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From: hansene@hpcc01.HP.COM (Ed Hansen)
Newsgroups: comp.databases
Subject: Re: How do I get SQL (Unify 4.0) to pull all linked
Message-ID: <770006@hpcc01.HP.COM>
Date: 13 May 91 16:46:42 GMT
References: <1991May7.000450.1699@hrc.uucp>
Organization: HP Corp Computing & Services
Lines: 29

/ hpcc01:comp.databases / dan@hrc.uucp (Dan Troxel) /  5:04 pm  May  6, 1991 /

How do I get all records from table_1, even though some records in table_1
are not linked to table_2???

	select table_1.field_1, table_2.field_2 from table_1, table_2
	where table_1.field_1 = table_2.field_1

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What you need here is an 'Outer Join' and I don't think this is
available in Unify. In SYBASE , your query will be as follows :
	select table_1.field_1, table_2.field_2 from table_1, table_2
	where table_1.field_1 *= table_2.field_1


Another way of achieving this result is by using UNION (again not
supported by Unify ? ) as follows :

	select table_1.field_1, table_2.field_2 from table_1, table_2
	where table_1.field_1 = table_2.field_1

      union
	select table_1.field_1, NULL from table_1
	where table_1.field_1 not in (select table_2.field_1 
					from table_2)


JeanMarie (jeanmar@hpcc31.corp.hp.com)
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