使用单独的列检查 SQL 删除重复项

Question

我有 2 个表，其中包含相同的列和权限记录。两个表中都有一个名为 IsAllow 的列。我正在使用 UNION 合并获取两个表的记录但是如果任何一列中的 IsAllow = 0，我想跳过类似的记录 - 我不想要这些记录。但是 UNION returns 所有记录都变得混乱了。

 Below are columns 
 IsAllow, UserId, FunctionActionId

I tried union but it gives both records. I want to exclude IsAllow = 0 in either table.

Sample data table 1
IsAllow UserId FunctionActionId
1         2           5
1         2           8

Sample data table 2
IsAllow UserId FunctionActionId
0         2           5 (should be excluded)
1         2           15

Answer 1

你可以试试这个：

;with cte as(select *, row_number() 
                       over(partition by UserId, FunctionActionId order by IsAllow desc) rn 
            from 
             (select * from table1
              union all
              select * from table2) t)
select * from cte where rn = 1 and IsAllow = 1

版本 2：

select distinct coalesce(t1.UserId, t2.UserId) as UserId, 
                coalesce(t1.FunctionActionId, t2.FunctionActionId) as FunctionActionId,
                1 as IsAllow
from tabl1 t1
full join table2 t2 on t1.UserId = t2.UserId and 
                       t1.FunctionActionId  = t2.FunctionActionId 
where (t1.IsAllow = 1 and t2.IsAllow = 1) or
      (t1.IsAllow = 1 and t2.IsAllow is null) or
      (t1.IsAllow is null and t2.IsAllow = 1)

使用单独的列检查 SQL 删除重复项

Remove duplicate with separate column check TSQL

tsql

sql-server-2008-r2