• mysql基础命令


    创建用户

    mysql>create user test identified by 'BaC321@#';

    修改密码

    ##5.5版本及以前的命令

    mysql>set password for test=passowrd('!1A@2#3');  

    ##5.6及以上命令

    mysql>update mysql.user set authentication_string=password('A1b2c3#!@') where user='test';

    创建用户并授权

    mysql>grant select,insert,update on student.* to test@localhost identified by 'A1b2c3#!@';

    查看授权

    mysql> show grants for test@localhost;

                           

    移除权限

    mysql> revoke insert,update on student.* from test@localhost;

    建库与表

    创建库

    mysql> create database student;

    mysql> show databases;

     

    创建表

    mysql> use student;

    mysql> create table T1 (name varchar(10) not null,sex varchar(10) not null);

    ##通过现有的表创建新表

    mysql> create table T2 as select * from T1;

    插入数据

    插入数据

    mysql> insert into T1 values('zhang','man');

    Query OK, 1 row affected (0.03 sec)

    mysql> insert into T1 values('li','man');

    Query OK, 1 row affected (0.03 sec)

    mysql> insert into T1 values('wang','man');

    Query OK, 1 row affected (0.02 sec)

    mysql> insert into T1 values('zhao','women');

    Query OK, 1 row affected (0.05 sec)

    ##需要注意的是如果列超过两列,就需要指定列字段名如下

    mysql> insert into T1(name,sex) values('gege','man');

    查询数据

    查询数据

    mysql> select user,host from mysql.user;

    ### 查看用户

    mysql> select * from T1 where name like '%an%';

    mysql> select * from T1 where age like '2%';

    ##匹配查询

     

    mysql> select * from T1 order by name,age;

    ##查询排序

     

    mysql> select count(*) as toaolcount from T1;

    mysql> select sum(age) as sumvalue from T1;

    mysql> select avg(age) as avgvalue from T1;

    mysql> select max(age) from T1;

    ##查询值

     

    mysql> select score from T1 where score <91;

    mysql> select score from T1 where score >=91;

    mysql> select * from T1 where score in (96,100);

    ##条件查询

     

    mysql> select * from T2;

    mysql> select * from T1;

     


    增删更新

    增加与删除列

    mysql> alter table T1 add age int(4) not null;

    mysql> alter table T1 drop age

    更新表里的数据

    mysql> update T1 set age=25 where name='zhang';

    mysql> update T1 set age=23 where name='li';

    删除数据

    mysql> delete from T1 where age='22';

    建索引与删除

    mysql> create index indexT1 on T1(name(10));

    mysql> drop index indexT1 on T1;

    主键与视图

    创建主键

    mysql> alter table T1 add primary key(name);

    mysql> desc T1;

     

    创建与删除视图

    mysql> create view t1view as select name from T1;

    mysql> select * from t1view;

     

    mysql> drop view t1view;

    mysql> select * from t1view;

    ERROR 1146 (42S02): Table 'student.t1view' doesn't exist

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  • 原文地址:https://www.cnblogs.com/guarderming/p/9418641.html
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