user: Question: Who was the opponent that played on May 12?
Columns: ['Date', 'Opponent', 'Score', 'Loss', 'Attendance', 'Record']
Types: ['text', 'text', 'text', 'text', 'text', 'text']
Sample row: ['May 2', 'Athletics', '8 - 5', 'Ward (1-4)', '23,439', '9-17']
SQL:

assistant: SELECT "Opponent" FROM "Table" WHERE "Date" = 'May 12';