user: Question: What is the diff for a club that has a value of 662 for points for?
Columns: ['Club', 'Total points', 'Bonus points', 'Match points', 'Games', 'Drawn', 'Lost', 'Points for', 'Points against', 'Diff']
Types: ['text', 'text', 'text', 'text', 'text', 'text', 'text', 'text', 'text', 'text']
Sample row: ['Club', 'Total points', 'Bonus points', 'Match points', 'Games', 'Drawn', 'Lost', 'Points for', 'Points against', 'Diff']
SQL:

assistant: SELECT "Diff" FROM "Table" WHERE "Points for" = '662';