PHP和Mysql - 嵌套循环

Question

I have 2 tables - products and productimages. product has unique id and title. productimages has productid and imageurl. these are examples of my tables:

products:

|id|title    |
_____________
|1 |Laptop   |
|2 |Speakers |

productimages:

|productid|imageurl|
___________________
|    1    |lap1.png|
|    1    |lap2.png|
|    1    |lap3.png|
|    2    |spe1.png|

Right now I have a nested loop in PHP. loop through all rows of -> select * from products and for every product inside the loop -> select * from productimages where productid = id which is basically another loop inside the first loop.

and then I take all productimages into array and decode to JSON [title,photos].

Now imagine you have 2 million rows in productimages, the query times are too high, is there any way to make it more efficient?

$query = "SELECT * FROM products ORDER BY id LIMIT 10;
$result = mysqli_query($con,$query);

if(mysqli_num_rows($result)>0)
{
    $response = array();
    while($row = mysqli_fetch_assoc($result)) {
        $photos = array();
        $id = $row["id"];
        $title = $row["title"];         

        $queryp = "select imageurl from productimages where productid= '".$id."';";
        $resultp = mysqli_query($con,$queryp);

        if(mysqli_num_rows($resultp)>0)
        {
            while($row2 = mysqli_fetch_assoc($resultp)) {
                $photourl = $row2["imageurl"];
                array_push($photos,$photourl);
            }
        }
     }
  }

Answer 1

Some betterment for you could be:

1) Don't use select *. Use column names instead. e.g. select products.id, products.title, productimages.imageurl

2) Use JOIN instead of nested loop

So, you can try querying data like:

select products.id, products.title, productimages.imageurl
from products
join productimages on products.id = productimages.productid
ORDER BY products.id LIMIT 10