Can we have index on materialized view in Oracle?

Can we have index on materialized view in Oracle?

A materialized view can be partitioned, and you can define a materialized view on a partitioned table. You can also define one or more indexes on the materialized view.

How do you refresh data in materialized view?

1. Query Rewrite Method 1: Text Match Rewrite.
2. Query Rewrite Method 2: Join Back.
3. Query Rewrite Method 3: Aggregate Computability.
4. Query Rewrite Method 4: Aggregate Rollup.
5. Query Rewrite Method 5: Rollup Using a Dimension.
6. Query Rewrite Method 6: When Materialized Views Have Only a Subset of Data.

Do materialized views need to be refreshed?

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.

Where are Oracle materialized views stored?

Unlike an ordinary view, which does not take up any storage space or contain any data, a materialized view contains the rows resulting from a query against one or more base tables or views. A materialized view can be stored in the same database as its base tables or in a different database.

How do I make a materialized view read only?

Table of Contents

1. 1.2.1 Task 1: Evaluate the Database Server Hardware.
2. 1.2.2 Task 2: Install the Oracle Database Software.
3. 1.2.3 Task 3: Plan the Database.
4. 1.2.4 Task 4: Create and Open the Database.
5. 1.2.5 Task 5: Back Up the Database.
6. 1.2.6 Task 6: Enroll System Users.
7. 1.2.7 Task 7: Implement the Database Design.

How do you check if materialized view is refreshed?

select * from dba_refresh;select * from dba_refresh_children; select * from sys. v_$mvrefresh; Then below query to find the status of job.

How do you update a materialized view?

REFRESH MATERIALIZED VIEW

1. Name. REFRESH MATERIALIZED VIEW — replace the contents of a materialized view.
2. Synopsis. REFRESH MATERIALIZED VIEW name [ WITH [ NO ] DATA ]
3. Description. REFRESH MATERIALIZED VIEW completely replaces the contents of a materialized view.
4. Parameters. name.
5. Notes.
6. Examples.
7. Compatibility.
8. See Also.

How do I open a materialized view?

To view a materialized view:

1. On the Workspace home page, click SQL Workshop and then Object Browser. Object Browser appears.
2. From the Object list, select Materialized Views.
3. From the Object Selection pane, select a view. The Materialized View appears.

Can we update materialized view?

To update the data in a materialized view, you can use the REFRESH MATERIALIZED VIEW statement at any time. When you use this statement, Amazon Redshift identifies changes that have taken place in the base table or tables, and then applies those changes to the materialized view.

Why do we use materialized view in Oracle?

Oracle uses materialized 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 this Oracle9i Replicationmanual in general, discusses materialized views for use in a replication environment.

What is materialize hint in Oracle?

Note the use of the Oracle undocumented materialize hint in the WITH clause. The Oracle materialize hint is used to ensure that the Oracle CBO materializes the temporary tables that are created inside the WITH clause, and its opposite is the undocumented inline hint.

Can we use create or replace materialized view?

No, we can’t use create or replace option with materialised voews. To replace such views we must drop them first and recreate them.

Is materialized view refreshed automatically?

A materialized view can be refreshed automatically. It depends on how it was defined. If it was defined as refresh on commit, it is refreshed automatically, otherwise it is refreshed on some sort of schedule. A normal view is not refreshed automatically.