Below is the list of tables from the database along with their columns and datatype. Need to generate an accurate SQL query for the question.
Only use the columns present in the respective table. Only use the columns which are required to generate the SQL query. Only use table joins if required and not otherwise.

### Tables ###
TABLE: CREATE TABLE patient (SSN VARCHAR)
TABLE: CREATE TABLE prescribes (patient VARCHAR, physician VARCHAR)
TABLE: CREATE TABLE physician (employeeid VARCHAR, name VARCHAR)

### Question ###
How many patients' prescriptions are made by physician John Dorian?

### Accurate SQL ###

SELECT COUNT(T1.SSN) FROM patient AS T1 JOIN prescribes AS T2 ON T1.SSN = T2.patient JOIN physician AS T3 ON T2.physician = T3.employeeid WHERE T3.name = "John Dorian"