Aurora vs. Postgres: A Comprehensive Comparison

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When it comes to choosing a relational database management system (RDBMS) for your business, there are several options available. Two popular choices are Amazon Aurora and PostgreSQL (often referred to as Postgres). In this article, we will dive deep into the features, performance, scalability, and other aspects of Aurora and Postgres to help you make an informed decision for your specific needs.

1. Overview of Amazon Aurora:

Amazon Aurora is a relational database service offered by Amazon Web Services (AWS). It is designed to provide high performance, scalability, and availability while reducing the administrative overhead typically associated with managing databases. Aurora is compatible with MySQL and PostgreSQL and offers a range of features and optimizations.

2. Overview of PostgreSQL:

PostgreSQL, also known as Postgres, is an open-source relational database management system. It has been around for over three decades and has gained a reputation for its stability, reliability, and extensive feature set. Postgres is known for its robustness and adherence to SQL standards.

Now let's compare Aurora and Postgres based on various factors:

3. Performance:

Performance is a critical consideration when evaluating a database system. Aurora boasts high performance, thanks to its underlying architecture. It uses a distributed storage system that replicates data across multiple Availability Zones for enhanced durability and availability. Aurora's storage layer is designed for low-latency and high-throughput I/O operations, resulting in excellent performance for read-heavy workloads.

Postgres, on the other hand, delivers solid performance with a proven track record. It supports a wide range of indexing options and query optimization techniques, allowing developers to fine-tune their queries for optimal performance. Postgres also provides advanced features like parallel query execution, which can significantly speed up queries on multi-core systems.

4. Scalability:

Both Aurora and Postgres offer scalability options, but they differ in their approach. Aurora employs a distributed architecture, where data is automatically replicated across multiple instances, allowing it to scale both read and write workloads efficiently. It can automatically add replicas to handle increased traffic and automatically scale storage as your data grows.

Postgres, being a traditional RDBMS, requires manual intervention for scaling. It supports various techniques like sharding and replication, but the setup and management of these features require additional effort. Scaling Postgres requires careful planning and may involve application-level changes to accommodate the distributed nature of the solution.

5. High Availability:

Both Aurora and Postgres prioritize high availability and data durability. Aurora's distributed storage architecture ensures that data is replicated across multiple Availability Zones, reducing the risk of data loss. In the event of a failure, Aurora automatically fails over to a replica, minimizing downtime and ensuring high availability.

Postgres offers high availability through features like streaming replication and automatic failover. With the right configuration, Postgres can maintain a hot standby replica that can take over in case of a primary instance failure. However, setting up and managing replication in Postgres requires more manual configuration compared to Aurora's automated failover capabilities.

6. Ecosystem and Community Support:

Postgres benefits from a large and active open-source community. It has a vast ecosystem of extensions, plugins, and tools developed by the community, offering additional functionality and ease of use. The community actively contributes to the development and improvement of Postgres, ensuring a steady stream of updates and bug fixes.

Aurora, although compatible with PostgreSQL, has a more limited ecosystem compared to the broader PostgreSQL community. While it offers compatibility with popular PostgreSQL extensions, some extensions may require modifications to work with Aurora's specific features. However, being part of the AWS ecosystem, Aurora integrates well with other AWS services, providing a seamless experience for users already utilizing AWS infrastructure.

7. Cost :

Cost is a crucial factor when considering any database solution. Let's explore the cost aspects of Aurora and Postgres.

Aurora's pricing is based on instance size, storage usage, and data transfer. It offers different instance types to cater to various workload requirements, from small instances suitable for development environments to powerful instances designed for high-performance production workloads. Storage costs are based on the amount of data stored, and data transfer costs apply when transferring data in and out of the Aurora cluster.

Postgres, being an open-source database, is generally considered more cost-effective. It is free to use and does not impose any licensing fees. However, you need to consider the cost of managing and maintaining your Postgres infrastructure, including server hardware, storage, backups, and monitoring. Additionally, if you choose to use managed Postgres services provided by cloud providers, there may be associated costs based on usage and resource allocation.

When comparing the cost of Aurora and Postgres, it is essential to evaluate your specific requirements, anticipated workload and available resources to determine the most cost-effective option for your business.

8. Data Durability and Backup:

Data durability and backup are critical considerations to ensure the safety and availability of your data.

Aurora offers automatic backups with a 6-hour recovery point objective (RPO) and continuous incremental backups to Amazon S3, providing point-in-time recovery. Additionally, Aurora allows you to create read replicas that can serve as backups and offload read traffic, ensuring redundancy and improved availability.

