资 源 简 介
The Relational Algebra project:
includes an interactive interpreter that can perform relational algebra operations.
self contained and standalone, does not require a connection to a database
implements a re-usable Java class that models relations and relational operators.
provides static methods that can parse relational algebra expressions and evaluate them against relations.
About the author: http://uk.linkedin.com/pub/nick-everitt/24/296/67/
The idea behind the Relational Algebra project is that it is easier to understand relational algebra if you can experiment with the different operators. I looked at some of my solutions and thought "if only I could just run this with some test data to see if it works".
The interpreter handles select, project, join, divide, rename, union, difference, intersection, alias and times.
Update 27th September 2012: Version 0.3 now allows
