CREATE TABLE reviewer (rid NUMBER, name CLOB)
CREATE TABLE movie (mid NUMBER, title CLOB, year NUMBER, director CLOB)
CREATE TABLE rating (rid NUMBER, mid NUMBER, stars NUMBER, ratingdate TIME)

Find the title and score of the movie with the lowest rating among all movies directed by each director.
SELECT T2.title, T1.stars, T2.director, MIN(T1.stars) FROM rating AS T1 JOIN movie AS T2 ON T1.mid = T2.mid GROUP BY T2.director
SELECT "T2"."title", "T1"."stars", "T2"."director", MIN("T1"."stars") FROM "rating" "T1" JOIN "movie" "T2" ON "T1"."mid" = "T2"."mid" GROUP BY "T2"."director"