您应该只能执行插入,然后删除并重新插入。
create table t1
( id int, f1 int, f2 int);
create table t2
( id int primary key IDENTITY , f1 int, f2 int);
insert into t1 (id, f1, f2) values (null, 1, 2);
insert into t1 (id, f1, f2) values (null, 3, 4);
insert into t1 (id, f1, f2) values (null, 5, 6);
insert into t1 (id, f1, f2) values (null, 5, 6);
insert into t2 (f1, f2)
select f1, f2 from t1 where id is null;
delete t1
from t1 join t2 on (t1.f1 = t2.f1 and t1.f2 = t2.f2);
insert into t1
select id, f1, f2 from t2;
select * from t1;
请参阅此示例SQLFiddle http://sqlfiddle.com/#!3/2e630/1.