Select query joining two tables PHP

Question

I have put a script together which prints all of the rows from the " sales_list " table but only those with the " users_sales_guild_id " which matches the logged in user. This works fine.

What I am trying to do is print all of the rows but retrieve the matching sales_id from the "accessories_orders" table, and put the "accessories_orders_total" and shipped status with the query, so the query below should look like this in the browser if the person logging in has a "user_sales_guild_id" value of "1234" .

+--------+---------------+-------------------+----------+
| Model  | Customer Name | Accessories Total | Status   | 
+--------+---------------+-------------------+----------+
| Nissan | Malcom Smith  |                   | Add      |
| Ford   | Jane Smith    | 200.00            | Pending  | 
+------------------------+-------------------+----------+

So if there is a matching row in the "accessories_orders" table, then it will print the "shipped" and "accessories_orders_total" data. If there is no matching row for this, then it will display an "Add" link which leads to the add_accessories_sales.php.

I'm getting an error message "Undefined index: sales_model" and pretty much everything else within the first query, can anyone point out where I am going wrong?

"sales_list" Table

+--------------------------------------------------------------------------------------------------------------------------+
| sales_list                                                                                                               |
+------+--------------------------+--------------------------+------------------------+-------------+----------------------+
| sales_id | users_sales_guild_id | sales_customer_firstname | sales_customer_surname | sales_model |  sales_entry_date    |
+----------+----------------------+--------------------------+------------------------+-------------+----------------------+
| 1        | 1234                 | Jane                     | Smith                  | Ford        | 2013-12-02 12:00:00  |
| 2        | 5678                 | John                     | Chan                   | Mazda       | 2013-12-03 12:00:00  |
| 3        | 5678                 | Kevin                    | Chan                   | Fiat        | 2013-12-04 12:00:00  |
| 4        | 1234                 | Malcom                   | Smith                  | Nissan      | 2013-12-05 12:00:00  |
+----------+----------------------+--------------------------+------------------------+-------------+----------------------+

"accessories_orders" table

+-------------------------------------------------------------------------------------------------------------------------+
| accessories_orders                                                                                                      |
+-----------------------+----------------------+----------+--------------------------+-------------------------+----------+
| accessories_orders_id | users_sales_guild_id | sales_id | accessories_orders_total | accessories_orders_date | shipped  |  
+-----------------------+----------------------+----------+--------------------------+-------------------------+----------+
| 1                     | 1234                 | 1        | 200.00                   | 2013-12-02 12:00:00     | Pending  |
| 2                     | 5678                 | 2        | 350.00                   | 2013-12-03 12:00:00     | Pending  | 
| 3                     | 5678                 | 3        | 100.00                   | 2013-12-03 12:00:00     | Pending  |
+-----------------------+----------------------+----------+--------------------------+-------------------------+----------+

EDITED and UPDATED Code

<?php
require_once ('database.php'); // Connect to the database.

$query = " SELECT sl.sales_model, sl.sales_customer_firstname, sl.sales_customer_surname, ao.accessories_orders_total, ao.shipped, 
       COALESCE(ao.shipped)
       FROM sales_list sl
       LEFT JOIN accessories_orders ao ON(ao.sales_id = sl.sales_id)
       WHERE sl.users_sales_guild_id ='".$_SESSION['users_sales_guild_id']."' 
       ORDER BY 
     ".$order_by." LIMIT ".$start.", ".$display;

$result = @mysql_query ($query); // Run the query.

echo '<table width="610" cellspacing="1" cellpadding="5" style="font-size:11px;">
<tr>
<td align="center">Model </td>
<td align="center">Customer Name</td>
<td align="center">Accessories Total</td>
<td align="center">Status</td></tr>';

$bg = '#ffffff'; // Set the background color.
while ($row = mysql_fetch_array($result, MYSQL_ASSOC)) {

$status = $row['shipped'];

$bg = ($bg=='#e1e3e6' ? '#cdcdcf' : '#e1e3e6'); // Switch the background color.   
echo '<tr bgcolor="' . $bg . '">';
echo  '<td align="center">' . $row['sl.sales_model'] . '</td>';
echo  '<td align="center">' . $row['sl.sales_customer_firstname'] . ' ' . $row['sl.sales_customer_surname'] . '</td>';
echo  '<td align="center">$' . $row['acc.accessories_orders_total'] . '</td>';

$str = '<td align="center">';
if($status == 'Pending') {
 $str .=' Pending</td></tr>';
}
else {
 $str .='<strong><a href="add_accessories_sales.php?sid=' . $row['sl.sales_id'] . '">Add</a></strong></td></tr>'; 
}   
echo $str;
}

echo '</table>';
mysql_free_result ($result); // Free up the resources.
mysql_close();  //Close the database connection.
?>

Answer 1

Your query needs to be more like this:

SELECT sl.sales_model, sl.sales_customer_firstname, sl.sales_customer_surname, ao.accessories_orders_total, COALESCE(ao.shipped, 'Add') status
FROM sales_list sl
LEFT JOIN accessories_orders ao ON(ao.sales_id = sl.sales_id)
WHERE sl.users_sales_guild_id = 1234;

The LEFT JOIN is the key here. It allows a row to be returned with the data from sales_list even if there is no corresponding entry in accessories_orders .

See this fiddle for a working example: http://sqlfiddle.com/#!2/f7d3d/4

As others have already stated, you should be using the mysqli function set as opposed to the mysql function set.

Answer 2

First, you should not be including the table names. Example:

//wrong
echo  '<td align="center">' . $row['sl.sales_model'] . '</td>';

//correct
echo  '<td align="center">' . $row['sales_model'] . '</td>';

Second, you should not be using mysql unless you are using an outdated version of PHP. Switch to mysqli or PDO .

Third, you have no error handling to tell you whether your query is successful or not. In fact, you have the opposite of error handling, because you are trying to use the @ operator to suppress your errors. Instead, you should do something like this:

//assuming you switch to mysqli
mysqli_query("SELECT acc.accessories_orders_id, acc.users_id, acc.sales_id, 
      acc.accessories_orders_total, acc.accessories_orders_date, acc.shipped,
      acc.timestamp, sl.sales_id
      FROM accessories_orders AS acc, sales_list AS sl
      WHERE acc.sales_id = sl.sales_id");
if(mysqli_error()) {
    throw new Exception(mysqli_error(), mysqli_errno());
}

If you do this, your mysql errors will be logged in the same place as your php errors. You will then be able to tell whether any of your trouble is coming from the query being malformed.