What is on commit refresh?

ON COMMIT Refresh A materialized view can be refreshed automatically using the ON COMMIT method. Therefore, whenever a transaction commits which has updated the tables on which a materialized view is defined, those changes are automatically reflected in the materialized view.

What is fast refresh on commit?

If it is ON COMMIT , the refresh is performed at commit time of the transaction that does DML on the materialized view’s detail table. If you specify REFRESH FAST , Oracle performs further verification of the query definition to ensure that fast refresh can be performed if any of the detail tables change.

How can materialized view refresh automatically in Oracle?

Here, we specify that the materialized view will be refreshed every two hours with the refresh fast option. Instead of using DBMS_MVIEW, you can automatically refresh the MVIEW (Snapshot) using Oracle DBMS_JOB Management. Create the optimizer statistics and refresh the materialized view. Test the materialized view.

What is Materialised views in Oracle?

A materialized view is a database object that contains the results of a query. The FROM clause of the query can name tables, views, and other materialized views. Collectively these objects are called master tables (a replication term) or detail tables (a data warehousing term).

What does DBMS_MVIEW refresh do?

DBMS_MVIEW. REFRESH: Refreshes one or more Oracle materialized views.

What is DBMS_MVIEW refresh?

Refreshing materialized views To refresh the Oracle materialized view, call one of the procedures in DBMS_MVIEW. The DBMS_MVIEW package provides three types of refresh operations: DBMS_MVIEW. REFRESH: Refreshes one or more Oracle materialized views.

How often is materialized view refresh?

Unlike indexes, materialized views are not automatically updated with every data change. They must explicitly be refreshed, either on every commit, on a periodically time schedule or – typically in data warehouses – at the end of an ETL job.

How do I grant a materialized view privilege?

The privileges required to create a materialized view should be granted directly rather than through a role. To create a materialized view in your own schema: You must have been granted the CREATE MATERIALIZED VIEW system privilege and either the CREATE TABLE or CREATE ANY TABLE system privilege.

Can we automate refresh of materialized views?

You can set autorefresh for materialized views using CREATE MATERIALIZED VIEW. You can also use the AUTO REFRESH clause to refresh materialized views automatically.

How do I stop a materialized view from refreshing?

A materialized view created with the automatic refresh can not be alter to stop refreshing. In order to disable that you must break the dbms_job that was created in order to refresh the view. Mview are local copies of data located remotely, or are used to create summary tables based on aggregations of a table’s data.