delete A from B,A where A.某一字段=B.某一字段
insert into B
 select * from A 
 where not exists(select 1 from B where 某一字段=A.某一字段)

------解决方案--------------------
SQL code

--delete B
delete B from B,A where A.某一字段=B.某一字段
insert into B
 select * from A 
 where not exists(select 1 from B where 某一字段=A.某一字段)

------解决方案--------------------
+1
探讨

SQL code

--delete B
delete B from B,A where A.某一字段=B.某一字段
insert into B
 select * from A 
 where not exists(select 1 from B where 某一字段=A.某一字段)


------解决方案--------------------
SQL code
update b set col1=a.col1 .... from a join b on a.关联字段=b.关联字段 

insert into b select * from a where not exists(select 1 from b where 关联字段=a.关联字段)