Question

我有一个CTE查询，但我没有任何关于它的概念。我是编程新手。实际上我的查询中有数量列，我想重复行直到数量。表示如果qty等于50，则数据集返回50个时间记录。如果qty等于1000万则查询返回10000万条记录。以下查询对我来说很好，直到＆lt; 99 rcords我怎么能为1000个rocords增长。

提前完成。

SELECT * INTO #TableA
FROM
(

SELECT MIS_Request_Detail.vno, MIS_Request_Detail.IID
       , MIS_Request_Detail.Qty-MIS_Request_Detail.BalQty qty, 
       1 RcvdQty, pk,
       ItmMstr.IName, ItmMstr.UName, '' SrNo,
       MIS_Request_Detail.Qty As ReqQty, MIS_Request_Detail.BalQty
       , MIS_Request_Detail.Qty-MIS_Request_Detail.BalQty RemainQty
FROM MIS_Request_Detail INNER JOIN
view_MIS_Item_Master ItmMstr ON ItmMstr.IID=MIS_Request_Detail.IID
WHERE ReqType=1 AND MIS_Request_Detail.vno=@vno 

) T
;WITH Nbrs ( Number ) AS (
SELECT 1 UNION ALL
SELECT 1 + Number FROM Nbrs WHERE Number < 99 
)

SELECT A.vno,A.IID, A.IName, A.UName, CAST(SrNo AS VARCHAR(50)) SrNo
   , CAST(N.Number AS varchar(50)) QTY, pk ReqDetpk, RcvdQty,
   A.ReqQty, A.BalQty, A.RemainQty, 0 Color,  0 chked, 0 Pk, 0 AS isupdate
   , '' AS isdeleted
FROM #TableA A
JOIN Nbrs N ON N.Number <= A.qty
ORDER BY IID, N.Number, pk

Answer 1

正如您可能发现的那样，递归CTE的递归限制为99。要解决这个问题，你必须使用SQL Magazine article by Itzik Ben-Gan中的一系列CROSS JOIN。

WITH
L0   AS(SELECT 1 AS c UNION ALL SELECT 1),
L1   AS(SELECT 1 AS c FROM L0 AS A CROSS JOIN L0 AS B),
L2   AS(SELECT 1 AS c FROM L1 AS A CROSS JOIN L1 AS B),
L3   AS(SELECT 1 AS c FROM L2 AS A CROSS JOIN L2 AS B),
L4   AS(SELECT 1 AS c FROM L3 AS A CROSS JOIN L3 AS B),
L5   AS(SELECT 1 AS c FROM L4 AS A CROSS JOIN L4 AS B),
Nums AS(SELECT ROW_NUMBER() OVER(ORDER BY (SELECT NULL)) AS n FROM L5)
SELECT n FROM Nums

这为您提供了高达40亿的数字。

Answer 2

在#TableA中，如果您的临时表不包含标识符和行数超过1，我会在案例中添加Id

SELECT * INTO #TableA
FROM
(
 SELECT ROW_NUMBER() OVER (ORDER BY (SELECT 1)) AS Id,
        MIS_Request_Detail.vno, MIS_Request_Detail.IID
        , MIS_Request_Detail.Qty-MIS_Request_Detail.BalQty qty, 
        1 RcvdQty, pk,
        ItmMstr.IName, ItmMstr.UName, '' SrNo,
        MIS_Request_Detail.Qty As ReqQty, MIS_Request_Detail.BalQty
        , MIS_Request_Detail.Qty-MIS_Request_Detail.BalQty RemainQty
FROM MIS_Request_Detail INNER JOIN
  view_MIS_Item_Master ItmMstr ON ItmMstr.IID=MIS_Request_Detail.IID
WHERE ReqType=1 AND MIS_Request_Detail.vno=@vno 
) T

;WITH Nbrs(Id, vno, IID, IName, UName, SrNo, QTY, ReqDetpk, RcvdQty, ReqQty, 
           BalQty, RemainQty, Color, chked, Pk, isupdate, isdeleted, [Level]) AS (
SELECT A.Id, A.vno,A.IID, A.IName, A.UName, CAST(SrNo AS VARCHAR(50)) SrNo
       , CAST(N.Number AS varchar(50)) QTY, pk ReqDetpk, RcvdQty,
       A.ReqQty, A.BalQty, A.RemainQty, 0 Color,  0 chked, 0 Pk, 0 AS isupdate
       , '' AS isdeleted, 1 AS [Level]
FROM #TableA A
UNION ALL
SELECT A.Id, A.vno,A.IID, A.IName, A.UName, CAST(SrNo AS VARCHAR(50)) SrNo
       , CAST(N.Number AS varchar(50)) QTY, pk ReqDetpk, RcvdQty,
       A.ReqQty, A.BalQty, A.RemainQty, 0 Color,  0 chked, 0 Pk, 0 AS isupdate
       , '' AS isdeleted, n.[Level] + 1
FROM #TableA A JOIN Nbrs n ON A.Id = n.Id
WHERE A.Number > n.[Level]
)
SELECT *
FROM Nbrs
ORDER BY IID, N.Number, pk

如何根据sql中的选定数据集重复行

2 个答案: