Joshua D. Drake wrote:
> Gregory Stark wrote:
>
>> "David Fetter" <david@fetter.org> writes:
>>
>>
>>> CREATE TABLE symptom (
>>> symptom_id SERIAL PRIMARY KEY, /* See above. */
>>> ...
>>> );
>>>
>>> CREATE TABLE patient_presents_with (
>>> patient_id INTEGER NOT NULL REFERENCES patient(patient_id),
>>> symptom_id INTEGER NOT NULL REFERENCES symptom(symptom_id),
>>> UNIQUE(patient_id, symptom_id)
>>> );
>>>
>> I'm just glad I don't have your doctor. I hope mine doesn't think symptoms are
>> all boolean values.
>>
>
> With a unique across (patient_id,symptom_id) you could have a single
> patient with as many unique symptoms as could be listed.
>
>
>
>
I think Greg is suggesting that the table needs to be augmented with,
say, a severity field.
cheers
andrew
