关于mysql中的int（m）

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关于
mysql
中的
int
（
m
）：
mysql
　数字类型的　
int(3)
或
int(1)
其中括号数字表示什么
.
官方有一段话：
 
Another
extension is supported by MySQL for optionally specifying the display width of
integer data types in parentheses following the base keyword for the type (for
example, INT(4)). This optional display width is used to display integer values
having a width less than the width specified for the column by left-padding
them with spaces.
所以说
m
可不是表示存贮大小的，他表示的当数据的宽度，要是数据的宽度小于
m
，就用空格左补充。
mysql
的
int
型是长整形，也就是
0~232
，也就是
4
个字节啦。