CREATE TABLE customer_orders (order_id NUMBER, customer_id NUMBER, order_status CLOB, order_date TIME, order_details CLOB)
CREATE TABLE products (product_id NUMBER, product_details CLOB)
CREATE TABLE order_items (order_id NUMBER, product_id NUMBER, order_quantity CLOB)
CREATE TABLE customer_contact_channels (customer_id NUMBER, channel_code CLOB, active_from_date TIME, active_to_date TIME, contact_number CLOB)
CREATE TABLE customers (customer_id NUMBER, payment_method CLOB, customer_name CLOB, date_became_customer TIME, other_customer_details CLOB)
CREATE TABLE addresses (address_id NUMBER, address_content CLOB, city CLOB, zip_postcode CLOB, state_province_county CLOB, country CLOB, other_address_details CLOB)
CREATE TABLE customer_addresses (customer_id NUMBER, address_id NUMBER, date_address_from TIME, address_type CLOB, date_address_to TIME)

Which contact channel codes were used less than 5 times?
SELECT channel_code FROM customer_contact_channels GROUP BY channel_code HAVING COUNT(customer_id) < 5
SELECT "channel_code" FROM "customer_contact_channels" GROUP BY "channel_code" HAVING COUNT("customer_id") < 5