CREATE TABLE table_name_97 (date INT, u_boats_destroyed__pola_ VARCHAR)

What's the highest Date listed that has U-boats destroyed (Pola) of 1?
SELECT MAX(date) FROM table_name_97 WHERE u_boats_destroyed__pola_ = "1"
SELECT MAX("date") FROM "table_name_97" WHERE "1" = "u_boats_destroyed__pola_"