网站代码需要注意什么问题吗,太原网站推广,网络推广平台中心,网页设计尺寸详解今天介绍的是关于Mysql数据库一些操作的基础命令用户与权限创建用户mysqlcreate user test identified by BaC321#; 修改密码5.5版本及以前的命令mysqlset password for testpassowrd(!1A2#3); 5.6及以上命令mysqlupdate mysql.user set authentication_stringpass…今天介绍的是关于Mysql数据库一些操作的基础命令用户与权限创建用户mysqlcreate user test identified by BaC321#; 修改密码5.5版本及以前的命令mysqlset password for testpassowrd(!1A2#3); 5.6及以上命令mysqlupdate mysql.user set authentication_stringpassword(A1b2c3#!) where usertest; 创建用户并授权mysqlgrant select,insert,update on student.* to testlocalhost identified by A1b2c3#!; 查看授权mysql show grants for testlocalhost; 移除权限mysql revoke insert,update on student.* from testlocalhost; 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 age25 where namezhang;
mysql update T1 set age23 where nameli; 删除数据mysql delete from T1 where age22; 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 doesnt exist
#提示此视图不存在 以上有不足的地方可以指出讨论觉得不错的朋友希望能得到您的转发支持同时可以持续关注我每天分享Linux C/C后台开发干货内容
