Re: Proposal: 6NF
From: J M Davitt <jdavitt_at_aeneas.net>
Date: Tue, 03 Oct 2006 00:19:14 GMT
Message-ID: <60iUg.3585$Cq3.515_at_tornado.ohiordc.rr.com>
>
>
> I don't agree. Judicious use of NULL can improve performance, response
> time, and concurrency.
>
>
Received on Tue Oct 03 2006 - 02:19:14 CEST
Date: Tue, 03 Oct 2006 00:19:14 GMT
Message-ID: <60iUg.3585$Cq3.515_at_tornado.ohiordc.rr.com>
Brian Selzer wrote:
> "Cimode" <cimode_at_hotmail.com> wrote in message
> news:1159797534.237592.159150_at_e3g2000cwe.googlegroups.com...
>
>>Brian Selzer wrote: >> >>>"Roy Hann" <specially_at_processed.almost.meat> wrote in message >>>news:P-Sdnd58Trp7GYLYnZ2dnUVZ8tGdnZ2d_at_pipex.net... >>> >>>>"David Portas" <REMOVE_BEFORE_REPLYING_dportas_at_acm.org> wrote in >>>>message >>>>news:1159692483.421785.264660_at_c28g2000cwb.googlegroups.com... >>>> >>>>>Brian Selzer wrote: >>>>> >>>>>>The argument JOG made focused only on recording information, not >>>>>>retrieving >>>>>>it. Why would anyone abandon a sound mechanism that can >>>>>>significantly >>>>>>reduce the computing capacity required to answer a query? >>>>> >>>>>Because your argument is merely an assumption based on what some >>>>>systems of today are capable of. >>>> >>>>It's worse. His entire position is based on not knowing even what some >>>>of >>>>today's products are already capable of. For example, he seems unaware >>>>of >>>>the role of the optimizer. >>>> >>> >>>I understand fully the role of the optimizer. That's one of my points. >>>If >>>you arbitrarily split a table with a nullable column, then you're robbing >>>the optimizer of possible execution plans. It may make sense to split a >>>table, for example, removing non-key columns that are seldom used in >>>queries >>>into another table in order to boost the performance of all other >>>queries. >>>The point I'm trying to make is that the decision should not be >>>arbitrary. >> >>Consequences of NULL uses goes far above he simple problem of >>execution. It hinders performance at all levels (response time, >>concurrency) and introduces a very strong part of subjectivity in >>interpretation of data presented to users. >>
>
>
> I don't agree. Judicious use of NULL can improve performance, response
> time, and concurrency.
A wrong answer isn't always better because it cost less.
In addition, when used correctly, no subjectivity is
> introduced. For every database schema with NULLable attributes, there is
> always an equivalent schema without.
Well, being the god* you seem to be, I won't doubt that solely because you said so.
- Genius of Design
Any subjectivity would therefore be
> independent of the database schema. On the other hand, arbitrary or
> incorrect use of NULL can cause all of the problems you describe.
>
>
>>>>Roy. >>>> >>
>
>
Received on Tue Oct 03 2006 - 02:19:14 CEST