for which user id rating is high | did you mean for which user id is the rating highest? | ok, find user id who gives the rating 10
SELECT T1.u_id FROM useracct AS T1 JOIN review AS T2 ON T1.u_id  =  T2.u_id WHERE T2.rating  =  10
user id who gives the rating 10 refers to filtering users with a rating of 10; JOIN operation is used to link user account information with their review ratings;