instruction: Find the number of customers that use email as the contact channel and group by customer name and bin active date by weekday in a stacked bar chart.
response: SELECT active_from_date, COUNT(active_from_date) FROM Customers AS t1 JOIN Customer_Contact_Channels AS t2 ON t1.customer_id = t2.customer_id WHERE t2.channel_code = 'Email' GROUP BY customer_name