user: Question: What is the smallest gold value that has a total over 15 and bronze values under 31?
Columns: ['Rank', 'Nation', 'Gold', 'Silver', 'Bronze', 'Total']
Types: ['text', 'text', 'real', 'real', 'real', 'real']
Sample row: ['1', 'Japan', 9.0, 2.0, 4.0, 15.0]
SQL:

assistant: SELECT MIN("Gold") FROM "Table" WHERE "Total" > 15.0 AND "Bronze" < 31.0;