MySQL 5.5 Command Line Client SQL常用语句
MySQL 5.5 Command Line Client SQL常用语句
A.创建数据库、数据表
root登录MySQL
创建一个名称为demo的数据库
CREATE SCHEMA demo;
使用USE命令指定使用demo数据库
USE demo;
创建一个t_message表格,其中有id,name,email,msg等字段
CREATE TABLE t_message(
id INT NOT NULL AUTO_INCREMENT PRIMARY KEY,
name CHAR(20) NOT NULL,
email CHAR(40),
msg TEXT NOT NULL
);
设置id为AUTO_INCREMENT,表示由MySQL来管理字段的值,如果没有指定id的值,则会根据上一笔数据的id值自动递增;指定PRIMARY KEY可以指定字段设置主键。也可以像下面这样设置主键:
CREATE TABLE t_message(
id INT NOT NULL AUTO_INCREMENT,
name CHAR(20) NOT NULL,
email CHAR(40),
msg TEXT NOT NULL,
PRIMARY KEY(id)
);
删除数据表
DROP TABLE t_message;
删除整个数据库
DROP SCHEMA demo;
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