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

What is the average rating star for each reviewer?
SELECT T2.name, AVG(T1.stars) FROM rating AS T1 JOIN reviewer AS T2 ON T1.rid = T2.rid GROUP BY T2.name
SELECT "T2"."name", AVG("T1"."stars") FROM "rating" "T1" JOIN "reviewer" "T2" ON "T1"."rid" = "T2"."rid" GROUP BY "T2"."name"