What is the purpose of a database view?

The purpose of a database view is to simplify complex queries by representing the result of a database query. A view essentially acts as a virtual table that is built on the result set of a specific SQL query. This means that users can interact with and access complex data in a more straightforward manner without needing to repeatedly write complex JOIN operations or nested queries each time they need a particular dataset.

For instance, if you frequently need to retrieve specific columns from multiple tables while also applying certain filters, you can create a view. This view will encapsulate that logic, allowing you to select data effortlessly by simply querying the view, rather than rewriting all of the underlying SQL logic every time. This not only saves time but also enhances data security, as views can limit the data a user can see.

In contrast, a view is not a mechanism for data backup and restoration, nor is it a permanent table. Instead, it is a dynamic representation of data that draws from one or more underlying tables. While views can reflect changes to the underlying data, they do not automatically update in the sense that they serve to preserve historical data or backup states; rather, they display the most current data available based on the original query but do not hold data themselves.