Database Management Systems Quiz

What is the primary data model used for data storage and processing?

• Network Model

• Object-Oriented Model

• Relational Model

• Hierarchical Model

In a relational data model, what do rows represent?

• Attributes

• Records

• Tables

• Schemas

What is a single row of a table called?

• Attribute

• Record

• Column

• Tuple

What describes the relation name and attributes in a relational database?

• Relation Instance

• Relation Schema

• Relation Key

• Attribute Domain

What is the purpose of key constraints in a relation?

• To enforce referential integrity

• To allow NULL values

• To identify tuples uniquely

• To define attribute domains

What type of integrity constraint ensures that every attribute has a specific range of values?

• Entity Constraints

• Referential Integrity Constraints

• Domain Constraints

• Key Constraints

What is a foreign key?

• A constraint that enforces data types

• A unique identifier for a table

• An attribute that can accept NULL values

• A column that references a primary key in another table

What is the result of a natural join?

• All tuples from the right table

• All tuples from the left table

• All tuples from both tables

• Only matching tuples with redundant columns removed

What does the select operation (σ) do in relational algebra?

• Combines two relations

• Selects tuples that satisfy a predicate

• Projects columns

• Renames a relation

What is the output of the union operation (∪)?

• A Cartesian product of two relations

• Only matching tuples from both relations

• All tuples from both relations without duplicates

• Tuples present in one relation but not the other