2014-11-03 83 views
0

在此TSQL CTE中,我试图建立一个递归的以父版本开始的发票列表,每个发票的版本为1。CTE递归查询以填充序列

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 
     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 

上 'myList中' A选择会给你:

Invoice Ver 
10000 3 
20000 5 
30000 8 
40000 2 

而我希望达到的目标是:

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 

我尝试了许多变化(当然不是正确的!)但我能做的最好的只是实现第二级...

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

感谢您的光临!

回答

3

你需要有一个递归CTE为此,在每次递归调用需要递减ver

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 
+0

哈哈 - 以为我做你说的正是我需要做的。我想微软的例子让我失望了,因为CTE的两条腿都引用了锚点查询。无论如何,做得好! – flaZer 2014-11-03 19:58:27