本文介绍了如何从 MySQL 表中删除重复的行的处理方法，对大家解决问题具有一定的参考价值，需要的朋友们下面随着小编来一起学习吧！
问题描述
我有一个 MySQL 表，例如:
I have a MySQL table like:
ID, Col1, Col2, Col3, Col4, etc...
ID 是一个主键，自表创建以来一直有效.
ID is a primary key and has been working since the table's creation.
我想要做的是删除所有其他列都相同的记录.
What I want to do is delete all but one records where all the other columns are identical.
推荐答案
DELETE DupRows.*
FROM MyTable AS DupRows
INNER JOIN (
SELECT MIN(ID) AS minId, col1, col2
FROM MyTable
GROUP BY col1, col2
HAVING COUNT(*) > 1
) AS SaveRows ON SaveRows.col1 = DupRows.col1 AND SaveRows.col2 = DupRows.col2
AND SaveRows.minId <> DupRows.ID;
当然，您必须将所有三个位置的 col1、col2 扩展到所有列.
Of course you have to extend col1, col2 in all three places to all columns.
我刚刚从我保留并重新测试的脚本中提取了它，它在 MySQL 中执行.
I just pulled this out of a script I keep and re-tested, it executes in MySQL.
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