
	                     POSTGRES95 version 1.0

About Postgres95
----------------
Postgres95 is a derivative of the last official release of Postgres (version
4.2). The code has been ANSI-fied and trimmed by 25%. There are a lot of
internal changes that improve performance and code maintainability. Postgres95
runs about 30-50% faster on the Wisconsin Benchmark compared to v4.2. Apart
from bug fixes, these are the major enhancements:

  *  The query language POSTQUEL has been replaced with SQL (implemented in 
     the server). We do not support subqueries at the moment. (However,
     subqueries can be imitated with user defined SQL functions.) Aggregates 
     have been re-implemented. We also added support for GROUP BY. The libpq 
     interface is still available for C programs.  

  *  In addition to the monitor program, we provide a new program (psql)
     which supports GNU readline.
  
  *  We added a new front-end library, libpgtcl, that supports Tcl-based
     clients.  A sample shell, pgtclsh, provides four new Tcl commands 
     to interface tcl programs with the Postgres95 backend.

  *  The large object interface has been overhauled. We kept Inversion large 
     objects as the only mechanism for storing large objects. (This is
     not to be confused with the Inversion file system which has been
     removed.)

  *  The instance-level rule system has been removed. Rules are still 
     available as rewrite rules.

  *  A short tutorial introducing regular SQL features as well as those
     of ours is distributed with the source code.

  *  gmake (instead of BSD make) is used for the build. Also, Postgres95 can 
     be compiled with an unpatched gcc (data alignment of doubles has been 
     fixed).

Postgres95 is free and the complete source is available. It is subjected to
the copyright terms described in an accompanying file named "COPYRIGHT".
 
Platforms
---------
Postgres95 has been compiled and tested on Alpha (OSF 3.2), DECStation
(Ultrix 4.4), SPARC (SunOS 4.1.3), SPARC (Solaris 2.4), and HP 9000/700 
(HP-UX 9.0).

In addition, ports are provided for linux (Intel x86, 1.2 kernel
running ELF), BSD44_derived OS's (NetBSD, FreeBSD, BSD/OS), AIX 3.2.5,
SGI MIPS running IRIX 5.3.

Some ports are contributed efforts and have not been tested at
Berkeley by the authors due to unavailability of platforms.

A Windows NT port is in the works. Interested party should contact the authors
or Jon Forrest (forrest@cs.berkeley.edu).

Support
-------
The POSTGRES project has officially ended in 1994 and the POSTGRES group
no longer exist at Berkeley. Hence, there is no official support for
Postgres95. (However, the authors will be available for questions during
beta-testing.)

To join the postgres95@postgres.berkeley.edu mailing list, send a
message with "ADD" in the subject line to
	postgres95-request@postgres.berkeley.edu

This is an unmoderated mailing list for the discussion of postgres95
related issues.  Jolly and Andrew monitor the list closely but since 
postgres95 development is a volunteer effort, we cannot guarantee
timely responses to bug reports and questions.  

Information about postgres95 can also be found on our WWW home page:
	http://s2k-ftp.cs.berkeley.edu:8000/postgres95

If support is critical, you should consider a commercial product such as
Illustra (which is the commercial version of Postgres).

Contact
-------
If you have any other questions, please contact Jolly Chen
(jolly@CS.Berkeley.edu) or Andrew Yu (andrew@CS.Berkeley.edu).
