How Apache AGE Works on Top of PostgreSQL
Tags: postgres, postgressql, apacheage, database
Published: 2023-08-27 11:37:46


## Introduction

Apache AGE is a PostgreSQL extension that provides graph database functionality. The goal of Apache AGE is to enable Postgres users to gain access to graph query modeling in Postgres, existing relational model. In this blogpost, I will explain how Apache AGE works on top of PostgreSQL and what benefits it brings to the users.

## What is a Graph Database?

A graph database is a type of database that stores data as nodes and edges, where nodes represent entities and edges represent relationships between them. A graph database allows users to query and analyze complex connected data using graph algorithms and traversal patterns. Graph databases are useful for applications that deal with social networks, recommendation systems, fraud detection, knowledge graphs, and more.

## Why Use Apache AGE?

Apache AGE is an extension for PostgreSQL that allows users to use graph data models within the database. It is built on top of the Apache Arrow format, which provides a high-performance, in-memory data structure for data processing. Apache AGE supports openCypher, one of the most popular graph query languages today, as well as SQL, the standard relational query language. Users can perform hybrid queries that combine both graph and relational data in a single query.

Some of the benefits of using Apache AGE are:

- Users can leverage the power and features of PostgreSQL

- Users can use existing relational data without going through migration or transformation. They can simply create graph views on top of the tables and query them as graphs.

- Users can benefit from the performance and scalability of Apache Arrow, which enables fast data transfer and computation between different systems and languages.

- Users can enjoy the flexibility and expressiveness of openCypher, which supports various graph operations such as pattern matching, aggregation, projection, filtering, ordering, and more.

## How Does Apache AGE Work?

Apache AGE works as a plugin for PostgreSQL that extends its functionality with graph features. It consists of three main components: the parser, the executor, and the storage engine.

1. The parser:
   It is responsible for parsing the user's queries and converting them into an internal representation that can be executed by the executor.

2. The executor:
   It is responsible for executing the queries and performing the graph operations. It uses Apache Arrow to store and manipulate the data in memory.

3. The storage engine:
   It is responsible for storing and retrieving the data from the underlying PostgreSQL tables. It uses a custom data type called agtype to store the graph data as JSONB objects.

The following diagram illustrates how Apache AGE works on top of PostgreSQL:


![Image showing how apache work on top of postgresql](https://dev-to-uploads.s3.amazonaws.com/uploads/articles/7soygfr66ncl8hvezmoi.png)


## How to install Apache AGE Extension?

To use Apache AGE, users need to install it as an extension for PostgreSQL. They can download the source code or binary packages from [the official website](https://age.apache.org) or [the GitHub repository](https://github.com/apache/age). 


## Conclusion

Apache AGE is a PostgreSQL extension that provides graph database functionality. It allows users to use graph data models within the existing relational database. It supports openCypher and SQL. 
It works as a plugin for PostgreSQL that extends its functionality with graph features. It consists of three main components: the parser, the executor, and the storage engine.