问题描述
我只是想知道为什么范围是用我的sql数据类型给定的.我定义了一个字段名称为"id"且数据类型为"int(2)"的表.我将值作为"123456"插入到字段"id"中.接受并存储了该值.那么给出范围的用途是什么.
Just I wonder why the range is given with the my sql data types. I define a table with a field name "id" and the data type is "int(2)". I inserted the value to the field "id" as "123456".This is accepted and stored. So what is the use of giving the range.
谢谢.
推荐答案
对于INT和其他仅指定显示宽度的数字类型.
For INT and other numeric types that attribute only specifies the display width.
请参见数值类型属性. MySQL文档:
See Numeric Type Attributes in the MySQL documentation:
显示宽度不受限制 可以存储的值的范围 在列中.也没有防止 值比列显示宽 宽度无法正确显示. 例如，指定为 SMALLINT(3)具有通常的SMALLINT 范围-32768至32767，以及值 超出三个允许的范围 数字使用完整显示 超过三位数.
The display width does not constrain the range of values that can be stored in the column. Nor does it prevent values wider than the column display width from being displayed correctly. For example, a column specified as SMALLINT(3) has the usual SMALLINT range of -32768 to 32767, and values outside the range permitted by three digits are displayed in full using more than three digits.
这篇关于"int"与"int"之间的区别是:和"int(2)"我的SQL中的数据类型的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持！