------一个有意思的题目-----------

请教各位：

数据记录是这样的

1

2

3

4

5

12

17

18

19

20

25

请问sqlserver2000如何显示成这样1-5，12，17-20，25



declare @t table(num int)

insert into @t select 1

union all select 2

union all select 3

union all select 4

union all select 5

union all select 12

union all select 17

union all select 18

union all select 19

union all select 20

union all select 25

select

rtrim(a.num)+(case when min(b.num)!=a.num then '-'+rtrim(min(b.num)) else '' end)

from

(select t.num from @t t where not exists(select 1 from @t where num=t.num-1)) a,

(select t.num from @t t where not exists(select 1 from @t where num=t.num+1)) b

where

a.num<=b.num

group by
a.num
/*

-------------------------

1-5

12

17-20

25

*/