Subject | Re: [ib-support] join-sort question |
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Author | Helen Borrie |
Post date | 2001-07-03T12:14:40Z |
At 12:27 PM 03-07-01 +0200, you wrote:
[problem snipped]
and solved by Svein...
Why is the relationship not formed with the patient id alone?
Regards,
Helen
All for Open and Open for All
InterBase Developer Initiative ยท http://www.interbase2000.org
_______________________________________________________
[problem snipped]
and solved by Svein...
>select p.*, s.* from patients p left outer join patientstatus sbut...I observe the potential for chaos here, with this composite key in a 1:1 relationship. What happens if the admitting staff enter patient 101 as "Mary Ann Smith" into Patients and the clinical staff enter patient 101 as "Maryann Smith" into PatientStatus? With this key structure, the two will never match up. (Two RDBMS thunderclouds: non-atomic keys and redundancy!)
>on ((p.id=s.id) and (p.name=s.name)) order by patients.name
>
>and you should be fine.
Why is the relationship not formed with the patient id alone?
Regards,
Helen
All for Open and Open for All
InterBase Developer Initiative ยท http://www.interbase2000.org
_______________________________________________________