Get your hands dirty with SQL.
You will use only SQL queries for this.
Using the same tennis data, find the number of matches played by each player in each tournament (remember that a player can be present as both player1 or player2)
Who has played the most matches total in all of US Open, AUST Open, French Open? Answer this both for men and women.
Who has the highest first serve percentage? (Just the maximum value in a single match)
What are the unforced error percentages of the top three players with the most wins? (unforced error percentage is % of points lost due to unforced errors. In a match, you have fields for number of points won by each player, and number of unforced errors for each field).
SUM(double_faults)function sums the contents of an entire column. if, for each row, you want to add the field values from two columns, you can just do
SELECT name, double_faults + unforced_errors