忽略MySQL JOIN查询中的空结果

我有一个MySQL连接查询，该查询很好地运行 (免责声明:摘自教程) :

I have a MySQL join query which works well (disclaimer: taken from tutorial):

<?php
    $connection = mysql_connect("localhost", "root", "test") or die("Error connecting to database");
    mysql_select_db("products90", $connection);
    $result = mysql_query("SELECT * FROM buyers LEFT JOIN products USING (id);", $connection) or die("error querying database");
    $i = 0;
    while($result_ar = mysql_fetch_assoc($result)){
    ?>
    <table>
    <tr <?php if($i%2 == 1){ echo "class='body2'"; }else{echo "class='body1'";}?>>
    <td>
    <?php echo $result_ar['buyer_name']; ?></td>
    <td>
    <?php echo $result_ar['manufacturer']; ?>
    </td>
    <td>
    <?php echo $result_ar['product_name']; ?>
    </td>
    </tr>
    </table>
    <?php
    $i+=1;
    }
    ?>

但是，如果我希望它忽略NULL结果，那么我需要对JOIN做什么，哪种类型合适?

However, if I wanted it to ignore NULL results, what would I need to do with the JOIN, which type is appropriate?

我在Google上进行了查看，但不确定从何处着手.

I had a look on Google, but am not sure where to proceed from here.