大数据学习27：Hive元数据清理，从mysql层面删除hive元数据

由于之前配置了hive，hdfs 被格式化了，导致现在hive上原来的元数据没有清理掉。

由于hive 上所有元数据均保存在mysql中，所以，可以从mysql上删除表相关信息即可删除hive表，而且不会影响hdfs上数据。

分析：

hive在mysql上的相关元数据表关系图：



Hive在mysql的元数据表的关系和含义这篇博文中有详细字段说明：

http://blog.csdn.net/ggwxk1990/article/details/78162442

解决方法：

1、先在 mysql 中建存储过程

说明：

建的存储过程名字为t1，输入为tbl_id。因为表名可能重复，但是tbl_id不会。

DELIMITER //
drop procedure if exists t1;
create  procedure t1 ( in tbinput int)
begin
declare v_sd_id int ;
declare v_part_id int ;
declare v_cd_id int ;
declare v_serde_id int ;

select tbinput;
select SD_ID into v_sd_id from tbls where TBL_ID = tbinput;
select part_id  into v_part_id from partitions where tbl_id = tbinput;
select cd_id , serde_id into v_cd_id,v_serde_id from sds where sd_id = v_sd_id;
select v_sd_id,v_part_id,v_cd_id,v_serde_id;

if v_part_id is not  null then
delete from partition_params where part_id = v_part_id;
delete from partition_key_vals where part_id = v_part_id;

end if;
delete from serdes where serde_id = v_serde_id;
delete from serde_params where serde_id = v_serde_id;
delete from columns_v2 where cd_id = v_cd_id;
delete from sds where sd_id = v_sd_id;
delete from partitions where tbl_id = tbinput;
delete from partition_keys where tbl_id = tbinput;
delete from table_params where tbl_id = tbinput;
delete from tbls where tbl_id = tbinput;

end ;
//
delimiter ;

2、编写shell(最好用mysql的用户去执行shell)：

hadoop002:mysqladmin:/usr/local/mysql:>cat mysql_delete.sh
#!/bin/bash
source /usr/local/mysql/.bash_profile
mysql -uroot -ppassword hive3 -e "
SET FOREIGN_KEY_CHECKS = 0;
call t1(71);
SET FOREIGN_KEY_CHECKS = 1;
quit" >> /tmp/mysql_delete.log

完成！