2 different approaches for this question(one is easy to understand other is quick to process)
EASY TO UNDERSTAND - select name from salesperson where sales_id not in (select sales_id from orders where com_id  in (select com_id from company where name = \
EASY TO UNDERSTAND - select name from salesperson where sales_id not in (select sales_id from orders where com_id  in (select com_id from company where name = \'RED\'));\n\n\nEASIER FOR THE MACHINES TO PROCESS - select name from salesperson where sales_id not in \n(select sales_id  from orders\nleft join company on orders.com_id = company.com_id\nwhere name = \'RED\');
['MySQL']