user: Question: What is the smallest number of silvers associated with bronzes under 20, totals of 1, golds of 0, and in water polo?
Columns: ['Sport', 'Gold', 'Silver', 'Bronze', 'Total']
Types: ['text', 'real', 'real', 'real', 'real']
Sample row: ['Athletics', 32.0, 42.0, 49.0, 125.0]
SQL:

assistant: SELECT MIN("Silver") FROM "Table" WHERE "Bronze" < 20.0 AND "Total" = 1.0 AND "Sport" = 'water polo' AND "Gold" < 0.0;