> For the complete documentation index, see [llms.txt](https://docs.postgresql.tw/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.postgresql.tw/11/qian-yan/1.-shi-mo-shi-postgresql.md).

# 1. 什麼是PostgreSQL？

PostgreSQL是基於POSTGRES 4.2的物件導向關連式資料庫管理系統，其由美國加州伯克萊大學資訊科學系所研發。POSTGRES所開發的許多重要概念成為許多日後商用資料庫系統重要的一部份。

PostgreSQL由伯克萊大學公開其原始碼所誕生，它支援了大多數的標準SQL語法，並提供許多先進的功能：

* complex queries
* foreign keys
* triggers
* updatable views
* transactional integrity
* multiversion concurrency control

同時，PostgreSQL也支援讓使用者能以自己的方式善用資料庫系統：

* data types
* functions
* operators
* aggregate functions
* index methods
* procedural languages

在使用權利方面，不論任何人以任何目的，使用、修改、散布PostgreSQL，都是被允許的，包含私人使用、商業用途、或學術研究。


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