Re: Demo: Modelling Cost of Travel Paths Between Towns

On 13 Nov 2004 21:37:38 -0800, Neo wrote:

>> > Storing [at logical level] any thing (ie PA) twice is redundant.
>>
>> A computer represents PA as a string of bits - either 16 or 32 bits on
>> most modern computers....
>
>To repeat from OT "A Normalization Question", which you were a
>significant contributor,

Hi Neo,

I posted a total of 8 messages in that 341 message thread. Only 2 of them were on topic, the remaining six were about you as of yet still unpaid debt of $1,000. (Yeah, I know "please show Neo ..." blah blah).

> how the logical layer of a data model is
>implemented at the hardware level is irrelevant.

Yes, Neo, I know that. I've known it all along, but I've found it very hard to convince you.

Are you now finally prepraed to agree that the two FACTS 1. Neo still owes Hugo $1,000.
2. Neo will probably never pay.
contain no redundancy at all, even though two sets of 24 bits (representing the letter combinations "Neo" and "ill") are part of each of these strings.

>> > On way to prove redundancy is to change the second PA and see if data
>> > is corrupted (without triggers/code to synchronize them).
>>
>> ...changing the second PA would in fact even be required.
>
>Thus proving the second PA is redundant.

You may wish to reread what you wrote: First, you claim that redundancy is proven if a change to the second PA corrupts data; I show that a change of the second PA does NOT corrupt data and you claim that this proves redundancy.

>> > Also, if a property is
>> > added to PA, will you add it the first PA, second PA, or both?
>>
>> You are -once again- showing your total lack of comprehension of
>> normalization. If a propert is added to PA, it should be added in a
>> seperate table.
>
>Yes, a separate table for states is the correct way to avoid redundant
>PA's (even if PA doesn't have any properties).

Wrong. In the relational model, a seperate table for states that have no properties would in fact be redundant - unless the application calls for a full listing of states, even if currently no town is located in that state.

> Alan didn't provide
>such a schema thus he has redundant PA's. Also note, the notion of
>having to add a table in order to accomodate properties is a
>characteristic of RM and not necessarily that of other data models
>such TM/XDb2.

I'm fully aware of the characteritics of RM, thank you very much.

Best, Hugo

-- 

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