but if you refresh the materialized view, thenthese changes are not pushed back to the master and the changes are lost in thematerialized view itself. Writeable materialized views are typically
Several views, such asDBA_MVIEW_DETAIL_PARTITION, detail which partitions are stale or fresh. Oracle does not rewrite against partial stale materialized views if partition change tracking on the changed table is enabled by the presence of join dependent expression in the materialized view. To suppo...
materialized view in oracle A materialized view is a database object that contains the results of a query. They are local copies of data located remotely, or are used to create summary tables based on aggregations of a table's data. Materialized views, which store data based on remote tables...
ORA-23515 错误表明在尝试删除表空间时,Oracle 数据库检测到该表空间中还有物化视图(Materialized Views)和/或其索引存在。物化视图是预计算并存储查询结果的数据库对象,它们通常用于提高复杂查询的性能。由于物化视图和它们的索引占用表空间,因此在删除表空间之前,必须首先处理这些对象。 2. 提供解决ORA-23515错误的一般...
Oracle can optimize a query that selects from the source of your materialized view in such a way that it instead reads from your materialized view. In situations where you create materialized views as forms of aggregate tables, or as copies of frequently executed queries, this can greatly speed...
By including CUBE andROLLUP in a Materialized View along with other GROUP BY results, more complete information is available for reduced- cost queries. Those present will learn how to create and use Materialized Views and how to use CUBE and ROLLUP tocreate more complete summaries.John Jay King...
Example syntax tocreate a materialized view in oracle: CREATEMATERIALIZEDVIEWMV_MY_VIEW 1. REFRESH FASTSTARTWITHSYSDATE 1. NEXTSYSDATE+1 1. ASSELECT*FROM; 1. 1. Oracle usesmaterialized views to replicate data to non-master sites in a replication environmentand to cache expensive queries in a ...
http://www.databasejournal.com/features/oracle/article.php/2192071/Materialized-Views-in-Oracle.htm http://blog.csdn.net/XIAOHUI_LIAO/archive/2007/08/27/1759990.aspx About MATERIALIZED VIEW LOG: http://download.oracle.com/docs/cd/B12037_01/server.101/b10759/statements_6003.htm#i2064649 ...
Oracle: Oracle 10gR2 一、物化视图概述 Oracle的物化视图是包括一个查询结果的数据库对像,它是远程数据的的本地副本,或者用来生成基于数据表求和的汇总表。物化视图存储基于远程表的数据,也可以称为快照。 物化视图可以用于预先计算并保存表连接或聚集等耗时较多的操作的结果,这样,在执行查询时,就可以避免进行这些耗...
Oracle: Oracle 10gR2 一、物化视图概述 在复制环境下,创建的物化视图通常情况下主键,rowid和子查询视图。 物化视图由于是物理真实存在的,故可以创建索引。 二、物化视图刷新 物化视图,根据不同的着重点可以有不同的分类: 1) 按刷新方式分:FAST/COMPLETE/FORCE ...