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mysql基本常识整理

mysql> show databases; mysql> show databases \G #以行的方式显示 mysql> show table status from test where name='student' \G

mysql> create database HA;

mysql&gt; drop database <code>HA-test</code>

mysql&gt; show tables;

mysql&gt; create table student(id int(20),name char(40),age int);语法:create table 表名 (字段名 类型, 字段名 类型, 字段名 类型);

mysql&gt; desc student;

mysql&gt; show create table student \G

mysql&gt; create table student2(id int(20),name char(40),age int)ENGINE=MyISAM DEFAULT CHARSET=utf8;

mysql&gt; drop table student2;

mysql&gt;alter table student rename students;

mysql&gt; alter table students change name stname char(20);

mysql&gt; alter table students add sex enum('M','W');语法:alter table 表名 add 字段名 字段类型;

mysql&gt; alter table students add uid int(10) first;在第一列添加一个字段; mysql&gt; alter table students add address char(40) after age;在age后面添加一个address字段:

mysql&gt; alter table students drop address;语法:alter table 表名 drop 字段名 ;

mysql&gt; select * from students;*表示所有

mysql&gt; select name from student;

mysql&gt; select *from HA.student; 数据库名.表名 语法:SELECT 字段 FROM 数据库名.表名;

mysql&gt; insert into students values(1,'zhangs',21);语法:insert into 表名values (字段值1,字段值2, 字段值3);

mysql&gt; insert into student values(2,'lis',24),(3,'wange',26);

mysql&gt; delete from students where id=3;删除id为3的行

mysql&gt; update students set sex='M' where id=2; 从id 为2 的 sex 改成M mysql&gt; update students set age=10 where id=2 ; 从id为2 的 age 改成10 mysql&gt; update students set id=2; 所有的都变为2

mysql&gt; update students set stname='zhangsan',age=21 where uid=1; 从uid 为1 的

mysql&gt; select name,age from students;

mysql&gt; select id,name,age from students where id&gt;3 and age&gt;25;

mysql&gt; select * from students where name='lis' and (age=21 or age=10);

mysql&gt; select * from student where name like 'li%';

mysql&gt;select * from student where name like '%is%' and name like '%a%'; +------+------------+------+ | id | name | age | +------+------------+------+ | 7 | siswaisaaa | 20 | +------+------------+------+ 1 row in set (0.00 sec)

mysql&gt; select name from students where binary name='ZHANGS';

mysql&gt; select distinct id from students order by id;

mysql&gt; select distinct id,name from students order by id desc;### 查询id 降序查询

方法1; mysql&gt; set password for root@localhost = password('123456');

方法2:用mysqladmin 格式:mysqladmin -u用户名 -p旧密码 password 新密码 例子:mysqladmin -uroot -p123456 password 123

方法3:用UPDATE直接编辑user表 首先登录MySQL。 mysql&gt; use mysql; mysql&gt; update user set password=password('123') where user='root' and host='localhost'; mysql&gt; flush privileges;刷新

[root@xuegod210 ~]# mysqldump -uroot -p123456 HA &gt; HA.dump 备份完整数据

[root@xuegod210 ~]# mysqldump -uroot -p123456 --no-data --databases HA &gt; ha.dump 备份表结构(没有完整数据)

mysql&gt; source /root/books.sql; ##导入表时,不需要重新,创建表。 先use 库

mysql&gt; show engines;

mysql&gt; show variables like '%storage_engine%'; alter table student engine=innodb;

mysql&gt; alter table student engine=innodb; 修改表的引擎

整体上来说,复制有3 个步骤:

(1) master 将改发记录到二迚制日志(binary log)中(这些记录叨做二迚制日志事件,binarylog events);

(2) slave 将master 的binary log events 拷贝到它的中继日志(relay log);

(3) slave 重做中继日志中的事件,修改salve 上的数据;

本文转自 Innocence_caosm 51CTO博客,原文链接:http://blog.51cto.com/innocence/1954772,如需转载请自行联系原作者