难题：为什么SQL SERVER合并字符串最多只能是256个字符，郁闷！
示例表：
create   table   #aa   (fsupname   varchar(10),fkpono   varchar(1000))
GO
insert   #aa   select   'a厂 ', 'po-234-ui-po '
union   all   select   'a厂 ', 'po-234-ui-po '
union   all   select   'a厂 ', 'po-234-ui-po '
union   all   select   'a厂 ', 'po-234-ui-po '
union   all   select   'a厂 ', 'po-234-ui-po '
union   all   select   'a厂 ', 'po-234-ui-po '
union   all   select   'a厂 ', 'po-234-ui-po '
union   all   select   'a厂 ', 'po-234-ui-po '
union   all   select   'a厂 ', 'po-234-ui-po '
union   all   select   'a厂 ', 'po-234-ui-po '
union   all   select   'a厂 ', 'po-234-ui-po '
union   all   select   'a厂 ', 'po-234-ui-po '
union   all   select   'a厂 ', 'po-234-ui-po '
union   all   select   'a厂 ', 'po-234-ui-po '
union   all   select   'a厂 ', 'po-234-ui-po '
union   all   select   'a厂 ', 'po-234-ui-po '
union   all   select   'a厂 ', 'po-234-ui-po '
union   all   select   'a厂 ', 'po-234-ui-po '
union   all   select   'a厂 ', 'po-234-ui-po '
union   all   select   'a厂 ', 'po-234-ui-po '
union   all   select   'a厂 ', 'po-234-ui-po '
union   all   select   'a厂 ', 'po-234-ui-po '
union   all   select   'a厂 ', 'po-234-ui-po '
union   all   select   'a厂 ', 'po-234-ui-po '
union   all   select   'a厂 ', 'po-234-ui-po '
union   all   select   'a厂 ', 'po-234-ui-po '
union   all   select   'a厂 ', 'po-234-ui-po '
union   all   select   'a厂 ', 'po-234-ui-po '
union   all   select   'a厂 ', 'po-234-ui-po '
union   all   select   'a厂 ', 'po-234-ui-po '
union   all   select   'a厂 ', 'po-234-ui-po '
union   all   select   'a厂 ', 'po-234-ui-po '
union   all   select   'a厂 ', 'po-234-ui-po '
union   all   select   'a厂 ', 'po-234-ui-po '
union   all   select   'a厂 ', 'po-234-ui-po '
union   all   select   'a厂 ', 'po-234-ui-po '
union   all   select   'a厂 ', 'po-234-ui-po '
union   all   select   'a厂 ', 'po-234-ui-po '
union   all   select   'a厂 ', 'po-234-ui-po '
union   all   select   'a厂 ', 'po-234-ui-po '
union   all   select   'a厂 ', 'po-234-ui-po '
union   all   select   'a厂 ', 'po-234-ui-po '
union   all   select   'a厂 ', 'po-234-ui-po '
union   all   select   'a厂 ', 'po-234-ui-po '
union   all   select   'a厂 ', 'po-234-ui-po '
union &n