CREATE TABLE table_16720 ("Rnd" FLOAT, "Race" CLOB, "Date" CLOB, "Location" CLOB, "Pole Position" CLOB, "Fastest Lap" CLOB, "Race Winner" CLOB, "Constructor" CLOB, "Report" CLOB)

What race had Nelson Piquet on the pole and was in N rburgring?
SELECT "Race" FROM table_16720 WHERE "Pole Position" = 'Nelson Piquet' AND "Location" = 'Nürburgring'
SELECT "Race" FROM "table_16720" WHERE "Location" = 'Nürburgring' AND "Pole Position" = 'Nelson Piquet'