Find the driver id and number of races of all drivers who have at most participated in 30 races?
return drivers ;return number of  races of #1 ;return #1 where  #2 is  at most 30 ;return driver id of  #3 ;return number of races of  #3 ;return #4 ,   #5
['select', 'project', 'comparative', 'project', 'project', 'union']