CREATE TABLE table_204_517 (id DECIMAL, "name" TEXT, "date of birth" TEXT, "club" TEXT, "division" TEXT, "appointed" TEXT, "time as manager" TEXT)

who served as manager longer - francis bosschaerts or peter maes ?
SELECT "name" FROM table_204_517 WHERE "name" IN ('francis bosschaerts', 'peter maes') ORDER BY "date of birth" LIMIT 1
SELECT "name" FROM "table_204_517" WHERE "name" IN ('francis bosschaerts', 'peter maes') ORDER BY "date of birth" NULLS FIRST LIMIT 1