课程大纲：
1. 忘记root密码
编辑mysql主配置文件 my.cnf 在[mysqld]字段下添加参数 skip-grant ,重启数据库服务,这样就可以进入数据库不用授权了 mysql -uroot ,修改相应用户密码 use mysql; update user set password=password(‘your password‘) where user=‘root‘;flush privileges; 最后修改/etc/my.cnf 去掉 skip-grant , 重启mysql服务
2. skip-innodb 我们可以增加这个参数不使用innodb引擎。
3. 配置慢查询日志
#log_slow_queries = /path/to/slow_queries
#long_query_time = 1
4. mysql常用操作
mysql 远程备份和恢复
远程登录mysql
116.211.105.59 先授权
mysql -uroot -paming
mysql> grant all on *.* to ‘root‘@‘58.53.94.11‘ identified by ‘123aaa‘;
mysql> select user();
+----------------+
| user() |
+----------------+
| [email protected] |
+----------------+
1 row in set (0.00 sec)
mysql> select database();
mysql> select database();
+------------+
| database() |
+------------+
| NULL |
+------------+
1 row in set (0.00 sec)
mysql> grant all on discuz.* to ‘user1‘@‘192.168.10.*‘ identified by ‘123aaa‘;
discuz
user1
123aaa
mysql> flush privileges;
mysql> show processlist;
58.53.94.11 登录
[[email protected] ~]# mysql -uroot -h116.211.105.59 -P3306 -p123aaa
[[email protected] /]# mysqldump --host 111.47.123.72 -uroot -paminglinux discuz > /data/discuz.sql
mysqldump: Got error: 1130: Host ‘111.47.123.67‘ is not allowed to connect to this MySQL server when trying to connect
[[email protected] /]# mysqldump --host 111.47.123.72 -uroot -paminglinux discuz > /data/discuz.sql
[[email protected]uhan-67 /]# cd /data
[[email protected] data]# ll
total 2308
-rw-r--r-- 1 root root 2361322 Aug 3 22:27 discuz.sql
查看都有哪些库 show databases;
查看某个库的表 use db; show tables;
查看表的字段 desc tb;
查看建表语句 show create table tb;
当前是哪个用户 select user();
当前库 select database();
创建库 create database db1;
创建表 create table t1 (`id` int(4), `name` char(40));
查看数据库版本 select version();
查看mysql状态 show status;
修改mysql参数 show variables like ‘max_connect%‘; set global max_connect_errors = 1000;
查看mysql队列 show processlist;
创建普通用户并授权 grant all on *.* to user1 identified by ‘123456‘;
grant all on db1.* to ‘user2‘@‘10.0.2.100‘ identified by ‘111222‘;
grant all on db1.* to ‘user3‘@‘%‘ identified by ‘231222‘;insert into tb1 (id,name) values(1,‘aming‘);
更改密码 UPDATE mysql.user SET password=PASSWORD("newpwd") WHERE user=‘username‘ ;
查询 select count(*) from mysql.user; select * from mysql.db; select * from mysql.db where host like ‘10.0.%‘;
插入 update db1.t1 set name=‘aaa‘ where id=1;
清空表 truncate table db1.t1;
删除表 drop table db1.t1;
删除数据库 drop database db1;
修复表 repair table tb1 [use frm];
5. mysql备份与恢复
[[email protected] ~]# find / -name mysqldump
/usr/local/mysql/bin/mysqldump
[[email protected] mysql]# mysqldump -uroot -paming discuz > /data/discuz.sql/1.sql
linux mysql 清除密码
1、以root登录：mysql -u root -p
2、mysql>use mysql;
3、mysql>update user set password=‘‘ where user=‘root‘;
备份 mysqldump -uroot -p db >1.sql
恢复 mysql -uroot -p db <1.sql
只备份一个表 mysqldump -uroot -p db tb1 > 2.sql
备份时指定字符集 mysqldump -uroot -p --default-character-set=utf8 db >1.sql
恢复也指定字符集 mysql -uroot -p --default-character-set=utf8 db < 1.sql
扩展知识：
myisam 和innodb引擎对比 http://www.pureweber.com/article/myisam-vs-innodb/
一台mysql服务器启动多个端口 http://www.lishiming.net/thread-63-1-1.html
SQL语句教程 http://blog.51cto.com/zt/206
sql教程pdf文档 http://class.ccshu.net/00864091/ ... %95%99%E7%A8%8B.pdf
什么是事务？事务的特性有哪些？ http://blog.csdn.net/yenange/article/details/7556094
mysql常用引擎 http://c.biancheng.net/cpp/html/1465.html
批量更改表的引擎 http://www.361way.com/change-mysql-engine/1729.html
mysql 二进制日志binlog的模式 http://lihuipeng.blog.51cto.com/3064864/833017
mysql根据binlog恢复指定时间段的数据 http://www.centoscn.com/mysql/2015/0204/4630.html
mysql字符集调整 http://xjsunjie.blog.51cto.com/999372/1355013
使用xtrabackup备份innodb引擎的数据库 http://www.aminglinux.com/bbs/thread-956-1-1.html
innobackupex 备份 Xtrabackup 增量备份 http://www.aminglinux.com/bbs/thread-1012-1-1.html