Question

我有一个Union Query用于从表中获取结果。当只有第一个查询执行那个时候这个工作正常但如果在第二个（联合部分）也返回结果那个时间它将不起作用。我的查询如

Select * from (
Select  ROW_NUMBER() OVER(ORDER BY EmpID DESC) as RowNo,
    Emp.EMPID, EMP.FirstName
    From Emp
Union
Select ROW_NUMBER() OVER(ORDER BY EMPID DESC) as RowNo,
    Emp.EMPID, EMP.FirstName
    From Emp Inner Join EMPDetail On Emp.EmpID = EMPDetail.EMPID 
    Where EMPDetail.IsActive=True
    ) as _EmpTable where RowNo between 1 and 20

请帮帮我。我想使用行号添加分页。还有其他解决办法吗？

Answer 1

在执行union之前，您需要在row_number()ing周围使用其他子查询：

Select * 
from 
(
    Select  ROW_NUMBER() OVER(ORDER BY EmpID DESC) as RowNo,
        EmpID, 
        FirstName
    FROM
    (
        SELECT 
            Emp.EMPID, 
            Emp.FirstName
        From Emp

        Union

        Select 
            Emp.EMPID, 
            EMP.FirstName
        From 
            Emp Inner Join EMPDetail On Emp.EmpID = EMPDetail.EMPID 
        Where 
            EMPDetail.IsActive=True
    )
) as _EmpTable 
where 
    RowNo between 1 and 20

Answer 2

这可能对你有所帮助 -

SELECT * 
FROM (
    SELECT *, ROW_NUMBER() OVER (ORDER BY e.EmpID DESC) AS RowNo
    FROM (
        SELECT /*TOP 20*/
            e.EmpID,
            e.FirstName
        FROM dbo.Emp e
        ORDER BY e.EmpID DESC

        UNION

        SELECT /*TOP 20*/
            e.EMPID,
            e.FirstName
        FROM dbo.Emp e
        WHERE EXISTS(
            SELECT 1 
            FROM dbo.EMPDetail ed
            WHERE e.EmpID = ed.EmpID
                AND ed.IsActive = 'TRUE'
        ) 
        ORDER BY e.EmpID DESC
    ) t
) t
WHERE t.RowNo BETWEEN 1 AND 20

如何在ROW_NUMBER（）函数和Union中获取过滤器记录？

2 个答案: