CREATE TABLE customers_cards (card_id DECIMAL, customer_id DECIMAL, card_type_code TEXT, card_number TEXT, date_valid_from TIME, date_valid_to TIME, other_card_details TEXT)
CREATE TABLE accounts (account_id DECIMAL, customer_id DECIMAL, account_name TEXT, other_account_details TEXT)
CREATE TABLE customers (customer_id DECIMAL, customer_first_name TEXT, customer_last_name TEXT, customer_address TEXT, customer_phone TEXT, customer_email TEXT, other_customer_details TEXT)
CREATE TABLE financial_transactions (transaction_id DECIMAL, previous_transaction_id DECIMAL, account_id DECIMAL, card_id DECIMAL, transaction_type TEXT, transaction_date TIME, transaction_amount DECIMAL, transaction_comment TEXT, other_transaction_details TEXT)

Show the card type codes and the number of transactions.
SELECT T2.card_type_code, COUNT(*) FROM financial_transactions AS T1 JOIN customers_cards AS T2 ON T1.card_id = T2.card_id GROUP BY T2.card_type_code
SELECT "T2"."card_type_code", COUNT(*) FROM "financial_transactions" AS "T1" JOIN "customers_cards" AS "T2" ON "T1"."card_id" = "T2"."card_id" GROUP BY "T2"."card_type_code"