马哥学习笔记五MYSQL初步
1.mysql
-u USERNAME
-p
-h MYSQL_SERVER
linux:socket
windows:memory
2.交互式模式中的命令类别
客户端命令
服务器端命令
必须使用语句结束符,默认为封号
3.关系数据库对象:
表
索引
视图
约束
存储过程
存储函数
触发器
游标
用户
权限
事务
4.常用命令
DDL:数据库定义语言
create,alter,drop
DML:数据库管理语言
insert,update,delete
DCL:数据库控制语言
grant,revoke
创建数据库
create database db_name;
create database [if not exists] db_name;
删除数据库
drop database [if exists] db_name;
创建表
create table tb_name(col1,col2,...);
查看库中表:show tables from db_name;
查看表结构:desc tb_name;
删除表:drop table tb_name;
修改表:alter table tb_name
modify,change,add,drop
insert into tb_name(col1,col2,...) values|value ('string',num,...);
update tb_name set column=value where condition;
delete from tb_name where condition;
select 字段 from tb_name where condition
*:所有字段
where:没有条件表示显示所有行
创建用户:
create user 'username'@'host' identified by 'password';
drop user 'username'@'host';
grant pri1,pri2,...on db_name.tb_name to 'username'@'host' [identified by 'password'];
revoke pri1,pri2,... on db_name.tb_name from 'username'@'host';
查看用户的授权:show grants for 'username'@'host';
flush privileges;
为用户设定密码:
mysql>set password for 'username'@'host'=password('password');
# mysqladmin -uusername -hhost -p password 'password'
mysql>update user set password=password('password') where user='root' and host='127.0.0.1';

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