Postgres provides various backup methods, including physical backups and logical backups using tools like pg_dump. Postgres backups can be scheduled and automated based on your requirements. With the right configuration, you can set up streaming replication and use a replica as a standby backup for disaster recovery.

9. Security:

Both Aurora and Postgres prioritize security and provide robust mechanisms to protect your data.

Aurora integrates with AWS Identity and Access Management (IAM), allowing you to manage user access and permissions using AWS IAM roles. It supports encryption at rest using AWS Key Management Service (KMS) and encryption in transit using SSL/TLS protocols. Aurora also offers enhanced VPC networking, allowing you to control network access to your database instances.

Postgres provides a range of security features, including role-based access control (RBAC), SSL/TLS encryption for data in transit, and support for encrypted connections using certificates. It also offers various authentication methods, including password-based authentication and integration with external authentication providers. Additionally, Postgres allows you to define fine-grained access control through its robust privilege system.

10. Use Cases:

Both Aurora and Postgres are suitable for a wide range of use cases, including web applications, e-commerce platforms, content management systems, and data-driven applications.

Aurora's performance and scalability make it an excellent choice for applications with high read and write workloads that require low-latency responses. Its compatibility with MySQL and PostgreSQL enables easy migration of existing applications to Aurora without significant code changes.

Postgres is known for its flexibility and extensibility, making it suitable for complex data models and applications that require advanced querying capabilities. Its extensive feature set, rich ecosystem of extensions, and adherence to SQL standards make it an ideal choice for applications that demand a high level of data integrity and consistency.

11. Replication Methods:

Aurora utilizes a proprietary replication method called Aurora Replicas. It replicates data across multiple instances within the Aurora cluster, enabling both high availability and read scalability. Aurora Replicas have a fast replica lag time, allowing them to provide near real-time replication. In addition, Aurora provides automated failover to a replica in the event of a primary instance failure.

Postgres supports various replication methods, including physical and logical replication. Physical replication involves replicating the entire database cluster, while logical replication replicates specific tables or sets of data. Postgres replication requires more manual configuration and management compared to Aurora's automated replication.

12. Locking Mechanisms:

Aurora implements a multi-versioning concurrency control (MVCC) mechanism, similar to other modern RDBMSs. MVCC enables concurrent read and write operations without blocking, improving performance in highly concurrent workloads. Aurora also uses optimistic locking techniques to handle conflicting writes.

Postgres utilizes a combination of row-level and predicate locking mechanisms for concurrency control. It employs a traditional concurrency model, where write operations can block concurrent read and write operations on the same data. Postgres also offers transaction isolation levels to control the locking behavior and ensure data consistency.

13. Monitoring and Management Tools:

Aurora provides monitoring and management tools specific to the Aurora platform. AWS CloudWatch allows you to monitor performance metrics, set alarms, and automate actions based on thresholds. Aurora also integrates with AWS Database Migration Service (DMS) for easy migration of databases to Aurora.

Postgres offers various monitoring and management tools tailored for PostgreSQL. Tools like pg_stat_activity and pg_stat_statements provide insights into query performance and resource utilization. Additionally, several third-party tools, such as pgAdmin and Datadog, offer comprehensive monitoring and management capabilities for Postgres.

14. Geographical Distribution:

Aurora Global Database is a feature that allows you to replicate an Aurora database across multiple AWS regions globally. It enables low-latency access to the database from different geographical locations, improving performance and providing disaster recovery capabilities.

Postgres can also be distributed across multiple geographical locations using techniques like logical replication or custom-built solutions. However, setting up and managing a globally distributed Postgres database requires additional configuration and maintenance compared to Aurora's integrated Global Database feature.

15. Transactional Consistency:

Aurora guarantees strict transactional consistency within an Availability Zone. It ensures that all reads within the same transaction see the same committed state of the database, providing ACID (Atomicity, Consistency, Isolation, Durability) compliance.

Postgres, by default, follows the principles of ACID compliance and ensures transactional consistency within a single database. However, in distributed scenarios with multiple replicas or sharded setups, maintaining transactional consistency across all nodes requires careful design and implementation.

It's important to consider these additional differences when evaluating Aurora and Postgres for your specific use case, as they can impact performance, data consistency, and management complexity.


Choosing between Aurora and Postgres depends on your specific requirements, budget, and expertise. Aurora offers a managed solution with high performance, scalability, and seamless integration with AWS services. On the other hand, Postgres provides a robust open-source database with a large community, extensive feature set, and cost advantages.

Written by
Soham Dutta


Aurora vs. Postgres: A Comprehensive Comparison