To answer this question, you need to understand the concept of a View.
A View is a virtual table that is derived from one or more tables in a database. It does not occupy data storage space as it does not store any data itself. Instead, it is a saved query that can be used to retrieve data from the underlying tables.
Let's go through each option to understand why it is correct or incorrect:
Option A) To protect some of the columns of a table from other users - This option is correct because a View can be used to restrict access to certain columns of a table, allowing users to see only the columns that they have permission to access.
Option B) Occupies data storage space - This option is incorrect because a View does not occupy any data storage space. It is just a virtual table that is created based on the underlying tables.
Option C) To hide complexity of a query - This option is correct because a View can be used to simplify complex queries. Instead of writing a complex query each time, users can create a View that encapsulates the complexity and provides a simplified interface to retrieve the desired data.
Option D) To hide complexity of calculations - This option is correct because a View can be used to encapsulate complex calculations. Users can create a View that performs the necessary calculations and presents the results in a simplified manner.
The correct answer is B) Occupies data storage space. This option is incorrect because a View does not occupy any data storage space.