CREATE TABLE table_203_538 (id DECIMAL, "flight" TEXT, "date" TEXT, "payload nickname" TEXT, "payload" TEXT, "orbit" TEXT, "result" TEXT)

what h ii flight took place last ?
SELECT "flight" FROM table_203_538 ORDER BY "date" DESC LIMIT 1
SELECT "flight" FROM "table_203_538" ORDER BY "date" DESC NULLS LAST LIMIT 1