数据库之扫盲常用字段属性

Others 2021-11-28 21:40:20 views: null

数据库中字段属性（重点）

  • Unsigned
    • 无符号的整数
    • 声明了该列不能声明为负值，否则变为0
  • zerofill
    • 0填充的
    • 不足位数，使用0来填充
  • 自增
    • 自动增加，必须是整数
    • 可以自定义自增的起始值和步长
  • 非空 Not Null
    • 假设设置为not null，如果不给它赋值，就会报错
    • Null,如果不填值，就是默认Null

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Origin blog.csdn.net/weixin_47088026/article/details/110249150
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