but the point has been made: MySQL supports many types oftables, also known as storage engines, each with its own specific purpose, advantages, anddisadvantages. This section introduces MySQL’s supported storage engines, outlining the purpose,advantages, and disadvantages of each. Rather than introduce the storage engines in alphabetical order,it seems most prudent to present them beginning with those most commonly used, MyISAM, andconcluding with those intended for more specific purposes:• MyISAM• IBMDB2I• InnoDB• MEMORY• MERGE• FEDERATED• ARCHIVE• CSV• EXAMPLE• BLACKHOLEFollowing the presentation of the storage engines is an FAQ section to address other issuesregarding storage engines.MyISAMMyISAM became MySQL’s default storage engine as of version 3.23. 1 It resolves a number of deficienciessuffered by its predecessor (ISAM). For starters, MyISAM tables are operating system independent,meaning that you can easily port them from a Windows server to a Linux server. In addition, MyISAMtables are typically capable of storing more data, but at a cost of less storage space than their older1 However, on Windows platforms the Windows Essentials installer designates InnoDB as the defaulttable type.528