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Storage Engine Breakdown


The following diagram represents a simplified view of the MySQL server and its interaction with the storage engines.


The following properties are storage engine dependant:


• Storage Medium – Each table uses its own method of storing the data it contains.


• Transactional Capabilities – Certain storage engines handle transactional processing which
ensures that integrity of a database is maintained during the processing of multiple SQL
statements.



• Locking – Each storage engines handles the processes of the synchronization mechanism for enforcing limits on access to a resource in an environment where there are many threads of
execution.


• Backup and Recovery – Based on the storage medium used, the backup of the table data and the recovery of that data can be distinct.


• Optimization – There are specific issues associated with each storage engine for the optimization of the storage of the data and retrieval of the data through the MySQL server.


• Special Features – There are a number of features that exist only in certain engine types to
include full-text search, referential integrity and the ability to handle spatial data. Most of the MySQL server operates in the same way no matter what storage engine is used: all the usual
SQL commands are independent of the storage engine. Naturally, the optimizer may need to make different choices depending on the storage engine, but this is all handled through a standardized interface (API) which each storage engine supports.
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