摘要： MySQL has a few storage types that use individual bits within a value to store datacompactly. All of these types are technically string types, regardless of the underlyingstorage format and manipulati... 阅读全文

摘要： String TypesMySQL supports quite a few string data types, with many variations on each. Thesedata types changed greatly in versions 4.1 and 5.0, which makes them even morecomplicated. Since MySQL 4.1,... 阅读全文

摘要： You should define fields as NOT NULL whenever you can. A lot of tables includenullable columns even when the application does not need to store NULL (theabsence of a value), merely because it’s ... 阅读全文