如果超过 100k 条记录，则从 table 中删除记录

Question

我有一个条件，在审计日志中，如果记录超过100k，则删除以前的旧记录，我不想删除所有100k记录，但只想删除旧记录，我想维护最新的 10 万条记录。

下面是我试过的查询，请任何人帮助我，如何准备查询。

DELETE FROM  audit_logs where 
id not in (SELECT id from audit_logs order by ID DESC LIMIT 100000);

Answer 1

您可以包装到另一个 select 子查询中；

DELETE FROM  audit_logs 
WHERE  id not in  (SELECT t1.id 
                   FROM ( SELECT id 
                          FROM audit_logs 
                          ORDER BY ID DESC 
                          LIMIT 100000
                         ) as t1
                    );

或使用NOT EXISTS：

    DELETE FROM  audit_logs  a1 
    WHERE  NOT EXISTS   ( SELECT * 
                          FROM ( SELECT id 
                                 FROM audit_logs a2
                                 ORDER BY ID DESC 
                                 LIMIT 100000
                               ) as t1
                         );

阅读更多内容：https://dev.mysql.com/doc/refman/8.0/en/update.html

如果超过 100k 条记录，则从 table 中删除记录

Delete records from table, if it exceeds 100k records

mysql

mysql-8.0