SQL Server with multiple identical data deletions

1: Add a Difference field, judge the Difference field to delete

Delete from (select Row_number () over (partition by code order by time DESC) as rows A, code, time from table) where a > 2

2: Query out more than 1 of the table data, query out the difference, according to the difference to delete

Select Difference field from Table a right join (select Code, MIN (time) Minimum time from table group by SDDM have COUNT (code) >1) b on a. Code = B. Code an D A. Time = B. Time Order by a. Code

SQL Server with multiple identical data deletions