Show the id and details for the investors who have the top 3 number of transactions.
create table transactions (investor_id varchar, PRIMARY KEY (investor_id)); create table investors (investor_details varchar, investor_id varchar, PRIMARY KEY (investor_details))
select t2.investor_id, t1.investor_details from investors as t1 join transactions as t2 on t1.investor_id = t2.investor_id group by t2.investor_id order by count(*) desc limit 3