mysql 学习笔记篇_MySQL
作为一个运维人员,不光是要学会mysql服务的搭建和安装,也要懂得基础命令及语法的使用。 这是我学习之后总结出来的笔记,希望对和我一样的菜鸟有所帮助。 一、登录mysql数据库 1、连接本地mysql数据库,默认端口为3306。 #mysql –u root –p 123456 //-u:指定用户 -p:指定与用户对应的密码。 2、通过IP和端口连接远程mysql服务器。 #mysql –u root –p 123456 –h 192.168.100.1 –P 3306 //-h:指定数据库服务器IP -P:指定要连接的端口号。 3、通过TCP连接管理不同端口的多个MySQL(注意:MySQL4.1以上版本才有此项功能) #mysql -u root –p 123456 --protocol=tcp --host=localhost --port=3307 4、通过socket套接字管理不同端口的多个MySQL #mysql -u root -p --socket=/tmp/mysql3307.sock 5、退出mysql. >exit; 二、数据库操作语句 1、显示所有数据库。 >show databases; 2、创建一个test1234数据库。 >create database test1234; 3、选定test1234数据库。 >use test1234; 4、删除test1234数据库。 >drop database test1234; 三、表操作语句 1、显示当前库中的所有表。 >show tables; 2、在当前库中创建一个user表,字段id为主键、唯一索引,存储引擎为MYISAM。 >create table user (id int(5) unsigned,name char(10) not null, pass char(20) not null,primary key (id)) engine = myisam; 3、查看user表结构。 >describe user; 4、 查询user表中的记录。 >select * from user; 5、在user表中指定条件查询。 >select * from user where name = 'zhangsan' ; 6、查询user表,并按id排序。 >select * from user order by id desc; 7、在user表中指定字段name、pass查询。 >select name,pass from user; 8、在user表中查询唯一不重复的记录。 >select distinct name from user; 9、向user表中插入记录。 >insert into user (id,name,pass) values (1,'zhangsan','123456'); 10、更新user表中的指定信息。 >update user set pass='123456' where name='zhangsan'; 11、给user表的pass字段后增加date字段。 >alter table user add column date char(8) after pass; 12、在user表中修改pass字段名及字段数据类型。 >alter table user change column pass password char(10); 13、在user表中删除date字段。 >alter table user drop column date; 14、删除user表中指定的信息。 >delete from user where id=1; 15、删除user表中所有的信息。 >delete from user; 16、删除user表。 >drop table user; 四、数据库权限操作 1、创建一个具有root权限,可从任意IP登录的账号test123。 >grant all privileges on *.* to ' test123'@'%' identified by '123456'; 2、创建一个针对mysqltest库具有数据操作权限的账号test1234,并且只能从192.168.1.10登录。 >grant select,insert,update,delete on mysqltest to 'test1234'@'192.168.1.10' identified by '123456'; 3、收回test1234账号针对mysqltest库的某些数据操作权限。 >revoke insert,update,delete on mysqltest from 'test1234'@'192.168.1.10' identified by '123456'; 4、删除test1234用户。 >drop user 'test1234'@'%'; 五、mysqld的备份还原 1、备份mysqltest数据库。 #mysqldump –u root –p 123456 mysqltest > bak_mysqltest.sql 2、备份mysqltest数据库下user表的数据。 #mysqldump –u root –p 123456 mysqltest user > bak_table_mysqltest_user.sql 3、备份mysqltest数据库,并压缩。 #mysqldump –u root –p 123456 mysqltest | gzip > bak_mysqltest.sql.gz 4、恢复mysqltest.sql到mysqltest库中。 #mysql –u root –p 123456 mysqltest 六、mysql其它命令 1、启动mysql服务。 #service mysqld start 源码包安装不适用 #/etc/init.d/mysqld start 源码包安装不适用 #/usr/local/mysql/bin/mysqld_safe –user=mysql & 2、关闭mysql服务。 #service mysqld stop 源码包安装不适用 #/etc/init.d/mysqld stop 源码包安装不适用 #/usr/local/mysql/bin/mysqladmin –p 123456 shutdown 这里的-p指的是mysql管理员账号的密码。 3、重启mysql服务。 #service mysqld restart 源码包安装不适用 #/etc/init.d/mysqld restart 源码包安装不适用 4、将源码包安装的mysql加入到开机自启动。 #echo "/usr/local/mysql/bin/mysqld_safe --user=mysql &" >>/etc/rc.local 5、将源码包安装的mysql加入环境变量中。 #echo "export PATH=$PATH:/usr/local/mysql/bin" >>/etc/profile 加入环境变量 #source /etc/profile 更新环境变量

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