To filter patients'
IDs by odd numbers, you can of course take a look at the to check the
ID's manually and use the
IN operator in the following manner:
WHERE patient.id IN (1, 3, 5 ... 15)
However, there is also a more concise way to do this. When dividing an odd number by two, the remainder is always 1.
MOD() (modulo) function to find the remainder after division of one number by another. The use of the modulo function in this exercise is as follows:
WHERE MOD(patient.id, 2) = 1
ON physician_id = physician.id
ON patient_id = patient.id
ON treatment_type = treatment.type
WHERE physician.last_name IN ('Core', 'Calderwood')
AND MOD(patient.id, 2) = 1