From the course: GraphRAG Essential Training

What is a graph database? - Neo4j Tutorial

From the course: GraphRAG Essential Training

Start my 1-month free trial Buy for my team

What is a graph database?

“

- [Narrator] So what exactly is a graph database? It's a type of database designed to store and work with relationships between data in a natural way. Unlike traditional databases which focus on storing data in rows and columns, graph databases focus on how things are connected. In a relational database like SQL, you store data in tables and define connections. You often need joins, which can slow things down as your data grows. Graph databases, on the other hand, store relationships directly, making it faster to find and analyze connections. Think about if you have a database of friends, where each row represents one person who's friends with another person. If you wanted to find all friends of a friend in a relational database, you would have to write a complex query with multiple joins. In a graph database, you just follow the connections, like tracing a path on a map, which is much faster and easier. Unlike relational databases where connections are inferred through foreign keys and joins, graph databases store relationships directly as part of the data. This really speeds up your queries because the database doesn't have to compute connections. So instead of searching through massive lists of data-defined connections, graph databases use index-free adjacency, meaning each node knows exactly which node it's linked to. This is especially fast as your graph grows bigger. Another great thing about graph databases is that the structure is schema flexible, meaning you don't have to define strict table relationships in advance. You can just add new node types and relationships as needed, making graph databases ideal for evolving and complex data models. So you see how graph databases make it easier to store, query, and analyze relationships between data. Instead of forcing data into rigid tables, they let connections work the way they do in real life, which is why they're becoming so important in AI and modern applications.

Contents