Mysql查看表的元数据信息

1.查看表的创建时间和更新时间

SELECT *  FROM `information_schema`.`TABLES` WHERE `information_schema`.`TABLES`.`TABLE_SCHEMA` = 'XXX' AND `information_schema`.`TABLES`.`TABLE_NAME` = 'XXX'\G
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2.查看正在运行的进程

SELECT * FROM information_schema.PROCESSLIST p where (p.INFO is not NULL or p.COMMAND='Query') AND USER='hadoop';

show processlist;
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3.统计MySQL中指定数据库中有多少张表

SELECT count(*) TABLES, table_schema FROM information_schema.TABLES
where table_schema = '数据库名称xxx' GROUP BY table_schema;
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4.统计MySQL中指定数据库中表记录数

use information_schema;
select table_name,table_rows from tables where TABLE_SCHEMA = '数据库名称xxx' order by table_rows desc;

where table_schema = '你的数据库名'
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