Azure SQL Database vs PostgreSQL

Azure SQL Database is a cloud-native relational database service built on the SQL Server engine and delivered as a fully managed PaaS. Microsoft manages provisioning, patching, backups, monitoring, and high availability. The service supports standard T-SQL and can be accessed through the Azure portal, SQL Server Management Studio, Visual Studio Code's MSSQL extension, and compatible application frameworks. It supports native JSON and REST and GraphQL APIs through Data API builder. Hyperscale independently scales compute and storage and supports scale-out with up to 30 named replicas. For AI application development, it offers native vector search and connections to Azure OpenAI and Azure AI Search. It can connect to Azure Functions and replicate SQL data into Microsoft Fabric for near-real-time querying and analysis. Security and governance include a multilayered approach with Microsoft Defender for SQL; recovery features include disaster recovery and snapshot-based backups. The free offer allows up to 10 General Purpose databases per subscription, each with 100,000 vCore seconds, 32 GB of data, and 32 GB of backup storage monthly. Once limits are reached, a database can auto-pause or remain online with excess use billed at standard rates.

PostgreSQL is a free, open-source database system for storing and scaling complex data workloads. It uses SQL and adds object-relational capabilities, with support for primitive and structured values as well as documents, geometric data, and custom types. Its supported formats include JSON/JSONB, XML, arrays, ranges, and UUIDs. For data integrity, it provides keys, constraints, locks, transactions, savepoints, and SQL-standard transaction isolation levels. Performance tools include multiple index types, query planning and optimization, parallel processing, partitioning, just-in-time expression compilation, and asynchronous I/O. Recovery and availability features include write-ahead logging, several replication methods, point-in-time recovery, and active standbys. Security options include multiple authentication methods, access controls, row- and column-level security, and multi-factor authentication. Extensions, procedural languages, and foreign data wrappers can connect PostgreSQL to other databases or streams. It runs on Linux, macOS, and Windows, and is self-hosted; no managed service is listed. The PostgreSQL License permits use, copying, modification, and distribution without a fee, subject to its conditions.