For each user, return the name and the average rating of reviews given by them.
SELECT T1.name ,  avg(T2.rating) FROM useracct AS T1 JOIN review AS T2 ON T1.u_id  =  T2.u_id GROUP BY T2.u_id
SELECT T1.name ,  avg(T2.rating) FROM useracct AS T1 JOIN review AS T2 ON T1.u_id  =  T2.u_id GROUP BY T2.u_id
[{'name': 'Helen', 'avg(T2.rating)': 7.333333333333333}, {'name': 'Mark', 'avg(T2.rating)': 7.0}]