Date data types and NULL or ZERO (Dave Browne)

[fernando.olmos at hpa.com.au]

I agree. NULL and 0 are not date values in their own right. In Oracle
RDB, from memory a "zero" date is actually 18-Jan-1858 or something old
like that. SQL queries had to actually refer to that date as meaning
ZERO date. We never had to use NULL comparisons. In VB using ADO we
found that a recordset referring to a date field (i.e.:
rs.field!processed_date for example) could yield a NULL or a numeric. So
we had routines specifically created to verify that the date field had
an actual date value and not something else. I think it's funny that
maybe in the "colonial" days of programming, developers could not
comprehend a field that had nothing in it, so it either had to have 0 or
something.

----------------------------------------------------------------------

Message: 1
Date: Wed, 5 Oct 2005 23:56:41 +0100
From: "Dave Browne" <daveb at thyme-it.ie>
Subject: RE: Date data types and NULL or ZERO
To: <fernando.olmos at hpa.com.au>, <powerh-l at lists.sowder.com>
Message-ID: <200510052353755.SM02652 at ASDCOMPUTER>
Content-Type: text/plain; charset="us-ascii"

Fernando,

 

If the date is maintained within a quick screen or updated in a QTP
prcoedure, it is probably a powerhouse null which is not a good thing in
Oracle :-(
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