Schema: CREATE TABLE customers (customer_name VARCHAR, customer_id VARCHAR); CREATE TABLE customer_contact_channels (active_from_date VARCHAR, customer_id VARCHAR, channel_code VARCHAR)
Question: Find the name and active date of the customer that use email as the contact channel.
SQL: SELECT t1.customer_name, t2.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'