[Database] Concept of View vs Divide and Conquer

Prelude

As a software engineer in the banking industry, I have the opportunity to access volumes of data in order to analyze customers’ transaction behavior. These days I’ve read a series of articles regarding Oracle database and would like share with you about an interesting concept of SQL, View. There are two reasons why I would like to edit this article. First of all, the concept of View largely reduces the complexity of expressing solutions of query languages in contexts. Secondly, it is essentially very similar to a concept, Divide and Conquer, which is mentioned in the computer science field. Lastly, it matters that developers could code elegantly with simple expressions to face complicated issues.

The Scene of “View”

In the beginning, many developers would read Oracle tutorial to figure out the exact definition of View in the database field as follows:

A view is a named query, which represents a logical, virtual table that behaves like a real query but does not store any data.

However, I dislike copying a definition from a certain tutorial because that does not meet my subject of expressing my learning experience of the concept. On the contrary, I would like to explain it in this way:

A view is equivalent to a piece of real query in essence as a virtual table. However, it is usually applied to simplify queries by replacing multiple layers of queries and does not store any data.