我有一张表格,其中包含以下列:
ID(primary key),
USER,
ACTION
TIME
LOCATION
我正在尝试使用列USER,ACTION,TIME,LOCATION
一起删除重复条目。
我编写了以下查询:
DELETE FROM test.testlogins
WHERE id IN (SELECT *
FROM (SELECT id FROM test.testlogins
GROUP BY USER, ACTION, TIME, LOCATION HAVING (COUNT(*) > 1)
) AS A
);
然而,当我执行它时,每次只删除一行。我的测试数据有大约40多行是重复的,每个都分配了一个单独的id
。
CREATE UNIQUE INDEX idx_userlogins ON testlogins (USER, ACTION, TIME, LOCATION)
创建一个唯一索引。 - fthiella