//列出 MySQL Server 数据库。
SHOW DATABASES

//列出数据库数据表。
SHOW TABLES [FROM db_name]

//列出数据表及表状态信息。
SHOW TABLE STATUS [FROM db_name]

//列出表字段
SHOW COLUMNS FROM tbl_name [FROM db_name]

//列出表字段及注释
SHOW FIELDS FROM tbl_name [FROM db_name],DESCRIBE tbl_name [col_name]

//列出字段及详情
SHOW FULL COLUMNS FROM tbl_name [FROM db_name]

//列出字段完整属性
SHOW FULL FIELDS FROM tbl_name [FROM db_name]

//列出表索引
SHOW INDEX FROM tbl_name [FROM db_name]

//列出 DB Server 状态。  
SHOW STATUS      
   
//列出 MySQL 系统环境变量。                         
SHOW VARIABLES

//列出执行命令。
SHOW PROCESSLIST

//列出某用户权限
SHOW GRANTS FOR user