What is the difference between a view and a table in SQL?

A view in SQL is a virtual table based on the result-set of an SQL statement, unlike a table which is a structured set of data.

In SQL, a table is a basic unit of data storage that organises data into rows and columns. Each column in a table is designed to store a certain type of information, like numbers, texts, or dates. Each row, on the other hand, represents a single, implicitly structured data item in the table. Tables are used to store data that is logically grouped together, and they can be manipulated using SQL operations like SELECT, INSERT, UPDATE, DELETE, etc.

A view, however, is not a physical entity. It is a virtual table that is a result of a query on one or more tables. A view consists of rows and columns just like a table, but its data are defined by a query. Unlike a table, a view does not occupy physical space in the database. It is a set of references to data in tables, not a separate copy of the data. Views can be used to simplify SQL operations, provide an additional level of data abstraction, and restrict access to the data in the underlying tables.

The main difference between a view and a table is that views are definitions built on top of other tables (or views), and do not hold data themselves. If data in the underlying table changes, the same change is reflected in the view. A table, on the other hand, stores the data physically in the database.

In summary, a table is a structured set of data stored in a database, while a view is a virtual table created as a result of a query on one or more tables. They are both essential components in SQL, each serving different purposes in data management.