user: Question: Which Purpose has a Name of Oak?
Columns: ['Name', 'Location', 'Elevation + Height', 'Delivery', 'Purpose', 'Yield']
Types: ['text', 'text', 'text', 'text', 'text', 'text']
Sample row: ['Yucca', 'Pacific Ocean', '0 + kilometres (mi)', 'Balloon', 'Weapon effect', '1.7 kt']
SQL:

assistant: SELECT "Purpose" FROM "Table" WHERE "Name" = 'Oak';