参考链接

[Storing sex (gender) in database——stackoverflow](https://stackoverflow.com/questions/4175878/storing-sex-gender-in-database)

ISO/IEC 5218——Wiki

性别在数据库怎样定义

> 1. **Int** - _aligned with Enum in code (1 = Male, 2 = Female, 3 = ...)_ > 2. **char(1)** - _Store __**m**__, __**f**__ or another single character identifier_ > 3. **Bit** _(boolean)_ - _is there an appropriate field name for this option?_ >

按照国际标准来设定的话，显然性别肯定不止一个。以下是国际标准中的定义(ISO/IEC 5218)

• 0 = Not known;
• 1 = Male;
• 2 = Female;
• 9 = Not applicable.

那么boolean肯定是不适用国际标准的，char类型在枚举中性能、存储上非常有优势，所以优先选择char类型作为性别存储。