Table: nhl_game_stats_17
Columns: date
visitor
score
home
decision
attendance
record

Question: How many attended on march 1?
SQL: SELECT AVG("attendance") FROM nhl_game_stats_17 WHERE "date" = 'march 1'

Question: Who was the visitor on march 21?
SQL: SELECT "visitor" FROM nhl_game_stats_17 WHERE "date" = 'march 21'