What is mean by Materialzed view
What is mean by Materialzed view
materialised view is also called the snapshot,schema,and also store in remoteside and also refresh time to time auto.we can call only query not any others.
A view is stored as a query in data dictionary. Whenever we execute that view, it takes data from base table using that query in data dictionary.
A materialised view along with query, it also store the results of the query in the database.
- A materialised view allow you to maintain copies of remote data on your local node.
- Materialized views, which store data based on remote tables are also, know as snapshots.
- After updation of base table materialized view data does not match with base table data. Data in materialized views must be refreshed to keep it synchronized with its base table.
Materialised views are like snapshots.
It is used to store the data locally from a remote database.
There are following refresh types like
Fast
Complete
Force
Materialized view is an object created by the developer or DBA for a report
or complex querry which fetches lots of data from multiple tables by joining them in a given querry.
People may ask why don't use view rather Materialized view, view is data dictionary but where as MV is an object and is locally managed, so the data
stored in MV is fast retrieval. But it wont automatically does not reflect the data whenever the data changed in database. DBA has to set the command to refresh MV on time to time basis.
What is private cursor and what is dynamic cursor ?
>>what is dynamic cursor ?
A cursor whose contents can be changed dynamically at run time are called dynamic cursors.
We use ref cursor datatype to create dynamic cursors.