In the previous article, we covered MySQL — a reliable and popular leader in the world of relational databases. Today we turn to its main competitor, often called “the world’s most advanced open-source relational database” — PostgreSQL. Known for its strict SQL compliance, extensive feature set, and remarkable extensibility, PostgreSQL stands out among relational systems.

What is PostgreSQL?

PostgreSQL is a powerful, open-source (BSD-licensed) object-relational database management system (ORDBMS). It began as the POSTGRES project at the University of California, Berkeley in 1986 and was renamed PostgreSQL in 1996. Unlike purely relational systems, PostgreSQL incorporates object-oriented concepts, making it more flexible and powerful.

PostgreSQL strictly adheres to SQL standards, offers a wide range of advanced features, and is known for its stability and reliability.

PostgreSQL in Action: Key Use Cases and Scenarios

Thanks to its advanced capabilities and robustness, PostgreSQL is a go-to choice for more complex and demanding projects:

1. Complex Enterprise and Financial Systems:

   • Use Case: Storing mission-critical data where integrity and transaction reliability are vital.
   • How PostgreSQL Works: Its strict support for ACID transactions and high reliability make it ideal for banking, accounting, ERP, and CRM systems, where even minimal data loss is unacceptable.
   • Advantage: Superior data integrity and advanced reliability features.

2. Geographic Information Systems (GIS):

   • Use Case: Storing and analyzing spatial data.
   • How PostgreSQL Works: With the powerful PostGIS extension, PostgreSQL becomes one of the best databases for geographic data, supporting complex spatial queries.
   • Advantage: Exceptional capabilities for handling maps, coordinates, and regions.

3. Web Applications with Demanding Logic:

   • Use Case: Developing high-performance, complex web services that need not just speed, but also flexibility and advanced DB features.
   • How PostgreSQL Works: Widely used with web frameworks (like Django, Ruby on Rails, Node.js with Sequelize/TypeORM), where its extensibility and support for JSONB and complex types are valued over MySQL.
   • Advantage: Support for complex data types (arrays, JSONB), custom functions, indexes.

4. Data Warehousing and Analytical Systems:

   • Use Case: Analyzing large volumes of data and running complex analytical queries.
   • How PostgreSQL Works: Its query planner, support for window functions, materialized views, and parallel query execution make it suitable for business analytics.
   • Advantage: Powerful analytics capabilities.

5. Applications with Hybrid Data Models:

   • Use Case: When both relational and non-relational data (e.g., JSON, XML) need to be handled together.
   • How PostgreSQL Works: The JSONB data type allows storing and indexing JSON documents directly in relational structures, blending NoSQL flexibility with SQL reliability.
   • Advantage: No need for a separate NoSQL DB to manage JSON data.

Pros of PostgreSQL: 👍

• Strict SQL Standards Compliance: PostgreSQL has one of the most complete implementations of SQL, ensuring compatibility and predictability.
• Advanced Functionality: Includes features like window functions, recursive queries, materialized views, common table expressions (CTEs), and full-text search.
• Object-Relational Nature: Supports custom data types, functions, operators, and aggregates, expanding database capabilities.
• Powerful JSONB Handling: Indexing and fast querying of JSON document content.
• Exceptional Extensibility: A rich ecosystem of extensions (e.g., PostGIS for geodata, TimescaleDB for time-series) adds new functionality without altering the core.
• Reliability and Data Integrity: High-level ACID transaction support, multiversion concurrency control (MVCC) for efficient parallel query processing without locks.
• Advanced Query Optimizer: Efficient execution of complex queries.
• Fully Open Source: Developed by an active community and not owned by a commercial entity, reducing business risk.

Cons of PostgreSQL: 👎

• Higher Learning Curve: Its advanced features and flexibility can make setup and optimization more difficult for beginners compared to MySQL.
• Resource Consumption: Historically, PostgreSQL could consume more RAM than MySQL under similar loads (though modern versions are much more optimized).
• Less Common in Basic Hosting: MySQL is still more widely offered on cheap shared hosting plans, though this is changing.
• Write Scalability: Horizontal scaling for writes (sharding) requires more complex architectural approaches than read replication.

Conclusion

PostgreSQL is the choice for those seeking a powerful, reliable, extensible, and standards-compliant relational database. It’s ideal for critical business applications, complex logic systems, GIS platforms, and analytical workloads. If your project demands maximum data integrity, flexibility with data types (including JSONB), and deep customization potential, PostgreSQL is likely your top contender — surpassing MySQL in these areas.

In the next article, we’ll explore SQLite — a unique database that lives directly inside your application.