What Is PostgreSQL?
PostgreSQL is an open-source relational database management system (RDBMS) known for SQL standards support, transactional reliability, extensibility, and advanced data types. It stores structured data in tables made of rows and columns, while constraints and relationships help preserve correctness.
PostgreSQL supports transactional workloads, analytical queries, JSON data, full-text search, geospatial extensions such as PostGIS, and custom functions and types. It is not simply a place to store records: it provides mechanisms for consistency, concurrency, access control, recovery, and query optimization.
Note
PostgreSQL is commonly shortened to Postgres. SQL is the query language; PostgreSQL is the database system.
Basic SQL query
SELECT current_database(), current_user, version();💡 This query reports the connected database, current database role, and PostgreSQL server version. It is a useful first check after connecting to a server.
Key Takeaways
- PostgreSQL is an RDBMS with advanced SQL capabilities.
- Tables represent structured data as rows and columns.
- Constraints and transactions help protect data integrity.
Knowledge Check
What is PostgreSQL?