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Old 02-16-11, 08:59
bobFROMaccount bobFROMaccount is offline
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Relational Algebra

Given : LIKE(person, course), TAKING(person, course), and DISLIKE(person, course). Also assume that a person likes at least one course and dislike at least one course as well. We also assume that a course is taken by at least one person.

List the people that are taking all the courses they like. Express in relational algebra.


I've spent a long time looking at this problem and cannot figure it out. I realize if there was one person, I can easily find most questions that ask "all" but in this case, I cannot figure it out because it is more than one person.


Thanks,
Bob From Accounting
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