CREATE TABLE category (id INT, business_id VARCHAR, category_name VARCHAR)
CREATE TABLE user (uid INT, user_id VARCHAR, name VARCHAR)
CREATE TABLE business (bid INT, business_id VARCHAR, name VARCHAR, full_address VARCHAR, city VARCHAR, latitude VARCHAR, longitude VARCHAR, review_count BIGINT, is_open TINYINT, rating FLOAT, state VARCHAR)
CREATE TABLE review (rid INT, business_id VARCHAR, user_id VARCHAR, rating FLOAT, text TEXT, year INT, month VARCHAR)
CREATE TABLE neighborhood (id INT, business_id VARCHAR, neighborhood_name VARCHAR)
CREATE TABLE checkin (cid INT, business_id VARCHAR, count INT, day VARCHAR)
CREATE TABLE tip (tip_id INT, business_id VARCHAR, text TEXT, user_id VARCHAR, likes INT, year INT, month VARCHAR)

Find users whose average review rating is below 3
SELECT user.name FROM review, user WHERE user.user_id = review.user_id GROUP BY user.name HAVING AVG(review.rating) < 3
SELECT "user"."name" FROM "review" JOIN "user" ON "review"."user_id" = "user"."user_id" GROUP BY "user"."name" HAVING AVG("review"."rating") < 3