sql去除重复记录 且保留id最小的

第一步：查询重复记录

SELECT * FROM TableName
WHERE RepeatFiled IN (
SELECT RepeatFiled
FROM TableName
GROUP BY RepeatFiled
HAVING COUNT(RepeatFiled) > 1
)

这一段逻辑很简单，就是把重复条数大于1的全部都搞出来就行了。

第二步：删除重复记录，只保留一条

SELECT * FROM TableName
WHERE RepeatFiled IN (
SELECT RepeatFiled
FROM TableName
GROUP BY RepeatFiled
HAVING COUNT(RepeatFiled) > 1
AND
ID NOT IN (
SELECT MIN(ID)
FROM TableName
GROUP RepeatFiled
HAVING COUNT(RepeatFiled) > 1
)
)

在上一步的基础上继续过滤，那就把最小值留下就行了，大功告成！