Question

在这个TSQL CTE中，我试图建立一个递归的发票列表，从父版本开始，每个发票的版本为1。

With
  myList
  AS (Select 10000 as INVOICE, 3 as VER
      UNION ALL
      Select 20000 as INVOICE, 5 as VER
      UNION ALL
      Select 30000 as INVOICE, 8 as VER
      UNION ALL
      Select 40000 as INVOICE, 2 as VER)
 ,newList (Invoice, Ver)
  AS (Select
       L1.Invoice
      ,L1.Ver
      from
       myList L1
      UNION ALL
      Select
       L2.Invoice
      ,L2.Ver - 1 Ver
      from
       myList L2
      Join
       newList L3
       on L2.invoice = L3.Invoice and L2.VER = L3.VER
      Where
       L2.Ver > = 1 )
 Select * from newList order by INVOICE, VER desc

选择＆＃39; myList＆＃39;会给你：

Invoice Ver
10000   3
20000   5
30000   8
40000   2

我希望实现的目标是：

Invoice Ver
10000   3
10000   2
10000   1
20000   5
20000   4
20000   3
20000   2
20000   1
30000   8
30000   7
30000   6
30000   5
30000   4
30000   3
30000   2
30000   1
40000   2
40000   1

我尝试了很多变化（当然不是正确的！）但我能做的最好的就是只达到第二级...

Invoice Ver
10000   3
10000   2
20000   5
20000   4
30000   8
30000   7
40000   2
40000   1

感谢您一看！

Answer 1

你需要有一个递归CTE，在每个递归调用中需要递减ver列

With myList
AS 
(     Select 10000 as INVOICE, 3 as VER
      UNION ALL
      Select 20000 as INVOICE, 5 as VER
      UNION ALL
      Select 30000 as INVOICE, 8 as VER
      UNION ALL
      Select 40000 as INVOICE, 2 as VER
 )
 ,newList (Invoice, Ver)
  AS 
 (
    SELECT INVOICE, VER from myList
    UNION ALL
    SELECT INVOICE, VER-1 FROM newList
    WHERE VER >1
  )
  SELECT * FROM newList order by INVOICE, VER desc

CTE递归查询以填充序列

1 个答案: