Table: grand_slam_tennis_players
Columns: col
player
age
australian_open
french_open
wimbledon
us_open

Question: How many players are on this list?
SQL: SELECT MAX("col") FROM grand_slam_tennis_players

Question: Who won the French Open in 1999?
SQL: SELECT "player" FROM grand_slam_tennis_players WHERE "french_open" = 1999

Question: Who won the US Open in 1937?
SQL: SELECT "player" FROM grand_slam_tennis_players WHERE "us_open" = 1937

Question: How many times did Roy Emerson win the Australian Open?
SQL: SELECT COUNT("australian_open") FROM grand_slam_tennis_players WHERE "player" = 'Roy Emerson'

Question: At what age did Roy Emerson complete the Grand Slam?
SQL: SELECT MAX("age") FROM grand_slam_tennis_players WHERE "player" = 'Roy Emerson'