user: Question: What date was a Brig type ship located in SW Approaches?
Columns: ['Date', 'Ship Name', 'Tonnage', 'Ship Type', 'Location', 'Disposition of Ship']
Types: ['text', 'text', 'text', 'text', 'text', 'text']
Sample row: ['30 August 1814', 'Lettice', 't', 'Brig', 'English Channel', 'Captured']
SQL:

assistant: SELECT "Date" FROM "Table" WHERE "Ship Type" = 'Brig' AND "Location" = 'SW Approaches';