CREATE TABLE table_204_312 (id NUMBER, "stage" CLOB, "date" CLOB, "route" CLOB, "terrain" CLOB, "length" CLOB, "winner" CLOB)

which stage was longer , 3 or 8 ?
SELECT "stage" FROM table_204_312 WHERE "stage" IN ('3', '8') ORDER BY "length" DESC LIMIT 1
SELECT "stage" FROM "table_204_312" WHERE "stage" IN ('3', '8') ORDER BY "length" DESC FETCH FIRST 1 ROWS ONLY