While SQLite3 is extremely convenient for development and testing databases, and PostgreSQL has powerful Generalized Search Tree indexes and is very close to being enterprise-ready,
MySQL is the choice for many Web sites thanks to its excellent read performance, transparent support for large text and binary objects, and incredibly easy administration. Stored procedures, functions, triggers, and updateable views were added to MySQL in version 5, overcoming the largest technical objections to its deployment at many sites. MySQL also has a large, helpful user base, and some poster-child deployments including eBay, Yahoo, and Craigslist.
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