CREATE TABLE useracct (u_id DECIMAL, name TEXT)
CREATE TABLE item (i_id DECIMAL, title TEXT)
CREATE TABLE review (a_id DECIMAL, u_id DECIMAL, i_id DECIMAL, rating DECIMAL, rank DECIMAL)
CREATE TABLE trust (source_u_id DECIMAL, target_u_id DECIMAL, trust DECIMAL)

Find the average and maximum rating of all reviews.
SELECT AVG(rating), MAX(rating) FROM review
SELECT AVG("rating"), MAX("rating") FROM "review"