CREATE TABLE Customers_cards (customer_id VARCHAR)

What is the customer id with most number of cards, and how many does he have?
SELECT customer_id, COUNT(*) FROM Customers_cards GROUP BY customer_id ORDER BY COUNT(*) DESC LIMIT 1
SELECT "customer_id", COUNT(*) FROM "Customers_cards" GROUP BY "customer_id" ORDER BY COUNT(*) DESC NULLS LAST LIMIT 1