How many problems does the product with the most problems have? List the number of the problems and product name.
create table problems (product_id varchar, PRIMARY KEY (product_id)); create table product (product_name varchar, product_id varchar, PRIMARY KEY (product_name))
select count(*), t1.product_name from product as t1 join problems as t2 on t1.product_id = t2.product_id group by t1.product_name order by count(*) desc limit 1