CREATE TABLE table_204_630 (id DECIMAL, "no" DECIMAL, "date" TEXT, "race" TEXT, "track" TEXT, "winner" TEXT, "reports" TEXT)

which is longer the carolina or kentucky race ?
SELECT "race" FROM table_204_630 WHERE "race" IN ('carolina 500', 'kentucky') ORDER BY "no" DESC LIMIT 1
SELECT "race" FROM "table_204_630" WHERE "race" IN ('carolina 500', 'kentucky') ORDER BY "no" DESC NULLS LAST LIMIT 1