: In some distributions, the default storage engine is MyISAM, which is not transaction safe. Setting the default engine to a transactional engine such as InnoDB is, however, trivial. MySQL has a query cache that does simple string matching before the parser to see whether a query has been processed recently and rapidly returns the result to the client application if it has, without the need to do any of the traditional database work. This is of considerable value to many read-mostly workloads. Cached queries are removed whenever any table involved in the query is changed so its usefulness declines as the rate of data changes increases. The query cache runs on a single thread and must consider each select, so it may eventually become a performance bottleneck at some point beyond 8 cores, but that's not usually the case. It can be turned off easily to check this and to see whether its small overhead is worthwhile for the particular workload. MySQL also supports network protocol-level compression which is an option that can be turned on by the client if the server allows it. This compresses everything to and from the server. * LikeEscape:[http://dev.mysql.com/doc/refman/5.0/en/string-comparison-functions.html#operator_like]