What is the total amount of assists of the NHL player with the most assists in history? Please indicate his/her full name.
NHL refers to lgID = 'NHL'; most assists refers to max(A); full name = nameGiven + lastName; total amount of assists = sum(A(playerID(max(A))))
SELECT SUM(T1.A), T2.firstName, T2.lastName FROM Scoring AS T1 INNER JOIN Master AS T2 ON T1.playerID = T2.playerID WHERE T1.lgID = 'NHL' GROUP BY T2.firstName, T2.lastName ORDER BY SUM(T1.A) DESC LIMIT 1