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From: Richard Huxton <dev@archonet.com>
Organization: Archonet Ltd
To: Ajit Aranha <ajit_aranha@rocketmail.com>,
	pgsql-sql@postgresql.org
Subject: Re: Null not equal to '' (empty)
Date: Fri, 27 Sep 2002 13:36:03 +0100
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On Friday 20 Sep 2002 7:09 am, Ajit Aranha wrote:
>  Why is ''(empty) not equal to null? Its a major headache when porting
> from other RDBMS like Oracle. Anyone knows any easy workarounds?

By definition it is different - null means "not known" or "no value" not em=
pty=20
string. Do you think it should be zero for numbers?

> i.e. if you use:    create table tbl (
>                          c1 varchar(5));
> 		 insert into tbl values ('');
>                       select * from tbl where c1 is null;  will return
> zero rows.

Yep - that's the way it should be. If you want empty-strings, ask for them.=
 If=20
you don't want to allow null values in a column define it as NOT NULL.

- Richard Huxton