php - How can i join this 2 MySQL queries together -

I have a query that pulls in some products, there are several products and the list will increase

  TimedStamp DESC by ORDER from seed pid, link, made_at products   
 But I also have another table that includes  pid  and  rating  The field is a link to the table of products  pid .  
  SELECT avig (rating) rating group pid   
 How can I query so that it can remove information as below?  
  products.pid, products.link, products.created_at, avg (rating.Rating)    
 
 
 In MySQL, this should give you the desired results;   
  SELECT p.pid, p.link, p.created_at, avg (r.rating) products by LEFT JOIN rating r ON p. Pid = r.pid GROUP BY p.pid;   
.  
 As a side note, MySQL is special because it lets you query incomplete  GROUP BY , so if you want to run it on other databases (or possibly stylish reasons), the query is instead should be there;  
 
 
 
 
 
 
  
 = RPID Group by PPID, P.Link, P.Kerated_Att;