问题描述:提供一个csv文件,记录的是一些不同数据库的不同表中的共同字段account_id数据,需要在A库的account表中做关联删除
解决思路:csv文件中储存的都是account_id,六位纯数字id。可以建立一张临时表,将csv数据导入临时表中,最后做关联删除。
1.备份原表 CREATE table A.account_0220 as select * from A.account; alter table A.account_0220 comment = 'This is a backup table. Please drop it after 20230320'; 2.导入数据到临时表 创建临时表 create table test.transit_tmp(account_id int); 导入数据到临时表 load data local infile '/tmp/0220/202302201526.csv' into table test.transit_tmp fields terminated by ',' optionally enclosed by '"' escaped by '"' lines terminated by '\r\n'; 查询临时表数据量 select count(*) from transit_tmp; +----------+ | count(*) | +----------+ | 10369 | +----------+ 1 row in set (0.003 sec) 3.查询数据是否匹配 查询account表中与tmp关联数据行数,查询到匹配数据与实际csv数据相差一行 MariaDB [(none)]> select count(*) from A.account where account_id in (select * from test.transit_tmp); +----------+ | count(*) | +----------+ | 10368 | +----------+ 1 row in set (42.539 sec)
MariaDB [test]> select * from transit_tmp order by account_id asc limit 1;
+------------+
| account_id |
+------------+
| 0 |
+------------+
1 row in set (0.003 sec)
MariaDB [test]> select * from transit_tmp order by account_id asc limit 2;
+------------+
| account_id |
+------------+
| 0 |
| 261607 |
+------------+
2 rows in set (0.003 sec)
查询到数据不匹配,csv文件中有一行是字段名,load data把account_id这一行当成0插入到了临时表中
删除test.transit_tmp表中数据为0的一行
delete from test.transit_tmp where account_id='0';
4.清理目标表相关数据
set autocommit=0;
delete from A.account where account_id in (select * from test.transit_tmp);
commit;