Comparing Azure PostgreSQL Offerings

Azure Cosmos DB for PostgreSQL and Azure Database for PostgreSQL both provide deployment options that use a native PostgreSQL database engine but are designed for different purposes and vary in supported features and capabilities. The chart highlights notable similarities and differences.

Cosmos DB for PostgreSQL

Cosmos DB for PostgreSQL (previously Hyperscale) provides a scale-out deployment for compute-intensive applications, such as large, distributed databases supporting online e-commerce, where locating relevant data close to users is beneficial. It uses the PostgreSQL Citus extension, a popular add-on, that connects to Cosmos DB’s back-end and infrastructure to implementing sharding designs and coordinate the distribution of data and queries across a cluster of computers. Admins have little access to the underlying compute layer and are limited to the controls provided by Cosmos DB.

PostgreSQL Flexible Server

PostgreSQL Flexible Server uses Linux VMs and provides a deployment option that resembles an on-premises instance. It provides access to server-level features like maximum connections, shared buffer settings, and advanced failover configurations. It also allows developers to co-locate applications on the same server as the database or in the same availability zone to reduce latency and improve performance. Administrators have control over maintenance activities and can enable automated encryption for data both at rest and in transit.