Re: Distributed foreign keys (was Re: Category Types)

Paul Vernon wrote:
> "Alexey Kirich" <kirich_a_at_softline.kiev.ua> wrote in message
> news:3ef01f21$1_at_ns...
> [snip]
>

>>This approach can be made with hope, that in the future RDBMSs will support
>>OR like foreign constraints.

I've read it, and my personal opinion is that it's totally flawed.

Here's the "recomposition" query:

WITH (EXTEND JOB_UNK ADD ‘Job unknown’ AS Job_info) AS T1,

(EXTEND UNEMPLOYED ADD ‘Unemployed’ AS Job_info) AS T2,
(DOES_JOB RENAME (Job AS Job_info)) AS T3,
(EXTEND SALARY_UNK ADD ‘Salary unknown’ AS Sal_info) AS T4,
(EXTEND UNSALARIED ADD ‘Unsalaried’ AS Sal_info) AS T5,
(EXTEND EARNS ADD CHAR(Salary) AS Sal_info) AS T6,
(T6 { ALL BUT Salary }) AS T7,
(UNION ( T1, T2, T3 )) AS T8,
(UNION ( T4, T5, T7 )) AS T9,
(JOIN ( CALLED, T8, T9 )) AS PERS_INFO :

The query above is not mathematical elegance, it is mathematical clumsiness.

What was there to discuss about it ?

Cheers,
Costin Received on Wed Jun 25 2003 - 02:14:44 CEST