user: Question: What were the fewest amount of guns possessed by a Frigate that served in 1815?
Columns: ['Ship', 'Guns', 'Class', 'Captain', 'Rank', 'Year']
Types: ['text', 'real', 'text', 'text', 'text', 'text']
Sample row: ['HMS Hyperion', 74.0, 'Third-rate ship of the line', 'Richard Bolitho', 'Midshipman', '1794']
SQL:

assistant: SELECT MIN("Guns") FROM "Table" WHERE "Class" = 'Frigate' AND "Year" = '1815';