带UNION ALL物化视图的快速刷新
1. 定义的查询的union all操作必须在最顶等级（查询重写后）
2. 物化视图日志指定rowid和including new values
3. 如果表设涉及到一个大量的insert或者直接路径加载，deletes,update，指定sequencea
4. from列表中所有表的rowid必须出现在select子句中
5. select列中必须包括一个维护列，被称为union all marker
6. 远端数据库的表不支持union all
7. 不支持聚集操作，因为没有rowid
CREATETABLEtest1ASSELECT*fromdba_objects;
CREATETABLEtest2ASSELECT*fromdba_objects;
CREATETABLEtest3ASSELECT*fromdba_objects;
CREATEMATERIALIZEDVIEWLOGONCTAIS2.TEST1WITHROWID,SEQUENCEINCLUDINGNEWVALUES;
CREATEMATERIALIZEDVIEWLOGONCTAIS2.TEST2WITHROWID,SEQUENCEINCLUDINGNEWVALUES;
CREATEMATERIALIZEDVIEWLOGONCTAIS2.TEST3WITHROWID,SEQUENCEINCLUDINGNEWVALUES;
CREATEMATERIALIZEDVIEWmv_test_union_all
REFRESHFASTONDEMANDWITHROWID
AS
SELECTowner, object_name, subobject_name, object_id, data_object_id, object_type, created, last_ddl_time,TIMESTAMP, status,TEMPORARY,GENERATED, secondary,1marker,ROWIDrdfromtest1
UNIONALL
SELECTowner, object_name, subobject_name, object_id, data_object_id, object_type, created, last_ddl_time,TIMESTAMP, status,TEMPORARY,GENERATED, secondary,2marker,ROWIDrdfromtest2
UNIONALL
SELECTowner, object_name, subobject_name, object_id, data_object_id, object_type, created, last_ddl_time,TIMESTAMP, status,TEMPORARY,GENERATED, secondary,3marker,ROWIDrdfromtest3
带聚集物化视图的快速刷新
1. 物化视图日志指定rowid和including new values
2. 如果表设涉及到一个大量的insert或者直接路径加载，deletes,update，指定sequence
3. 支持的函数sum,count,avg,stddev,variance,min,max
4. 必须指定count(*)
5. 如果使用stddev,variance，那么count和sum必须指定。ORACLE推荐同时指定sum(expr*expr)
6. select中的列不能有来自多个表的复杂的
所谓出于job而胜于job，说的就是Oracle 10g后的新特性Scheduler啦。在10g环境中，ORACLE建议使用Scheduler替换普通的job，来管理任务的执行。其实，将Scheduler描述成管理job的工具已经太过片面了，10G版本中新增的Scheduler绝不仅仅是创建任务这么简单。。。。
提示：ORACLE中管理Scheduler是通过DBMS_SCHEDULER包，本章� ......
