LICENSE

 版权声明

PostgreSQL 使用PostgreSQL版权声明，它是类似BSD的版权。由于这个经 OSI认证的版权不限制PostgreSQL在商业环境和有 版权的应用程序中使用，因此被公认为是非常有灵活性和对商业应用是友好的。加上有多个公司的支持和源代码归属公共所有， 我们的版权使得PostgreSQL在那些希望在自己的产品里嵌入数据库的厂商中很流行，因为他们不用担心费用、嵌入软件的版权 锁以及版权条款的改变。

英文原版版权声明
License


PostgreSQL is released under the PostgreSQL License, a liberal Open Source license, similar to the BSD or MIT licenses. 
PostgreSQL Database Management System (formerly known as Postgres, then as Postgres95) 
Portions Copyright (c) 1996-2013, The PostgreSQL Global Development Group 
Portions Copyright (c) 1994, The Regents of the University of California 
Permission to use, copy, modify, and distribute this software and its documentation for any purpose, without fee, and without a written agreement is hereby granted, provided that the above copyright notice and this paragraph and the following two paragraphs appear in all copies. 
IN NO EVENT SHALL THE UNIVERSITY OF CALIFORNIA BE LIABLE TO ANY PARTY FOR DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES, INCLUDING LOST PROFITS, ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN IF THE UNIVERSITY OF CALIFORNIA HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 
THE UNIVERSITY OF CALIFORNIA SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. THE SOFTWARE PROVIDED HEREUNDER IS ON AN "AS IS" BASIS, AND THE UNIVERSITY OF CALIFORNIA HAS NO OBLIGATIONS TO PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS. 

Why not the GNU General Public License? 
People often ask why PostgreSQL is not released under the GNU General Public License. The simple answer is because we like our license and do not want to change it. If you are keen to read more about this topic, then please take a look in the Archives at any of the many threads on this subject, but please don't start yet another debate on the subject!