select a.id,
       a.info,
       b.edit
from ta a,tb b 
where a.id=b.aid
and b.id=(select max(Id)
          from tb
          where aid=b.aid)

------解决方案--------------------
SQL code
select a.id,
       a.info,
       b.edit
from a inner join b on a.id=b.aid
where b.id=(select max(Id)
          from b
          group by aid)

------解决方案--------------------
select
A.id,B.aid,B.edit
from A
inner join B on B.aid = A.id
where B.id in (select max(id) from B group by aid)

------解决方案--------------------

SQL code
select
   a.id,a.info,b.edit
from
  a,b t
where
  a.id=t.bid
and
  not exists(select 1 from b  where aid=t.aid and id>t.id)

------解决方案--------------------
SQL code
--表A
--id info
--1 aa
--2 cc
--3 dd
--表B
--id aid edit  
--1 1 2   
--2 1 3
--3 2 1
--4 1 4
--5 2 3
--6 3 2
 if OBJECT_ID('表A')is not null
 drop table 表A
 go
 create table 表A (id int, info varchar(20))
 insert into  表A values(1, 'aa')
 insert into  表A values(2, 'cc')
 insert into  表A values(3, 'dd')
  if OBJECT_ID('表B')is not null
 drop table 表B
 go
 create table 表B (id int,aid int,edit INT)
insert into  表B values( 1, 1 ,2   )
insert into  表B values(2, 1 ,3 )
insert into  表B values(3 ,2, 1)
insert into  表B values( 4 ,1, 4)
insert into  表B values(5, 2, 3 )
insert into  表B values(6 ,3 ,2 )
--期望结果
--id info edit
--1 aa 4
--2 cc 3
--3 dd 2

select a.*,(select max(edit) from 表B where a.id=aid )edit from 表A a
 

id          info                 edit
----------- -------------------- -----------
1           aa                   4
2           cc                   3
3           dd                   2

(3 行受影响)

------解决方案--------------------
select A.id,A.info,B.edit
from A,B
where A.id=B.aid
and B.id in(select max(id)  
         from b
         group by b.id)