Debezium vs PgSync: What are the differences?

Introduction

Debezium and PgSync are both tools used for synchronizing and monitoring database changes in real-time. While they serve similar purposes, there are key differences that set them apart.

1. Data Sources: Debezium is designed to work with a variety of data sources, including MySQL, PostgreSQL, MongoDB, and SQL Server, while PgSync is specifically built for PostgreSQL databases. This means that Debezium can be used for heterogeneous data environments, whereas PgSync is focused solely on PostgreSQL.

2. Data Capture Method: Debezium uses the concept of database change logs, also known as CDC (Change Data Capture), to capture and propagate data changes. It monitors the database's transaction log or internal structures to extract and stream events representing the changes. On the other hand, PgSync relies on real-time triggers or polling mechanisms to capture and synchronize changes in PostgreSQL databases. This difference in data capture methods affects performance and adaptability to different database systems.

3. Event Streaming: Another difference lies in the way data changes are streamed. Debezium streams events using Apache Kafka, a distributed streaming platform, which allows for high-throughput and fault-tolerant data streaming. PgSync, on the other hand, streams changes directly to the destination database in real-time. This difference in event streaming mechanisms can impact scalability and integration with other systems.

4. Functionality: Debezium not only captures and streams database changes but also provides rich functionality for data integration, transformation, and enrichment. It offers advanced features like event filtering, schema evolution, data enrichment through connectors, and support for complex event processing. PgSync, on the other hand, focuses primarily on data synchronization without providing extensive data integration capabilities.

5. Deployment: Debezium is typically deployed as a standalone service or embedded within applications and requires a Kafka cluster for event streaming. It follows a distributed architecture and can be scaled horizontally to handle high volumes of data. On the contrary, PgSync is a lightweight command-line tool that can be easily executed and deployed on a single machine or server. This difference in deployment options makes Debezium more suitable for complex and scalable data synchronization scenarios.

6. Community and Ecosystem: Debezium is an open-source project with an active community and a growing ecosystem. It has a wide range of connectors and integrations with popular technologies like Apache Kafka and Apache Pulsar. PgSync, although open-source as well, has a smaller community and a more focused ecosystem due to its specific support for PostgreSQL.

In summary, Debezium is a versatile and feature-rich tool for capturing, streaming, and integrating data changes from multiple data sources, whereas PgSync is a lightweight and specialized tool specifically tailored for PostgreSQL database synchronization.