MySQL数据库设计之各种INTEGER类型最佳实践_MySQL
最佳实践
UNSIGNED 只能存储非负整数SIGNED 可以存储正整数、0、负整数对于总是正整数的存储(比如主键)的最佳实践是 UNSIGNED，因为这时它占用和 SIGNED 一样的存储空间，但取值范围多出一倍BOOL、BOOLEAN 只不过是 TINYINT(1) 的另外一种写法而已TINYINT(1)、BOOL、BOOLEAN 所占用的存储空间和 TINYINT 一样，都是一个字节，而不是一位TINYINT(1) 所能存储的值的范围和 TINYINT 一样，都是 -128 到 127TINYINT(1) 只是在显示的时候作为一个位进行输出而已
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