Question

Which of the following is called a database instance?

• A. Overall design of the database
• B. The snapshot of the database at any given time
• C. Data about the data
• D. Restriction on the type of data inserted

Answer 1

The Correct Option is B

(1) Overall design of the database: This refers to the database schema, not an instance. The schema is the blueprint that defines the structure of the database.

(2) The snapshot of the database at any given time: This is the correct definition of a database instance. It represents the actual data contained in the database at a specific moment in time, including all current records and their values.

(3) Data about the data: This describes metadata, which is information about the structure and properties of the data, not the instance itself.

(4) Restriction on the type of data inserted: This refers to data constraints or validation rules, which are part of the database schema definition.

Therefore, the correct answer is (2) The snapshot of the database at any given time, as this is what constitutes a database instance.