刪除重複行，並保持

Question

一行

這是我的表的名稱Result_Simul

這是值

 Pk FkIdResult FkIdSimul 
     1  43   1244 
     2  43   1244 
     3  52   1244 
     4  52   1244 

如何保持自顧自地行PK = 1和PK = 3，刪除PK = 2和Pk = 4

感謝您的幫助。

我不是在TSQL真的好

弗蘭克

Answer 1

您可以使用row_number給每個重複的上升數字，然後刪除第二和更高的重複：

delete tbl 
from (
     select row_number() over (partition by FkIdResult, FkIdSimul 
            order by Pk desc) as rn 
     ,  * 
     from YourTable 
     ) tbl 
where rn > 1 

Working example at SE Data.

Answer 2

in mysql：

create temporary table table2 as (select min(pk) as pk from Table1 group by FkIdResult );  
delete from Table1 where pk not in (select pk from table2)