Re: boolean datatype ... wtf?

On Wed, 6 Oct 2010 02:44:08 -0700 (PDT), Erwin wrote:

>On 5 okt, 00:53, Hugo Kornelis <h..._at_perFact.REMOVETHIS.info.INVALID>
>wrote:
>> On Sat, 02 Oct 2010 10:42:50 -0300, Bob Badour wrote:
>>
>> >What makes either of those choices logical?
>>
>> Hi Bob,
>>
>> My first observation is that these three possibilities do not come from
>> a single domain. Male and female are values from the domain of genders;
>> unknown is not. So it would be wrong to define a domain with three
>> values to represent the three possibilities.
>>
>> But if unknown is not in the same domain as male and female, then what
>> is it?
>
>From domain boolean ?

Eh? I guess I don't understand what you mean. Why bring up the domain boolean at this point in my reasoning? Either I misunderstand what you try to say, or you misunderstood what I tried to say.

>Even Brian acknowledged that NULLs are (what he called) "indicators",
>or iow, boolean flags, or yet iow, 2VL truth values. They say whether
>data is really present yes or no. That sounds very boolean to me.

Probably. But I guess Brian kind of lost me when he wrote that a single nullable column has to be replaced by not one but two seperate tables in a null-less design.

>Now guess what. Would the fact that I think it is better to eliminate
>booleans from a logical database design by vertical decomposition,
>have anything to do with the fact that I also think it is better to
>eliminate nulls from a logical database design by vertical
>decomposition ?

I think I accomodated for the "NULL haters" by also including the alternative design with an extra table and no nullable columns.

>> That's the logic of the first choice.
>
>I think you missed the point about 'logic'.

Well, then I'm sure you can explain exactly when and where I missed the point about logic, how you think I went wrong and what I should have written.
For if you make only this remark without further arguments, it is just an unfounded ad-hom attack that adds nothing to the discussion.

Best, Hugo Received on Wed Oct 06 2010 - 13:50:23 CEST