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What is PostgreSQL

PostgreSQL is a powerful, free relational database that stores data in tables and answers questions written in SQL.

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  1. What is PostgreSQL

What is PostgreSQL

PostgreSQL (often called Postgres) is an open-source object-relational database known for reliability, standards compliance and rich features such as JSONB, arrays, window functions, full-text search and extensions like PostGIS.

It uses MVCC for concurrency and supports ACID transactions. Note: the editor on this site runs SQL on SQLite, whose syntax is mostly compatible, so a few PostgreSQL-only features are shown as psql sessions instead.

Note: PostgreSQL was created at UC Berkeley and has been developed for over 30 years.

Example: What is PostgreSQL

bash
postgres=# SELECT version();
                                          version
--------------------------------------------------------------------------------------------
 PostgreSQL 16.2 (Debian 16.2-1.pgdg120+2) on x86_64-pc-linux-gnu, compiled by gcc 12.2.0
(1 row)

postgres=# SELECT 'Hello, PostgreSQL!' AS greeting;
      greeting
--------------------
 Hello, PostgreSQL!
(1 row)

⚠️ Run this in your own terminal or Node.js environment.

Related Topics
{# common_mistakes/chapter_summary/browser_support: on Hindi pages the view already swaps in the hi_ translation fields (or blanks these out if untranslated), so this renders correctly for both languages without a lang_code check here. #}
Common Mistakes
  1. Confusing PostgreSQL with MySQL syntax
  2. Assuming it is only for large companies
  3. Ignoring that it needs a server process
Chapter Summary
  • PostgreSQL is an open-source relational database
  • It supports ACID transactions
  • It has rich types like JSONB and arrays
  • It is extensible with extensions
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