CREATE TABLE table_201_39 (id DECIMAL, "no" DECIMAL, "title" TEXT, "directed by" TEXT, "released" DECIMAL)

which person has directed most of the titles ?
SELECT "directed by" FROM table_201_39 GROUP BY "directed by" ORDER BY COUNT("title") DESC LIMIT 1
SELECT "directed by" FROM "table_201_39" GROUP BY "directed by" ORDER BY COUNT("title") DESC NULLS LAST LIMIT 1