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Message-ID: <39726A5C.B6B45856@kss.net.au>
Date: Mon, 17 Jul 2000 12:07:25 +1000
From: Carolyn Lu Wong <carolyn@kss.net.au>
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To: "pgsql-sql@postgresql.org" <pgsql-sql@postgresql.org>
Subject: SQL question
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I have table with the following definition:

	create table table1(
		account_no	int4,
		start_date_tme	datetime
		....
	);

The table may contain null values for start_date_time.

When I run the following SQL query, it fails:

	select * from table1
	where start_date_time::date >= '01/01/2000'::date 
	and start_date_time::date <= '01/01/2001'::date;

I get error message 'Unable to convert null datetime to date.

It's fine if I run the same SQL query with added condition as follows:

	select * from table1
>	where account_no = 1
	and start_date_time::date >= '01/01/2000'::date 
	and start_date_time::date <= '01/01/2001'::date;

Is this a bug? Or there's an logical explaination for this?