optpls: A C repository from sbahra

This is the source code for the Opt++ Extensible Optimizer.
The latest copy is available from
 <http://www.cs.wisc.edu/~navin/research/download>.
Documentation can be separately downloaded form the same site.

See the file "copyright" in this directory for the copyright notice.

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To compile:

	Goto the file Config.make. The first two lines will be as follows:

		BASE = /local.tom/optpls
		WISH = /s/std/bin/wish

	Change the value of BASE to the pathname of the directory
	in which you untarred opt++. (Its the directory in which
	this README file is located.)

	Change the value of WISH to the pathname where "wish"
	executable resides on your system. "wish" is a windowing
	shell that comes with the standard "tcl" distribution.
	This code has been tested with version 7.4 of Tcl.
	
	Make sure you have g++ 2.6.2 or better and
	that it is in your path.

	Now type
		% make all
	This should make the optimizer. 


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To run some examples try the following:

	Change directory to "bin".
	Run the command
		% opt 
n
Now type the some of the following queries.
the optimizer should print out an optimized access plan for
the query. (Of course, since the optimizer is not connected to a
real database system it does not execute any queries. It just reads
some dummy catalog information and statistics from a file called
".catalog" in the same directory.)

Example queries (remember to end a query with a semicolon):

	select name from Cities;

	select name, age from Cities where Cities.mayor.name = "Jose";

	select name, age 
        from Cities 
        where Cities.country.continent = "africa";


You can use "showplan" to see the access plan produced by the
optimizer in a nice tree format. Just run

	% opt | showplan

and type in the query followed by a semi-colon.
sbahra/optpls
