CREATE TABLE Customers (customer_id VARCHAR, customer_first_name VARCHAR, customer_last_name VARCHAR)
CREATE TABLE Customers_cards (customer_id VARCHAR, card_type_code VARCHAR)

How many credit cards does customer Blanche Huels have?
SELECT COUNT(*) FROM Customers_cards AS T1 JOIN Customers AS T2 ON T1.customer_id = T2.customer_id WHERE T2.customer_first_name = "Blanche" AND T2.customer_last_name = "Huels" AND T1.card_type_code = "Credit"
SELECT COUNT(*) FROM "Customers_cards" AS "T1" JOIN "Customers" AS "T2" ON "Blanche" = "T2"."customer_first_name" AND "Huels" = "T2"."customer_last_name" AND "T1"."customer_id" = "T2"."customer_id" WHERE "Credit" = "T1"."card_type_code"