ArangoDB vs Neo4j: What are the differences?

Introduction

ArangoDB and Neo4j are both popular graph databases that are used for managing and querying highly connected data. While they both serve similar purposes, there are key differences between the two.

1. Data Model: ArangoDB is a multi-model database that supports a combination of graph, document, and key-value data models. It allows users to store data in different structures and access them through a unified query language called AQL. On the other hand, Neo4j is a pure graph database that focuses solely on the graph data model. It provides a native graph storage and processing engine, enabling efficient management of relationships between nodes.

2. Scalability: ArangoDB is designed to scale horizontally across multiple machines through its cluster feature. It allows for automatic data distribution and replication, ensuring high availability and performance. Neo4j, on the other hand, has a master-slave replication model where a single server acts as the master and the others as slaves. This architecture limits the scalability of Neo4j compared to ArangoDB.

3. Query Language: ArangoDB uses its own query language called AQL, which is a declarative language inspired by SQL. AQL supports various graph traversal and manipulation operations along with document-oriented queries. Neo4j, on the other hand, uses a query language called Cypher, specifically designed for graph pattern matching and querying. Cypher's syntax is highly expressive and intuitive for working with graph data.

4. ACID Compliance: ArangoDB supports ACID (Atomicity, Consistency, Isolation, Durability) transactions at a document level, making it suitable for applications that require strong data consistency. Neo4j, on the other hand, focuses more on eventual consistency and allows for higher performance by relaxing some of the ACID constraints. This makes Neo4j a better choice for applications that prioritize scalability and performance over strict consistency.

5. Community and Ecosystem: ArangoDB has a growing community and a rich ecosystem with a wide range of integrations, tools, and libraries. It supports popular programming languages like JavaScript, Python, and Go, making it easier for developers to work with it. Neo4j, on the other hand, has been around for a longer time and has a more established community and ecosystem. It has a larger number of third-party integrations and a wealth of resources and documentation available.

6. Licensing: ArangoDB is available under both a free open-source license (Apache License 2.0) and a commercial license. This gives users the flexibility to choose the license that suits their needs. Neo4j also provides a free community edition under the GNU General Public License (GPLv3), but it requires purchasing a commercial license for production deployments. This difference in licensing can be a factor to consider depending on the requirements and budget of the project.

In summary, ArangoDB offers a multi-model database with support for graph, document, and key-value data models, scalable clustering, ACID compliance, and a flexible licensing model. Neo4j, on the other hand, is a pure graph database focused on the graph data model, with a powerful query language, robust community and ecosystem, and a different approach to consistency and scalability. Choosing between the two depends on the specific requirements and priorities of the project.