PHP 从数据库中以逗号分隔的字符串形式导出值

Question

表格如下所示:

virtuemart_customfield_id___|___virtuemart_product_id___|____custom_value___
                        1   |                   4346    |           45
                        2   |                   4346    |           46
                        3   |                   4347    |           45

此函数按原样正常工作。

function getSizes($product_id){
    global $mainframe;
    $db = &JFactory::getDBO();
    $sql = 'SELECT * FROM `#__virtuemart_product_customfields` WHERE `virtuemart_product_id` ='.$product_id.'';
    $db->setQuery($sql);
    $result=$db->loadObjectList();
    return $result;
}

这是将调用函数并从数据库中获取数据的代码，并尝试用逗号分隔我需要的值。

$records = $this->getSizes($product_id);
$product_size = '';
foreach ($records as $value){
    $size = $value->custom_value;
    if ($product_size == '') {
        $product_size .= $size;
    } else {
        $product_size .= ", " .$size;
}

问题似乎出在这段代码的某处，但我不知道在哪里...任何帮助将非常感激!提前致谢!

Answer 1

尝试这种方式(首先在没有连接的情况下分配给 $size)

$records = $this->getSizes($product_id);
$product_size = '';
foreach ($records as $value){
   $size = $value->custom_value;
   if ($product_size == '') {
       $product_size = $size;
   } else {
       $product_size .= ", " .$size;
   }
}