What is the id, name and nationality of the architect who built most mills?
create table architect (id varchar, name varchar, nationality varchar, PRIMARY KEY (id)); create table mill (architect_id varchar, PRIMARY KEY (architect_id))
select t1.id, t1.name, t1.nationality from architect as t1 join mill as t2 on t1.id = t2.architect_id group by t1.id order by count(*) desc limit 1