user: Question: Which Date has a Record of 8:39.49?
Columns: ['Event', 'Record', 'Nation', 'Date', 'Venue']
Types: ['text', 'text', 'text', 'text', 'text']
Sample row: ['60 m', '7.00', 'Netherlands', '23 February 1986', '1986 Madrid']
SQL:

assistant: SELECT "Date" FROM "Table" WHERE "Record" = '8:39.49';