How many accounts does each customer have? List the number and customer id.
SELECT count(*) ,  customer_id FROM Accounts GROUP BY customer_id
SELECT count(*) ,  customer_id FROM Accounts GROUP BY customer_id
[{'count(*)': 1, 'customer_id': 3}, {'count(*)': 1, 'customer_id': 6}, {'count(*)': 4, 'customer_id': 8}, {'count(*)': 1, 'customer_id': 9}, {'count(*)': 1, 'customer_id': 12}, {'count(*)': 4, 'customer_id': 13}, {'count(*)': 3, 'customer_id': 15}]