How many customers does Steve Johnson support?
SELECT count(*) FROM employees AS T1 JOIN customers AS T2 ON T2.support_rep_id = T1.id WHERE T1.first_name = "Steve" AND T1.last_name = "Johnson";
SELECT count(*) FROM employees AS T1 JOIN customers AS T2 ON T2.support_rep_id = T1.id WHERE T1.first_name = "Steve" AND T1.last_name = "Johnson";
[{'count(*)': 18}]