Which Database Should You Choose? PostgreSQL, MySQL, SQL Server, Oracle, MongoDB and MariaDB
Compare PostgreSQL, MySQL, Microsoft SQL Server, Oracle, MongoDB and MariaDB by workload, OS, hardware, security, HA, licensing and operations.
What does this guide solve?
Database selection should not be based on benchmark speed alone. Data model, transactions, query patterns, team skills, licensing, HA/DR, security and growth model must be considered together.
When PostgreSQL stands out
PostgreSQL is a strong candidate for complex SQL, robust transactions, relational plus semi-structured JSONB data, advanced indexing and vendor-independent open-source deployments.
It is widely used on Linux and supports a broad set of CPU/OS combinations. RAM and low-latency SSD/NVMe become increasingly important as the active data set grows.
When MySQL / MariaDB fit
MySQL is common for web applications, SaaS, e-commerce, CMS and classic OLTP workloads. Correct InnoDB memory and I/O configuration can deliver strong transactional performance.
MariaDB is relevant for MySQL-derived ecosystems and open-source strategies, but application compatibility should be tested because the platforms have diverged over time.
When Microsoft SQL Server fits
SQL Server is a natural choice where .NET, Microsoft identity/tooling, existing T-SQL/BI dependencies and SQL Server skills are already strong.
Current SQL Server versions run on Windows and supported Linux distributions; Linux platform and filesystem support should be validated for the exact version.
When Oracle Database fits
Oracle remains strong for large enterprise applications, Oracle application dependencies, advanced HA/DR requirements, vendor certification and organisations with deep Oracle expertise.
The decision includes licensing, support, certified OS/hardware and operating cost—not only database features.
When MongoDB fits
MongoDB is strong for document-oriented workloads where application objects map naturally to JSON-like documents and schemas evolve frequently.
Replica sets, sharding and horizontal scaling are core strengths; heavily relational join/transaction workloads may still fit relational databases more naturally.
Decision matrix
Complex transactional SQL: PostgreSQL, SQL Server or Oracle. Web/SaaS OLTP: PostgreSQL, MySQL or MariaDB. Microsoft ecosystem: SQL Server. Oracle application dependency: Oracle. Flexible documents and horizontal scale: MongoDB.
Validate the final choice with realistic data, queries, backup/restore targets, HA scenarios and security requirements.
Frequently Asked Questions
Can one database be right for every workload?
Usually not. Organisations may use multiple engines for different workloads, but standardization is important to control operational complexity.
Which database is fastest?
There is no universal winner. Schema, queries, indexes, memory, storage latency, concurrency and configuration determine results.
Are open-source databases suitable for enterprise use?
PostgreSQL, MySQL and MariaDB can support large production environments; success depends on architecture, skills, support, HA and backup quality.
Evaluate Your Database Infrastructure
We can review workload, security, hardware, HA and backup requirements together.