Question

我有一个问题如果我有一行看起来像这样

|ordernumber|qty|articlenumber|
|  123125213| 3 |fffff111     |

如何将其拆分为三行，如下所示：

|ordernumber|qty|articlenumber|
|  123125213| 1 |fffff111     |
|  123125213| 1 |fffff111     |
|  123125213| 1 |fffff111     |

/ J

Answer 1

您可以使用递归CTE：

WITH RCTE AS 
(
    SELECT  
        ordernumber, qty, articlenumber, qty AS L
    FROM Table1

    UNION ALL

    SELECT      
        ordernumber, 1, articlenumber, L - 1 AS L
    FROM RCTE
    WHERE L>0
)
SELECT  ordernumber,qty, articlenumber
FROM RCTE WHERE qty = 1

<强> SQLFiddleDEMO

修改根据Marek Grzenkowicz的回答和MatBailie的评论，全新的想法：

WITH CTE_Nums AS ( SELECT MAX(qty) n FROM dbo.Table1 UNION ALL SELECT n-1 FROM CTE_Nums WHERE n>1 ) SELECT ordernumber , 1 AS qty, articlenumber FROM dbo.Table1 t1 INNER JOIN CTE_Nums n ON t1.qty >= n.n

生成从1到最大（数量）的数字并在其上连接表。

<强> SQLFiddle DEMO

Answer 2

这是一个快速入侵，使用一个附加表，其中填充了适合您期望的qty值的行数：

-- helper table
CREATE TABLE qty_splitter (qty int)

INSERT INTO qty_splitter VALUES (1)
INSERT INTO qty_splitter VALUES (2)
INSERT INTO qty_splitter VALUES (3)
INSERT INTO qty_splitter VALUES (4)
INSERT INTO qty_splitter VALUES (5)
....

-- query to produce split rows
SELECT t1.ordernumber, 1, t1.articlenumber
FROM table1 t1
INNER JOIN qty_splitter qs on t.qty >= qs.qty

Answer 3

您可以使用CTE

执行此操作

declare @t table (ordername varchar(50), qty int)

    insert into @t values ('ord1',5),('ord2',3)

    ;with cte as
    (
        select ordername, qty, qty-1 n
        from @t
        union all
        select ordername, qty, n-1
        from cte
        where n>0
    )
    select ordername,1
    from cte
    order by ordername

Answer 4

您还可以在master..spt_values系统表中使用选项。

SELECT t.ordernumber, o.qty, t.articlenumber
FROM dbo.SplitTable t CROSS APPLY (
                                   SELECT 1 AS qty
                                   FROM master..spt_values v
                                   WHERE v.TYPE = 'P' AND v.number < t.qty
                                   ) o

但是，为此目的，最好使用自己的序列表

请参阅SQLFiddle

上的演示

根据列拆分2行或更多行上的行

4 个答案: