Jump to content

Complex discount


MA06

Recommended Posts

Hi Guys,

I think this is a complex discount. I have 2 tables in mysql say product1 and product2, with the following characteristics:

[b]product1 table[/b]
p1id......price
1............20
2............30
3............40


[b]product2 table[/b]
p2id.......price........p1id
101.........10............1
102.........20............1
103.........70............1
201.........80............2
202.........6..............2
203.........4..............2
301.........10............3
302.........40............3
303.........30............3

where p1id is a foreign key in product2 table.

[b]Problem[/b]

[b]1)[/b] I have a calculate price function in php, what i want to do is if a person purchases any 2 items from product2 table with the same p1id key e.g. 101 + 102 or 101 +103 not 101 + 201, reduce the price of each of the 2 items by 10%.

[b]2)[/b] Also if they purchase 3 items with the same p1id then reduce the price of each of the 3 items by 15%.

Here is the calculate function i have, WHERE $IDS is a variable with the id of the purchased item. Th code just calculates the prices at the moment:
[code]
function calculate_price($cart)
{
  // sum total price for all items in shopping cart
  $price = 0.0;
  if(is_array($cart))
  {
    $conn = db_connect();
    foreach($cart as $IDS => $qty)
    {  
      $query = "select Price from Product1 where p1id='$IDS' union select Price from Product2 where p2id='$IDS'";

      $result = mysql_query($query);
      if ($result)
      {
        $item_price = mysql_result($result, 0, 'price');
        $price +=$item_price*$qty;
      }
    }
  }
  return $price;
}
[/code]

I am not sure how to apply these 2 discounts to the code, any help would be very much appreciated.

Thanks in advance,

MA.
Link to comment
Share on other sites

If you have MySql 4.1+ you can use a subquery instead of the temporary table but this will work for all versions
[code]
$cart = array (
        101 => 2,
        102 => 1,
        201 => 1,
        202 => 1,
        203 => 1,
        302 => 2
);

$prodList = join(',', array_keys($cart));
$sql = "CREATE TEMPORARY TABLE tmp
        SELECT p1id, COUNT(*) as itemcount FROM product2
        WHERE p2id IN ($prodList)
        GROUP BY p1id";
mysql_query ($sql) or die (mysql_error());

$sql = "SELECT p.p2id, p.price, t.itemcount
        FROM product2 p INNER JOIN tmp t
        ON p.p1id = t.p1id
        WHERE p2id IN ($prodList)
";
$res = mysql_query($sql) or die (mysql_error());
while (list($id, $price, $n) = mysql_fetch_row($res)) {
       switch ($n) {
           case 2: $disc = 0.9; break;
           case 3: $disc = 0.85; break;
           default: $disc = 1; break;
       }
       $discounted = $price*$disc;
       echo "$id, $n, $price, $discounted<br>";
}[/code]
Link to comment
Share on other sites

This thread is more than a year old. Please don't revive it unless you have something important to add.

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Restore formatting

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.