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31 March 2002 14:24bloody SQL assignment is killing me.
"List all data from the Person table who are niether staff nor patients."
fucked if I know.
Why does
WHERE person.person_id = staff.person_id
AND person.person_id = admission.patient_id
work and
WHERE person.person_id <> staff.person_id
AND person.person_id <> admission.patient_id
not?
"List all data from the Person table who are niether staff nor patients."
fucked if I know.
Why does
WHERE person.person_id = staff.person_id
AND person.person_id = admission.patient_id
work and
WHERE person.person_id <> staff.person_id
AND person.person_id <> admission.patient_id
not?
