普通租户(Oracle 模式) SQL 语句 DDL CREATE MATERIALIZED VIEW 更新时间:2025-01-17 14:56:41 描述 该语句用来创建物化视图。 物化视图是一种特殊类型的数据库对象,它存储查询结果的副本,并定期刷新(也可以手动刷新)以保持数据的最新状态。物化视图可以包含聚合,连接和子查询等操作,并且可以被索引和
To migrate large datasets efficiently, you can use Oracle materialized view replication. With replication, you can keep the target tables synchronized with the source tables. Thus, you can switch over to Amazon RDS later, if needed. Before you can migrate using materialized views, make sure that...
With AWS DMS, you can create and manage materialized views in Oracle and PostgreSQL databases to improve query performance and enable efficient data access. A materialized view is a database object that stores a pre-computed result set from a query, providing fast access ...
Before Oracle 8i, such materialized views were called snapshots. Materialized views include all the features that were available with snapshots and more. In this book, we will only focus on the application of materialized views to data warehousing. A materialized view is created using the CREATE ...
In data warehouses, materialized views normally contain aggregates. TheDWA_tables in the defaultOracle Communications Data Modelare this type of materialized view. For a materialized view with aggregates, for fast refresh to be possible: TheSELECTlist must contain all of theGROUP BYcolumns (if pr...
Materialized Views may be refreshed in the same manner used for Snapshots allowing summarization to occur with a frequency that meets the needs of the user community. By including CUBE andROLLUP in a Materialized View along with other GROUP BY results, more complete information is available for ...
Oracle Materialized Views Containing Joins Only 介绍 只包含表连接而没有聚合的物化视图。与聚合类似,表连接也是相当消耗资源的操作,将其结果预先计算并存储于物化视图中,可以提高SQL执行效率。 每一个基表(包括inline view)的Rowid必须出现在物化视图的select部分。这也是该物化视图可以快速刷新的必要条件之一。其他...
Although in Oracle Database 11g, analytic workspaces can now also take advantage of materialized views and query rewrite. Firstly we need to get a better appreciation of these two features within the database. Throughout the white paper, it is assumed that the reader is familiar with data ...
Oracle usesmaterialized views(also known as snapshots in prior releases) to replicate data to non-master sites in a replication environment and to cache expensive queries in a data warehouse environment. This chapter, and thisOracle9i Replicationmanual in general, discusses materialized views for use ...
在Oracle数据库中,哪个后台进程刷新物化视图(materialized views)? A 答案 答案:Oracle数据库使用Job Queue进程去运行用户的Jobs,经常在批量模式下。任务是用户自定义的预订运行一次或者多次的作业。比如说,可以使用一个Job队列去安排在后台运行的一个长时间运行的更新任务。给定一个开始时间和间隔时间,任务队列进程就会...