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Selectivity

From: GoranG <no_at_spam.net>
Date: Wed, 30 Apr 2003 10:24:09 +0100
Message-ID: <1v4vavk5ci76ci13d0d4n0v4l68157l4jg@4ax.com> 





Could someone, please, shed some light on why for selectivity (s)
defined as the ratio of the number of tuples that satisfy the
condition to the total number of tuples in the relation, and hence a
number between 0 and 1, it is often (allways?) said that high
selectivity corresponds to low value of this ratio and low selectivity
corresponds to the high value of such ratio ?!



( GoranG79 AT hotmail.com )
Received on Wed Apr 30 2003 - 04:24:09 CDT












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