e.g。我想删除下表中的最新三条记录
root@localhost:[test]10:14:02>select * from delete_test order by create_time desc;
+----+------+---------------------+
| id | code | create_time |
+----+------+---------------------+
| 9 | fff | 2016-06-18 10:08:28 |
| 8 | eee | 2016-06-18 10:08:21 |
| 7 | ddd | 2016-06-18 10:08:15 |
| 3 | ccc | 2016-06-17 22:18:48 |
| 2 | bbb | 2016-06-17 22:18:42 |
| 1 | aaa | 2016-06-17 22:18:37 |
+----+------+---------------------+
首先我尝试了
root@localhost:[test]10:14:14>delete from delete_test where code in (select code from delete_test order by create_time desc limit 3);
ERROR 1235 (42000): This version of MySQL doesn't yet support 'LIMIT & IN/ALL/ANY/SOME subquery'
然后我试了
root@localhost:[test]10:17:05>delete a from delete_test a, (select code from delete_test order by create_time desc limit 3) b where a.code = b.code;
ERROR 1175 (HY000): You are using safe update mode and you tried to update a table without a WHERE that uses a KEY column
但提交的code
为unique key
。
然后我试了
root@localhost:[test]10:18:49>delete a from delete_test a join (select code from delete_test order by create_time desc limit 3) b on a.code = b.code where a.id>0;
ERROR 1175 (HY000): You are using safe update mode and you tried to update a table without a WHERE that uses a KEY column
但我明确地使用了primary key
。
所以我想知道如何在--safe-updates
模式中删除最新的一些记录?
答案 0 :(得分:0)
你可以这么简单:
delete from delete_test order by create_time limit 3;
在此处查看:http://sqlfiddle.com/#!9/04f68/1
如果我没有按顺序排列,只需将order by
部分更改为order by create_time desc