Part I is an informal introduction for new users.
Part II documents the SQL query
language environment, including data types and functions, as well
as user-level performance tuning. Every
PostgreSQL user should read this.
Part III describes the installation and
administration of the server. Everyone who runs a
PostgreSQL server, be it for private
use or for others, should read this part.
Part IV describes the programming
interfaces for PostgreSQL client
programs.
Part V contains information for
advanced users about the extensibility capabilities of the
server. Topics are, for instance, user-defined data types and
functions.
Part VI contains reference information about
SQL commands, client and server programs. This part supports
the other parts with structured information sorted by command or
program.
Part VII contains assorted information that may be of
use to PostgreSQL developers.
PostgreSQL is an object-relational
database management system (ORDBMS) based on
POSTGRES, Version 4.2,
developed at the University of California at Berkeley Computer Science
Department. POSTGRES pioneered many concepts that only became
available in some commercial database systems much later.
PostgreSQL is an open-source descendant
of this original Berkeley code. It supports a large part of the SQL
standard and offers many modern features:
- complex queries
- foreign keys
- triggers
- views
- transactional integrity
- multiversion concurrency control
Also, PostgreSQL can be extended by the
user in many ways, for example by adding new
- data types
- functions
- operators
- aggregate functions
- index methods
- procedural languages
And because of the liberal license,
PostgreSQL can be used, modified, and
distributed by everyone free of charge for any purpose, be it
private, commercial, or academic.
