MYSQL基本命令操作
1.登录方法: mysql -u root -p
2.显示所有数据库: show databases;
3.操作指定数据库(以information_schema为例) use information_schema
4.显示所有的表 show tables;
5.显示表结构(以users表为例) discribe tables;
6.查询所有数据库的大小: select concat(round(sum(data_length/1024/1024),2),'MB') as data from tables;
7.查询指定数据库的大小(以zabbix为例): select concat(round(sum(data_length/1024/1024),2),'MB') as data from tables where table_schema='zabbix';
8.查询指定数据库中所有表的大小(以zabbix为例): SELECT TABLE_NAME,DATA_LENGTH+INDEX_LENGTH,TABLE_ROWS,concat(round((DATA_LENGTH+INDEX_LENGTH)/1024/1024,2), 'MB') as data
FROM information_schema.tables WHERE TABLE_SCHEMA='zabbix' ORDER BY DATA_LENGTH+INDEX_LENGTH desc;
9.查询指定数据库中指定表的大小(以zabbix数据库的history表为例): select concat(round(sum(data_length/1024/1024),2),'MB') as data from tables where table_schema='zabbix' and table_name='history';``