CREATE TABLE Accounts (account_id INT, customer_id INT, account_name VARCHAR, other_account_details VARCHAR)
CREATE TABLE Customers_Cards (card_id INT, customer_id INT, card_type_code VARCHAR, card_number VARCHAR, date_valid_from DATETIME, date_valid_to DATETIME, other_card_details VARCHAR)
CREATE TABLE Financial_Transactions (transaction_id INT, previous_transaction_id INT, account_id INT, card_id INT, transaction_type VARCHAR, transaction_date DATETIME, transaction_amount DOUBLE, transaction_comment VARCHAR, other_transaction_details VARCHAR)
CREATE TABLE Customers (customer_id INT, customer_first_name VARCHAR, customer_last_name VARCHAR, customer_address VARCHAR, customer_phone VARCHAR, customer_email VARCHAR, other_customer_details VARCHAR)

Visualize a scatter chart on how many accounts are there for each customer id?
SELECT customer_id, COUNT(*) FROM Accounts GROUP BY customer_id
SELECT "customer_id", COUNT(*) FROM "Accounts" GROUP BY "customer_id"