Types of databases (relational, NoSQL, object-oriented) in DBMS Theory - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is a relational database?

A relational database stores data in tables with rows and columns. Each table has a unique key, and tables can be linked using these keys. It is like a spreadsheet where data is organized and easy to find.

beginner

What does NoSQL stand for and what is its main feature?

NoSQL means 'Not Only SQL'. It stores data in flexible ways like documents, key-value pairs, or graphs instead of tables. It is good for handling large or changing data quickly.

intermediate

How does an object-oriented database store data?

An object-oriented database stores data as objects, like in programming. Each object contains data and actions. It is useful when data is complex and related to real-world objects.

beginner

Name one advantage of relational databases.

Relational databases are good at keeping data organized and consistent using rules called constraints. They make it easy to search and join data from different tables.

intermediate

Why might someone choose a NoSQL database over a relational one?

NoSQL databases are chosen when data changes often or is very large. They can handle many users and different data types faster and more flexibly than relational databases.

Which type of database stores data in tables with rows and columns?

A NoSQL database

B Relational database

C Object-oriented database

D Graph database

Relational databases organize data in tables with rows and columns.

What is a key feature of NoSQL databases?

A Strict table structure

B Uses only SQL queries

C Flexible data storage formats

D Only stores numbers

NoSQL databases store data in flexible formats like documents or key-value pairs.

Which database type stores data as objects with both data and actions?

A Hierarchical

B NoSQL

C Relational

D Object-oriented

Object-oriented databases store data as objects containing data and methods.

Which database type is best for handling large, changing data quickly?

A NoSQL

B Relational

C Object-oriented

D Flat file

NoSQL databases are designed for large and rapidly changing data.

What is a common use of relational databases?

A Organizing data with clear relationships

B Handling unstructured data

C Storing complex objects with methods

D Storing data without any structure

Relational databases organize data with clear relationships using tables.

Explain the main differences between relational, NoSQL, and object-oriented databases.

Think about how data is organized and accessed in each type.

When would you choose a NoSQL database instead of a relational database?

Consider the nature and size of the data.