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Views in SQL a sample Query for your project

A view is basically a logical view of one or more base tables. A view can be a read only or updatable. A view generally be created to avoid any unwanted changes into actual base tables. Mainly view is created for security reasons.
  • A view can be constructed with another view so it is called as nested view.
  • You can create or replace an existing view
  • A view can be created without having base tables. This is possible with FORCE option.
Learn SQL and handle databases confidently
Learn SQL and handle databases confidently
Read only views: The standard syntax for view is as follows:


How to use FORCE command:


Updatable Views: A view can also be updatable if a view follows certain rules. Read more to understand all about what is updatable view.  
  • A view when it is created for update purpose, you can give INSERT,UPDATE and DELETE
  • A read only view should contain WITH READ ONLY CLAUSE.
While updating a view, it is possible to update only one base table at a time. When you created a view from more than one table, then it is not possible to update two tables at a time.

What is ALTER view
This is possible with CREATE OR REPLACE statement. Just you can replace with existing statement.

Drop view

Last pointsA view with CHECK OPTION is surely help you to satisfy certain condition. Usually this option will be used in updatable views.


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