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From: dan@hrc.UUCP (Dan Troxel)
Newsgroups: comp.databases
Subject: Re: a question regarding a query using Unify 4.0 SQL
Message-ID: <201604@hrc.UUCP>
Date: 16 Aug 90 18:09:05 GMT
Organization: Handwriting Research Corp. - Phoenix, AZ
Lines: 18

>	select rolodex.entry_num from rolodex
>		where rolodex.referral_source = 'POST*'
>		and rolodex.entry_num ^=
>		select rolnotes.rol_linker from rolnotes/

How would the above know to select only null records, instead of all the
records found without that entrynum. Example:

	select rolodex.entry_num,rolnotes.rol_linker from rolodex,rolnotes
		where rolodex.referral_source = 'POST*'
		and rolodex.entry_num ^= rolnotes.rol_linker/
Newsgroups: comp.databases


-- 
Dan Troxel @ Handwriting Research Corporation                  WK 1-602-957-8870
Camelback Corporate Center  2821 E. Camelback Road  Suite 600  Phoenix, AZ 85016
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