select a from A where a not in (select a from B )
order by 
case when len(a) < 3 then 0
     when charindex('-',a) < 3 then 0
     when patindex('%^[0-9]%',substing(a,2,charindex('-',a)-2))>0 then 0
     else substing(a,2,charindex('-',a)-2) end

------解决方案--------------------
SQL code
select a from A where a not in (select a from B )
order by 
case when len(a) < 3 then 0
     when charindex('-',a) < 3 then 0
     when patindex('%^[0-9]%',substing(a,2,charindex('-',a)-2))>0 then 0
     else cacst(substing(a,2,charindex('-',a)-2) as int) end