What are the id and name of the museum visited most times?
create table museum (name varchar, museum_id varchar, PRIMARY KEY (name)); create table visit (museum_id varchar, PRIMARY KEY (museum_id))
select t2.museum_id, t1.name from museum as t1 join visit as t2 on t1.museum_id = t2.museum_id group by t2.museum_id order by count(*) desc limit 1