MSSQL 删除重复并只保留一条

重复值查找

select field1,field2 from table
group by field1,field2  having COUNT(*)>1

删除重复值，只保留ID最小的那条

delete table
where field1 in (select field1 from VersionProductRelation a
group by field1,field2 having COUNT(*)>1)

and field2 in (select field2 from VersionProductRelation a
group by field1,field2 having COUNT(*)>1)

and ID not in (
select MIN(ID) from table 
group by field1,field2 having COUNT(*)>1)

原文：https://www.cnblogs.com/Alex-Mercer/p/12263095.html