<!-- doc/src/sgml/history.sgml -->

<sect1 id="history">

<title>A Brief History of <productname>&productname;</productname></title>

<title>A Brief History of <productname>PostgreSQL</productname></title>

<indexterm zone="history">

<primary>history</primary>

<secondary>of&productname;</secondary>

<secondary>ofPostgreSQL</secondary>

</indexterm>

<para>

The object-relational database management system now known as

<productname>&productname;</productname> is derived from the

<productname>PostgreSQL</productname> is derived from the

<productname>POSTGRES</productname> package written at the

University of California at Berkeley. With over two decades of

development behind it, <productname>&productname;</productname> is now

development behind it, <productname>PostgreSQL</productname> is now

the most advanced open-source database available anywhere.

</para>

<acronym>SQL</acronym> (implemented in the server). (Interface

library <link linkend="libpq">libpq</link> was named after PostQUEL.)

Subqueries

were not supported until <productname>&productname;</productname>

were not supported until <productname>PostgreSQL</productname>

(see below), but they could be imitated in

<productname>Postgres95</productname> with user-defined

<acronym>SQL</acronym> functions. Aggregate functions were

</sect2>

<sect2>

<title><productname>&productname;</productname></title>

<title><productname>PostgreSQL</productname></title>

<para>

By 1996, it became clear that the name <quote>Postgres95</quote>

would not stand the test of time. We chose a new name,

<productname>&productname;</productname>, to reflect the relationship

<productname>PostgreSQL</productname>, to reflect the relationship

between the original <productname>POSTGRES</productname> and the

more recent versions with <acronym>SQL</acronym> capability. At

the same time, we set the version numbering to start at 6.0,

<para>

Many people continue to refer to

<productname>&productname;</productname> as <quote>Postgres</quote>

<productname>PostgreSQL</productname> as <quote>Postgres</quote>

(now rarely in all capital letters) because of tradition or because

it is easier to pronounce. This usage is widely accepted as a

nickname or alias.

The emphasis during development of

<productname>Postgres95</productname> was on identifying and

understanding existing problems in the server code. With

<productname>&productname;</productname>, the emphasis has shifted to

<productname>PostgreSQL</productname>, the emphasis has shifted to

augmenting features and capabilities, although work continues in

all areas.

</para>

<para>

Details about what has happened in <productname>&productname;</> since

Details about what has happened in <productname>PostgreSQL</> since

then can be found in <xref linkend="release">.

</para>

</sect2>

</sect1>

<para>

<productname>&productname;</productname> is an object-relational

database management system (<acronym>ORDBMS</acronym>) based on

database management system (<acronym>ORDBMS</acronym>) based on <ulink

url="http://postgresql.org"><productname>PostgreSQL</productname></ulink>, which is in turn based on

<ulink url="http://db.cs.berkeley.edu/postgres.html">

<productname>POSTGRES, Version 4.2</productname></ulink>,

developed at the University of California at Berkeley Computer Science

</para>

<para>

<productname>&productname;</productname> is an open-source descendant

<productname>PostgreSQL</productname> is an open-source descendant

of this original Berkeley code. It supports a large part of the SQL

standard and offers many modern features:

<date>2016</date>

<copyright>

<year>1996-2016</year>

<holder>The PostgreSQL Global Development Group</holder>

<year>2016</year>

<holder>Postgres Professional</holder>

</copyright>

<legalnotice id="legalnotice">

<title>Legal Notice</title>

<para>

<productname>PostgresPro</productname> is Copyright &copy; 2016 by the

Postgres Professional.

</para>

<para>

<productname>PostgreSQL</productname> is Copyright &copy; 1996-2016

by the PostgreSQL Global Development Group.

<title>&productname; &version; Documentation</title>

<bookinfo>

<corpauthor>The PostgreSQL Global Development Group</corpauthor>

<corpauthor>Postgres Professional</corpauthor>

<productname>&productname;</productname>

<productnumber>&version;</productnumber>

&legal;