(Foundation of MySql) DBMS, Architecture, Data Models, Keys

What is the main purpose of a Database Management System (DBMS)?

• Creating spreadsheets

• Designing websites

• Managing data efficiently

• Sending emails

Answer explanation

A DBMS helps store, retrieve, and manage large amounts of structured data effectively, replacing file-based systems.

Which of the following is not a component of a DBMS?

• a) Query Processor

• b) Web Server

• c) Storage Manager

• d) Transaction Manager

Answer explanation

A Web Server is not part of the DBMS itself. It can access a DBMS, but it’s not an internal component.

Which of the following best defines a “schema”?

• The actual data in the database

• A blueprint or structure of the database

• The process of backing up data

• A type of key

Answer explanation

The schema defines how the database is structured — tables, relationships, data types, etc.

What is data independence in DBMS?

• Storing data outside the database

• Using data without any storage

• Ability to modify schema without affecting data

• Ability to copy data

Answer explanation

Data independence allows changes to the schema without needing to rewrite applications.

Which model uses entities and relationships?

• Hierarchical Model

• Relational Model

• Object Model

• Entity-Relationship Model

Answer explanation

The ER model uses entities and relationships to visually represent the data structure.

In a relational database, what is a “tuple”?

• A column

• A table

• A row

• A relationship

Answer explanation

In relational terms, each row is called a tuple — representing one record.

What is a primary key used for?

• Linking to another table

• Sorting data

• Uniquely identifying a record

• Allowing NULLs

Answer explanation

Primary keys are unique and ensure no two rows in a table have the same value in this field.

What is a foreign key?

• A key stored in another country

• A unique identifier

• A key that links to a primary key in another table

• A duplicate key

Answer explanation

A foreign key maintains referential integrity between two related tables.

What does the term normalization mean?

• Encrypting the database

• Organizing data to reduce redundancy

• Creating backups

• Improving server speed

Answer explanation

Normalization is the process of structuring a relational database to reduce data duplication.

What is an example of a logical level description in a DBMS?

• How files are stored on disk

• ER diagram

• Table names and columns

• Operating system used

Answer explanation

Logical level is about what data is stored and the relationships — not how or where it's stored.