PostgreSQL Tutorial: Views

A view is a named query that provides another way to present data in the database tables. A view is defined based on one or more tables which are known as base tables. When you create a view, you basically create a query and assign a name to the query. Therefore, a view is useful for wrapping a commonly used complex query.

Note that regular views do not store any data except the materialized views. In PostgreSQL, you can create special views called materialized views that store data physically and periodically refresh data from the base tables. The materialized views are handy in many scenarios, such as faster data access to a remote server and caching.

In this section, you will learn about the PostgreSQL views concept and how to manage views, such as creating, modifying, and removing views from the database.

• Managing PostgreSQL views – introduce you to the concept of the view and show you how to create, modify, and remove PostgreSQL views.
• Drop view – learn how to drop one or more views from the database.
• Create updatable views – give you examples of creating updatable views that allow you to issue INSERT, UPDATE, and DELETE statements to update data in the base tables through the views.
• Materialized views – introduce you to materialized views and provide you with the steps of creating and refreshing data for materialized views.
• Creating updatable views using the WITH CHECK OPTION clause – show you how to use the WITH CHECK OPTION clause to check the view-defining condition when you make a change to the base table through the view.
• Create recursive views – introduce you to the recursive view and show you an example of creating a recursive view in PostgreSQL.