Customer Who Visited but Did Not Make Any Transactions.sql

# Write your MySQL query statement below
# Write your MySQL query statement below

SELECT v.customer_id, COUNT(v.visit_id) AS count_no_trans 
from Visits v 
LEFT JOIN Transactions t 
ON v.visit_id = t.visit_id  
WHERE t.transaction_id IS NULL 
GROUP BY v.customer_id; 


#UPDATE DEC 1ST : we take the t.amount as null
/*SELECT v.customer_id, COUNT(v.visit_id) AS count_no_trans 
from Visits v 
LEFT JOIN Transactions t 
ON v.visit_id = t.visit_id  
WHERE t.amount IS NULL 
GROUP BY v.customer_id; 
*/