PostgreSQL

Overview

PostgreSQL (often referred to as Postgres) is a free, open source relational database management system (RDBMS) known for its high reliability, rich functionality, and standard compliance. It supports the SQL standard (ANSI SQL) and provides advanced features such as JSON/NoSQL support, geographic information system (GIS) extensions, and full-text search. PostgreSQL runs on platforms such as Windows, Linux, and macOS, and is widely used in web applications, data analysis, and enterprise systems.

History and Development

• Origin:
  • PostgreSQL originated from the POSTGRES project in 1986, led by Michael Stonebraker of the University of California, Berkeley, to create the next generation of databases.
  • In 1996, the project was renamed PostgreSQL, adopted the SQL standard, and released the first open source version.
• Development History:
  • 2000-2010: Introduced multi-version concurrency control (MVCC), table partitioning, and triggers to enhance performance and functionality.
  • 2010-2015: Added JSON support (2012, version 9.2), full-text search and foreign key constraints to improve flexibility.
  • 2017: Released PostgreSQL 10, introduced logical replication and parallel query, and optimized big data processing.
  • 2023-2025: The latest version PostgreSQL 17 (released in September 2024), optimized JSON processing, incremental backup and query performance, and supported modern applications.
• Community and support:
  • Maintained by the global PostgreSQL community, hosted on postgresql.org and GitHub.
  • Active X community.
  • Enterprise support comes from Crunchy Data, EDB and AWS (RDS for PostgreSQL).
• Open source license: Adopts the PostgreSQL license (similar to the MIT license), free to use, allowing commercial and personal development.

Main Features

PostgreSQL is known for its reliability, scalability, and standards compliance, and is suitable for web development and data analysis. Here are its main features:

1. Relational and non-relational support
   • Relational database:
     • Supports tables, views, foreign keys, indexes, and triggers, and complies with the SQL:2016 standard.
     • Suitable for storing structured data.
   • Non-relational functions:
     • JSON/JSONB: Store and query unstructured data.
     • Full-text search: Support multi-language search.
     • PostGIS: Geographic information extension.
2. Multi-version concurrency control (MVCC)
   • Function:
     • Allow multiple users to read and write the database at the same time to avoid lock conflicts.
     • Use snapshot isolation, and read operations do not block write operations.
   • Performance:
     • PostgreSQL 17 optimizes MVCC, reduces vacuum overhead, and improves concurrent performance.
3. High reliability and data integrity
   • Transaction support:
     • Support ACID (atomicity, consistency, isolation, persistence) to ensure data consistency.
     • Use BEGIN, COMMIT, ROLLBACK to manage transactions.
   • Backup and recovery:
     • Support incremental backup (PostgreSQL 17) and logical replication, suitable for data migration.
     • Use pg_dump and pg_restore to back up the donation database.
4. Extensibility and customization
   • Extensions:
     • Support PostGIS, pg_trgm (fuzzy search), uuid-ossp (UUID generation) and other extensions.
     • Custom functions can be written (PL/pgSQL, Python).
   • Index:
     • Support B-tree, GiST, GIN and other indexes to optimize query speed.
5. Cross-platform and tools
   • Support systems: Windows, Linux, macOS.
   • Management tools:
     • pgAdmin: graphical management interface, manage tables and queries.
     • psql: command line tool, run SQL commands.

Advantages and limitations

Advantages

• Feature-rich:
  • Supports SQL and NoSQL (such as JSONB), suitable for mixed data.
  • Provides full-text search, PostGIS, etc.
• High reliability:
  • ACID transactions and MVCC ensure data consistency, suitable for high-concurrency scenarios.
  • PostgreSQL "enterprise-level stability".
• Open source and free:
  • PostgreSQL license is free, suitable for developers with limited budgets.
• Cross-platform:
  • Suitable for multi-platform development and deployment.
• Community and ecology:
  • Active community provides tutorials and support.
• Performance optimization:
  • PostgreSQL 17 improves query speed and backup efficiency.

Limitations

• Resource usage:
  • Compared with SQLite, PostgreSQL occupies more memory (about 500MB) and disk space.
  • Solution: Run on a device with 4GB+ RAM, or use a lightweight configuration.
• Learning curve:
  • Advanced features (such as JSONB, PostGIS) need to be learned, and SQL syntax is complex for novices.
  • Solution: Use pgAdmin to simplify operations, refer to the pgAdmin tutorial.
• Complex configuration:
  • Need to adjust postgresql.conf and pg_hba.conf to optimize performance or security.
  • Solution: Use the default configuration, or refer to the PostgreSQL documentation.
• Deployment cost:
  • The production environment requires cloud services (such as AWS RDS), which increases costs.
  • Solution: Local development, production deployment on cloud servers.
• Competitors:
  • MySQL is lighter, MongoDB is more suitable for NoSQL.
  • Solution: Choose PostgreSQL's JSONB and reliability.

Summary

PostgreSQL is a feature-rich, reliable open source relational database that supports SQL and NoSQL features and is suitable for Web development and data analysis. Its ACID transactions, MVCC, JSONB, and PostGIS extensions make it an ideal backend. PostgreSQL is better suited for structured data and hybrid scenarios than MySQL (faster but with fewer features) or MongoDB (NoSQL-specific).