user: Question: On the date October 21, 2007, what is the No.?
Columns: ['Outcome', 'No.', 'Date', 'Championship', 'Surface', 'Opponent in the final', 'Score in the final']
Types: ['text', 'text', 'text', 'text', 'text', 'text', 'text']
Sample row: ['Winner', '46.', 'January 28, 2007', 'Australian Open, Melbourne, Australia (3)', 'Hard', 'Fernando González', '7–6 (7–2) , 6–4, 6–4']
SQL:

assistant: SELECT "No." FROM "Table" WHERE "Date" = 'October 21, 2007';