Question

Got table for main product listing:

| id | name | content |
  1    bla     .....
  2    ble     .....
  3    blo     .....
  4    blu     .....

And table for scoring products:

| id | productid | score |
  1        4         4
  2        2         3
  3        4         1
  4        3         1
  3        1         1
  3        2         2

Started to write code for product listing, with paginate class > smarty

$stmt = $mysqli->prepare("SELECT id,name,content FROM products LIMIT ?,?"))
$stmt->bind_param('ii', SmartyPaginate::getCurrentIndex('id'), SmartyPaginate::getLimit('id'));
$stmt->bind_result($id, $name, $content);
$stmt->execute();

$count = '0';

while ($stmt->fetch())
 {
$array['id'][]          = $id;
$array['name'][]        = $name;
$array['content'][] = $content;
$count++;
  }

rest code...

It works superb for product listings, but now i need to order products accordinally to average got from score table.

I have seen many examples for rankings but still can’t build anything that would work.

Thanks in advance
Camel

Answer 1

select * from product left join ( select avg(score) avgscore, productid from scoring group by productid ) s on s.productid = product.productid order by avgscore limit 0,10

one way to optimize the query store the avg in the product table and update it occasionally.