How many transactions were paid through MasterCard in 2014?
MasterCard refers to CreditCardType = 'MasterCard'; in 2014 refers to TransactionDate > = '2014-01-01' AND TransactionDate < = '2014-12-31';
SELECT COUNT(TransactionID) FROM `transaction` WHERE CreditCardType = 'MasterCard' AND TransactionDate LIKE '2014%'