How many matches did Team 10 play in 2012?
Team 10 refers to Team_1 = 10 OR Team_2 = 10; in 2012 refers to SUBSTR(Match_Date, 1, 4) = '2012'
SELECT SUM(CASE WHEN Team_1 = 10 OR Team_2 = 10 THEN 1 ELSE 0 END) FROM `Match` WHERE SUBSTR(Match_Date, 1, 4) = '2012'