Re: Join question
От | Williams, Travis L, NEO |
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Тема | Re: Join question |
Дата | |
Msg-id | AB815D267EC31A4693CC24D234F8291605A0C663@ACCLUST02EVS1.ugd.att.com обсуждение исходный текст |
Ответ на | Join question ("Williams, Travis L, NEO" <tlw@att.com>) |
Список | pgsql-general |
Sure.. if it works.. I'm just trying to not have to make multiple calls to the DB.. I'll try it out.. Thanks, Travis -----Original Message----- From: Thomas A. Lowery [mailto:tlowery@stlowery.net] Sent: Thursday, August 28, 2003 8:06 PM To: pgsql-general@postgresql.org Subject: Re: [GENERAL] Join question Does using a union count as one query? select a from tst_1 where b is null union select d from tst_2 t2 join tst_1 t1 on (t1.b = t2.c) where t1.b is NOT null On Thu, Aug 28, 2003 at 05:55:27PM -0400, Williams, Travis L, NEO wrote: > Question, > > I have a table (1) with 2 col (a & b) where b can sometimes be null. I > need a query that if B is null I get back the contents of A.. but if B > is not null I do a join on it and table (2) col c to get the contents > of table (2) col d.. I can do this in multiple queries.. but was > wondering if I could do it in 1. ---------------------------(end of broadcast)--------------------------- TIP 1: subscribe and unsubscribe commands go to majordomo@postgresql.org
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