mv+mvlog实现数据迁移

源库(testdb)：
Drop Table test;
Create Sequence s_test;
Create Table test (Id Number,str Varchar2(100));
alter table TEST add constraint pk_test primary key (Id);
Insert Into test Select s_test.Nextval,tname From tab;
Create Materialized View Log On test;

目标库(db151)：
Drop Table test;
Create Table test As Select * From test@testdb Where 1=2;
Create Materialized View test On Prebuilt Table Refresh Fast As Select * From test@testdb;
Begin
  dbms_mview.refresh('TEST','Complete');
End;

源库(testdb)：
Insert Into test Select s_test.Nextval,tname From tab;

目标库(db151)：
Begin
  dbms_mview.refresh('TEST');
End;
Select Count(1) from test;

切换：
目标库(db151)：
Drop Materialized View test;

几个问题：
1、目标库表为Prebuilt Table时，不能写数据
2、源库表必须有主键