--测试
declare @s varchar(8000)
set @s=''
select @s=@s+','''+a+''','''+b+''','''+c+''''
from(
select a='A',b='B',c='C'
union all select 'A','D','E'
union all select 'A','R','T'
union all select 'A','T','U'
) a
set @s=substring(@s,2,8000)
exec('select '+@s)
/*--结果
---- ---- ---- ---- ---- ---- ---- ---- ---- ---- ---- ----
A B C A D E A R T A T U