materialized views for data replicationOne of the main functions of materialized views is for data replication, Oracle's advanced replication capabilities are divided into two parts, multi-master replication and materialized view replication. Materialized view replication is the function of materialized view. Materialized view replication contains only read-only view replication, updatable materialized view replication, and writable materialized view replication. 1. Only the read-only view replication is based on the reading-only environment of the source database. 2. Updatable materialized view replication establishes a two-way replication environment based on materialized views. 3. Writable materialized view replication uses for update when materialized views are established, but does not add to materialized view groups like updatable materialized views, so local materialized views can be modified, but modifications cannot be sent to the source database because the modifications are lost after the materialized view is refreshed. This type of materialized view replication is seldom used.7 replicating Data Using materialized viewsHttp://docs.oracle.com/cd/E11882_01/server.112/e17516/tdpii_reppit.htm#BEHBEBJAmaterialized views for precomputedThis type of materialized view is typically used in a data warehouse system. It is primarily used to pre-compute and save the results of more time-consuming operations such as table joins or aggregates, so that time-consuming operations can be avoided when queries are executed, and results are obtained quickly. This materialized view also frequently uses the query rewrite mechanism so that it does not need to modify the original query statements, and Oracle automatically chooses the appropriate materialized view for querying, completely transparent to the application. This materialized view can be divided into the following three types: a materialized view containing aggregates, a materialized view that contains only connections, and a nested materialized view. The limitations of the fast refresh of three materialized views are very different, but not the other way.
Oracle materialized view timed full refresh causes archive log surges http://www.2cto.com/database/201203/123878.html
O Use of Oracle materialized views