What is total number of show times per dat for each cinema?
create table schedule (show_times_per_day integer, cinema_id varchar, PRIMARY KEY (show_times_per_day)); create table cinema (name varchar, cinema_id varchar, PRIMARY KEY (name))
select t2.name, sum(t1.show_times_per_day) from schedule as t1 join cinema as t2 on t1.cinema_id = t2.cinema_id group by t1.cinema_id