概述

在centos系统下的默认安装目录结构

主从复制

常用语句

# 查询一个数据库有多少张数据表；
select count(*) TABLES,table_schema from information_schema.TABLES where table_schema = 'ultrax' group by table_schema;

# 查看某张表的字段信息；
mysql> desc pre_common_connect_guest;

# 查看mysql默认引擎
show variables like '%storage_engine%';

# 列出某数据库表名中包含某字段的表
select table_name from information_schema.tables where table_schema='wpc' and table_type='base table' and table_name like '%_data';

锁表问题

# mysql查看表的状态
show OPEN TABLES where In_use > 0;

# 查看锁表进程
mysql> show processlist;
mysql> kill  112498;  #进程ID

重置密码

# 无密码启动
/usr/local/mysql/bin/mysqld_safe --skip-grant-tables >/dev/null 2>&1 &

update user set password = Password('123456') where User = 'root';
flush privileges;