Re: My 10 Commandments of Database Administration...

Nuno,

If you don't mind me asking...

What value do you use to imply "this record does not have an end date yet - it is current". Do you insist on an additional attribute? Use a particularly large date? I would have thought that from a design point of view a NULL end date would mean "we have no idea when this record will be end dated" and my main reason in the past for avoiding this related to indexing (rightly, or wrongly - let's not enter that debate right now).

I guess a lot of people have the idea that a record which has started to be effective, but has not ended (and has no planned end date) is best described by leaving end date null since the record has no known end date. I'm genuinely interested to hear your opinion on this because it's a discussion I've entered on more than one occaision?

Regards,

      Mark.

                                                                                                                                       
                      "Nuno Pinto do                                                                                                   
                      Souto"                    To:       <oracle-l_at_freelists.org>                                                     
                      <nsouto_at_bizmail.co        cc:                                                                                    
                      m.au>                     Subject:  Re: My 10 Commandments of Database Administration...                         
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                      oracle-l-bounce_at_fr                                                                                               
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                      23/09/2004 10:40                                                                                                 
                      Please respond to                                                                                                
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Quoting from AUTHOR ryan gaffuri:
> 11. Thou shalt feed me if I have to work late to fix something you
> broke.
>
> I'm a single guy...

Nuno's design corollary #1:

Thou shall not use end_date = NULL to mean "current row" of ANYTHING! NULL has NO MEANING whatsoever: it does NOT mean "current"!

Under penalty of having to cook for Nuno (and I'm a heavy bloke)...

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