What is PostgreSQL?
PostgreSQL is an advanced, open-source object-relational database management system (ORDBMS). Since it is open-source, its source code is freely available under the PostgreSQL license, which allows anyone to use, modify, and share it without restrictions. PostgreSQL is known for its stability and reliability, which means it requires very little effort to maintain compared to many other database systems.

• PostgreSQL (often called Postgres) is an open-source, powerful, and advanced relational database management system (RDBMS).
• It is based on the SQL standard (Structured Query Language) but goes beyond traditional SQL with additional features.
• PostgreSQL is often called “The world’s most advanced open-source database” because it supports modern data types, transactions, and high scalability.

Why PostgreSQL? (Why use it instead of others like MySQL, Oracle, SQL Server)

• Free & Open Source - No license fees.
• Standards Compliant - Follows ANSI SQL but extends it with modern features.
• Reliability & ACID Transactions -  Ensures data integrity (Atomicity, Consistency, Isolation, Durability).
  • Atomicity - Either the entire transaction happens, or none of it does.
  • Consistency - The database must always remain in a valid state before and after the transaction.
  • Isolation - Multiple transactions running at the same time do not interfere with each other.
  • Durability - Once a transaction is committed, the changes are permanent — even if the system crashes.
• Performance & Scalability - Handles small apps and huge enterprise-level systems.
• Extensibility - We can create custom functions, operators, and even new data types.
• Community Support - Large active community and lots of extensions.

History of PostgreSQL

• PostgreSQL, also known as Postgres, started as an academic project at the University of California, Berkeley.
• It was led by Professor Michael Stonebraker, who first worked on an earlier database system called Ingres.
• In 1982, he started a new project called POSTGRES (short for “Post-Ingres”) to solve the problems of existing databases.
• The goal was to create a system that could handle new data types and complex relationships more effectively than traditional relational databases.
• Over time, the POSTGRES project evolved into what we now know as PostgreSQL.
• PostgreSQL grew through open-source contributions, making it one of the most reliable and advanced database systems in the world.
• For his contributions, Michael Stonebraker received the Turing Award in 2014 (the highest honor in computer science).

What is PostgreSQL used for?

PostgreSQL can be used in many domains:

• Web Applications: As the backend database for apps (e.g., Django, Node.js, .NET, Java).
• Business Applications: For ERP, CRM, and large enterprise systems.
• Data Analytics / Data Warehousing: It supports complex queries, indexing, and big data.
• Geospatial Applications: With PostGIS extension, it’s widely used in maps, GIS, and location-based apps.
• Machine Learning & AI Integration: Can handle JSON, NoSQL-like queries, and store unstructured data.