Below is the list of tables from the database along with their columns and datatype. Need to generate an accurate SQL query for the question.
Only use the columns present in the respective table. Only use the columns which are required to generate the SQL query. Only use table joins if required and not otherwise.

### Tables ###
TABLE: CREATE TABLE customer_contact_channels ( channel_code VARCHAR, customer_id VARCHAR )

### Question ###
List all the contact channel codes that were used less than 5 times.

### Accurate SQL ###

SELECT channel_code FROM customer_contact_channels GROUP BY channel_code HAVING COUNT(customer_id) < 5