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Re: Relational symmetric difference is well defined

From: Vadim Tropashko <vadimtro_invalid_at_yahoo.com>
Date: Fri, 15 Jun 2007 16:45:19 -0700
Message-ID: <1181951119.615693.101990@d30g2000prg.googlegroups.com> 





On Jun 15, 4:21 pm, "V.J. Kumar" <vjkm..._at_gmail.com> wrote:


> Sure,  second order lang. is more expressive,  but its expressivity does

> not come for free !




Something is not right here. So, join, union, and difference can be
defined via first order formulas, while relational division don't?
Sure relational division is expressible via join, union, and
difference!
Received on Fri Jun 15 2007 - 18:45:19 CDT












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