Re: A question for Mr. Celko
From: Jan Hidders <jan.hidders_at_REMOVETHIS.pandora.be>
Date: Sun, 18 Jul 2004 10:11:46 GMT
Message-Id: <pan.2004.07.18.10.12.22.935425_at_REMOVETHIS.pandora.be>
>
> I hypothesize that you can have list-valued-attributes inline (as is
> already often the case with strings) and relation-valued attributes
> implemented as separate relations, and still keep things quite simple.
> I'm still investigating this, though.
Date: Sun, 18 Jul 2004 10:11:46 GMT
Message-Id: <pan.2004.07.18.10.12.22.935425_at_REMOVETHIS.pandora.be>
On Sun, 18 Jul 2004 00:12:27 +0000, Marshall Spight wrote:
> "Jan Hidders" <jan.hidders_at_REMOVETHIS.pandora.be> wrote in message
> news:pan.2004.07.17.23.23.54.257337_at_REMOVETHIS.pandora.be...
>> On Sat, 17 Jul 2004 15:37:00 +0000, Marshall Spight wrote: >> > >> > [...] 1NF doesn't seem to do anything but get in the way of things >> > like relation-valued or list-valued attributes. >> >> Good question. I would argue that it keeps things simple. [...]
>
> I hypothesize that you can have list-valued-attributes inline (as is
> already often the case with strings) and relation-valued attributes
> implemented as separate relations, and still keep things quite simple.
> I'm still investigating this, though.
So what happens for example if the list is really big and I do a join between the list and the relation in the relation-valued attribute. Will your query optimizer recoginize that situation and choose the right join algorithm? Do you know how hard it is to decide whether a certain list operation is actually a natural join?
- Jan Hidders