user: Question: How many different counts of the Raiders first downs are there for the game number 9?
Columns: ['Game', 'Date', 'Opponent', 'Result', 'Raiders points', 'Opponents', 'Raiders first downs', 'Record', 'Attendance']
Types: ['real', 'text', 'text', 'text', 'real', 'real', 'real', 'text', 'real']
Sample row: [1.0, 'Sept. 22', 'at Miami Dolphins', 'Win', 31.0, 21.0, 17.0, '1–0', 78744.0]
SQL:

assistant: SELECT COUNT("Raiders first downs") FROM "Table" WHERE "Game" = 9.0;