What is a materialized view and how does it differ from a view in SQL?

What is a view in SQL?

Views are a special version of tables in SQL. They provide a virtual table environment for various complex operations. You can select data from multiple tables, or you can select specific data based on certain criteria in views.

CREATE VIEW view_name AS
SELECT column1, column2.....
FROM table_name
WHERE condition;        

What is a materialized view in SQL?

A materialized view in SQL is a special type of view that stores the result of a query in a physical table. Unlike a regular view, a materialized view does not update automatically when the underlying tables or views change. Instead, you have to refresh the materialized view manually or on a schedule using the REFRESH MATERIALIZED VIEW statement. For example, you can create a materialized view that shows the total sales by month from a table called orders:

How do views and materialized views differ?

The main difference between views and materialized views is that views are dynamic and materialized views are static. This means that views always reflect the latest data from the underlying tables or views, while materialized views only show the data from the last refresh.

How do you choose between views and materialized views?

It all depends on the data and the requirements. Views and Materialized Views in SQL are quite different from each other. Views are used when data is to be accessed infrequently and the data in a table gets updated on a frequent basis. In contrast, Materialized Views are used when data is to be accessed frequently and data in table not get updated on frequent basis. if your underlying data is large or changes frequently, if your queries are complex or run often, or if you want to create permanent or recurring queries. However, these are not hard and fast rules; you may find exceptions or trade-offs in some situations.