数值类型

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  1. age tinyint unsigned;
  2. score double(4,1);

字符串类型

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char(10);         --性能相对较高
varchar(10);

username varchar(50);        --用户名
gender char(1);                    --性别

日期时间类型

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birthday date;

案例

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create table emp(
  id int comment '编号',
  workno varchar(10) comment '员工工号',
  name varchar(10) comment '姓名',
  gender char(1) comment '性别',
  age tinyint unsigned comment '年龄',
  idcard char(18) comment '身份证号',
  entrytime date comment '入职时间'
) comment '员工信息表';

运行结果：


mysql> show tables;
+------------------+
| Tables_in_ithema |
+------------------+
| emp              |
| user_id          |
+------------------+
2 rows in set (0.01 sec)

mysql> desc emp;
+-----------+------------------+------+-----+---------+-------+
| Field     | Type             | Null | Key | Default | Extra |
+-----------+------------------+------+-----+---------+-------+
| id        | int              | YES  |     | NULL    |       |
| workno    | varchar(10)      | YES  |     | NULL    |       |
| name      | varchar(10)      | YES  |     | NULL    |       |
| gender    | char(1)          | YES  |     | NULL    |       |
| age       | tinyint unsigned | YES  |     | NULL    |       |
| idcard    | char(18)         | YES  |     | NULL    |       |
| entrytime | date             | YES  |     | NULL    |       |
+-----------+------------------+------+-----+---------+-------+
7 rows in set (0.01 sec)