Re: What to call this operator?
From: Marshall Spight <marshall.spight_at_gmail.com>
Date: 29 Jun 2005 11:24:26 -0700
Message-ID: <1120069466.357430.273600_at_o13g2000cwo.googlegroups.com>
Date: 29 Jun 2005 11:24:26 -0700
Message-ID: <1120069466.357430.273600_at_o13g2000cwo.googlegroups.com>
One final note, reducing everything down to these 2.5 operations has another advantage, which is that it make key inference a lot simpler.
With join, all keys are preserved.
With meet, all the keys that were completely contained
in the remaining columns remain. If there are none, then
you get a single key that covers all the remaining columns.
Did I get that right?
Marshall Received on Wed Jun 29 2005 - 20:24:26 CEST