What are Graph Databases?
Explore the fundamental differences between graph databases and traditional relational databases, and learn about their unique advantages.
What are Graph Databases? is a free Neo4j Graph Database Fundamentals lesson on CoddyKit — lesson 1 of 4. You can read the complete lesson below for free — then practise it hands-on in the browser with a built-in code editor and a 24/7 AI tutor. It is part of the Neo4j Graph Database Fundamentals learning path, one of 4 lessons in the course, and your progress syncs across the web and the CoddyKit app.
Welcome to Graph Databases!
Friend suggestions, fraud detection, recommendations — they all lean on graph databases. Let's see what makes them so good at connected data.
Relational Limits for Connections
Relational databases store data in tables, so connecting it means JOINs. As relationships deepen, those JOINs get slow and awkward to model.
The Simple Idea of a Graph
A graph is just two things: nodes (your entities) and relationships (how they connect). Think cities as nodes, roads as relationships.
Nodes: Your Data Points
A node is an entity — like a flexible table row. It carries labels to categorize it (:Person, :Product) and properties to describe it.
Relationships: How Things Connect
Relationships are the glue. Each one has a type and a direction (Alice FRIENDS_WITH Bob), and can carry properties of its own.
Properties: Rich Details
Properties are key-value details on nodes and relationships — name and age on a Person, quantity and price on a purchase. They make your graph expressive.
Graph vs. Relational: Connections
The key difference: relational connections need JOINs that cost more as they pile up. Graphs store relationships directly, so traversal stays fast — that's index-free adjacency.
Why Choose a Graph DB?
Why pick a graph database? Blazing queries on connected data, a flexible model, intuitive domain mapping, and easy discovery of hidden patterns.
Where Graphs Shine
Graphs shine wherever relationships are the point: social networks, recommendations, fraud detection, and IT dependency mapping.
Quick Check on Graph Basics
Let's test your knowledge of the fundamental components of a graph database.
Graph Database Summary
You've got the basics! Graphs use nodes and relationships, both carry properties, and they outshine relational DBs on connected data. Next up: Neo4j.
Frequently asked questions
Is the “What are Graph Databases?” lesson free?
Yes — the full text of “What are Graph Databases?” is free to read here on the web, and the Neo4j Graph Database Fundamentals course includes 4 lessons in total. To practise it interactively (a built-in code editor and a 24/7 AI tutor) and unlock the rest of the Neo4j Graph Database Fundamentals course, upgrade to CoddyKit PRO.
What will I learn in “What are Graph Databases?”?
Explore the fundamental differences between graph databases and traditional relational databases, and learn about their unique advantages. You practise Neo4j Graph Database Fundamentals with hands-on code you run directly in the browser, and a 24/7 AI tutor answers your questions as you work through the lesson.
Do I need any experience to start Neo4j Graph Database Fundamentals?
No prior experience is required. Neo4j Graph Database Fundamentals on CoddyKit is structured for beginners through advanced learners; this is — lesson 1 of 4, so you can start here or from the beginning and move at your own pace.
How long does the “What are Graph Databases?” lesson take?
Most CoddyKit lessons take about 5–10 minutes. Each one is bite-sized and interactive, so you make steady progress and pick up exactly where you left off across the web and the app.
Can I write and run code in this Neo4j Graph Database Fundamentals lesson?
Yes. Every Neo4j Graph Database Fundamentals lesson includes a built-in code editor, so you write and run real code right in your browser and get instant AI feedback — no local setup required.