SQL不能实现想要的结果。

[whzq007]

drop table ##a
drop table ##b

declare @i int, @rq1 char(10),@rq2 char(10),@s varchar(8000)   
  set @rq1 = '2008-05-01'   
  set @rq2 = '2008-08-01'  
  set @s   = 'select convert(char(7),dateadd(month,id,'''+@rq1   +'''),121) as xxx into ##a from     
  (select top '+cast(datediff(month,@rq1,@rq2)+1 as char(3)) + '(select sum(1) from sysobjects where name <= a.name) - 1 as id from sysobjects a) bb'   
  exec (@s) 
 
  select IDENTITY(int, 1,1) as id, 'select * from PUB..log_' + substring(xxx, 1, 4) + '_'  + substring(xxx, 6, 2) + ' union all ' as sSqlString into ##b from ##a
  update ##b set sSqlString = substring(sSqlString, 1, 30) where id = (select max(id) from ##b)

  select * from ##b
   
  set @s = ''

  select @i = max(id) from ##b

  while @i > 0   
  begin 
    select @s = @s + sSqlString from ##b where id = @i 
    set @i = @i - 1   
  end

  exec(@s)

生成的临时表#b的内容如下:
id	sSqlString
1	select * from PUB..log_2008_05 union all 
2	select * from PUB..log_2008_06 union all 
3	select * from PUB..log_2008_07 union all 
4	select * from PUB..log_2008_08

我是想将sSqlString字段中的每条记录串起来，得到select * from PUB..log_2008_05 union all select * from PUB..log_2008_06 union all select * from PUB..log_2008_07 union all select * from PUB..log_2008_08这样一条语句，然后放在exec(@s)中执行，但为何无法生成最后的那个@s呢。奇怪。

[zjcxc]

select @s = @s + sSqlString from ##b where id = @i
--> 改成下面的(1. 语句之间需要空格分开 2. 你是倒过来拼语句的, 所以拼字符串的写法也要倒过来)
select @s = sSqlString + ' ' + @s from ##b where id = @i

[让你望见影子的墙]

@i > 0  改为@i>=0

或者：
declare @s varchar(8000),@count int,@i int
select @s = '',@i=1
set @count=(select max(id) from tb)

  while @i <=@count
  begin 
  
select @s = @s +sSqlString+' '  from tb where id = @i 
    set @i = @i +1   
  end

print @s

select * from PUB..log_2008_08 select * from PUB..log_2008_07 union all select * from PUB..log_2008_06 union all select * from PUB..log_2008_05 union all