Show all customer ids and the number of accounts for each customer.
SELECT customer_id ,  count(*) FROM Accounts GROUP BY customer_id
SELECT customer_id ,  count(*) FROM Accounts GROUP BY customer_id
[{'customer_id': 2, 'count(*)': 1}, {'customer_id': 4, 'count(*)': 3}, {'customer_id': 6, 'count(*)': 1}, {'customer_id': 8, 'count(*)': 1}, {'customer_id': 9, 'count(*)': 4}, {'customer_id': 10, 'count(*)': 1}, {'customer_id': 12, 'count(*)': 2}, {'customer_id': 13, 'count(*)': 1}, {'customer_id': 14, 'count(*)': 1}]