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From: aoki@postgres.Berkeley.EDU (Paul M. Aoki)
To: Michael Reifenberger <root@rz-wb.fh-sw.de>
Cc: postgres@postgres.Berkeley.EDU
Subject: Re: Searching for empty String. 
Reply-To: aoki@postgres.Berkeley.EDU (Paul M. Aoki)
In-reply-to: Your message of Fri, 6 May 1994 01:49:34 +0200 (MET DST) 
	     <Pine.3.89.9405060148.A13380-0100000@rz-wb.fh-sw.de> 
Date: Thu, 05 May 94 17:19:46 -0700
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Michael Reifenberger <root@rz-wb.fh-sw.de> writes:
> Is the any way to retrieve empty (null) fields?

null is not the same as an empty string.

if your fields contain zero-length strings, the query you gave (where 
foo.bar = "") will retrieve them.

if your fields contain null, you should use the ISNULL and NOTNULL
keywords as documented in the manual.
--
  Paul M. Aoki  |  CS Div., Dept. of EECS, UCB  |  aoki@postgres.Berkeley.EDU
                |  Berkeley, CA 94720           |  ...!uunet!ucbvax!aoki

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