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mysql workbench建表时PK,NN,UQ,BIN,UN,ZF,AI

时间:2015-05-19 13:10:29      阅读:268      评论:0      收藏:0      [点我收藏+]

标签:mysql

[intrinsic column flags] (基本字段类型标识)

- PK: primary key (column is part of a pk) 主键
- NN: not null (column is nullable) 非空
- UQ: unique (column is part of a unique key) 唯一
- AI: auto increment (the column is auto incremented when rows are inserted) 自增

[additional data type flags, depend on used data type] 扩展数据类型标记
- BIN: binary (if dt is a blob or similar, this indicates that is binary data, rather than text) 二进制(比text更大的二进制数据)
- UN: unsigned (for integer types, see docs: “10.2. Numeric Types”) 整数
- ZF: zero fill (rather a display related flag, see docs: “10.2. Numeric Types”)值中最有意义的字节总为0,并且不保存。 
 
ps: ZF个人理解指的是带有小数占位符的数据相当于金额类型的数据。

mysql workbench建表时PK,NN,UQ,BIN,UN,ZF,AI

标签:mysql

原文地址:http://blog.csdn.net/dingxl555/article/details/45842127

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