Question

我正在使用SQL Server 2008.我有一个表temp：

select * from temp

返回：

name    start_limit   end_limit
-------------------------------
j       2             7
t       1             9

现在我想要生成以下序列

name    allowed values
----------------------
j       2
j       3
j       4
j       5
j       6
j       7
t       1
t       2
t       3
t       4
t       5
t       6
t       7
t       8
t       9

我该怎么办？

Answer 1

这将完美地运作：

;with a as(
select name,start_limit as [allowed values] from temp
union all
select b.name,a.[allowed values]+1 as [allowed values] from temp b inner join a on b.name=a.name and b.end_limit>a.[allowed values]
)
select * from a order by name,seq;

Answer 2

以下是使用计数表的一种方法，不需要递归

;WITH E1(N) AS (
                 SELECT 1 UNION ALL SELECT 1 UNION ALL SELECT 1 UNION ALL
                 SELECT 1 UNION ALL SELECT 1 UNION ALL SELECT 1 UNION ALL
                 SELECT 1 UNION ALL SELECT 1 UNION ALL SELECT 1 UNION ALL SELECT 1
                ),                          --10E+1 or 10 rows
       E2(N) AS (SELECT 1 FROM E1 a, E1 b), --10E+2 or 100 rows
       E4(N) AS (SELECT 1 FROM E2 a, E2 b), --10E+4 or 10,000 rows max
cteTally(N) AS (SELECT ROW_NUMBER() OVER (ORDER BY (SELECT NULL)) FROM E4)
SELECT a.name,c.N
FROM   ctetally c
       JOIN Yourtable a
         ON c.N BETWEEN a.start_limit AND a.end_limit

从SQL Server 2008表中的起始值和结束值创建序列？

2 个答案: