错误的XML格式输出 - Incorrect XML format output

下面提到的代码能够从数据库中获取数据，输出也是XML格式，但我想要的顺序是不正确的。

<?php
    $config['mysql_host'] = "localhost";
    $config['mysql_user'] = "market";
    $config['mysql_pass'] = "12345";
    $config['db_name']    = "marketing";
    $config['table_name'] = "data";
    $root = customers; 
    //connect to host
    mysql_connect($config['mysql_host'],$config['mysql_user'],$config['mysql_pass']);
    //select database
    @mysql_select_db($config['db_name']) or die( "Unable to select database");
    $xml          = "<?xml version='"1.0'" encoding='"UTF-8'"?>";
    $root_element = $root; 
    $xml         .= "<$root_element>";
    //select all items in table
    $sql = "SELECT * FROM ".$config['table_name'];
    $result = mysql_query($sql);
    if (!$result) {
        die('Invalid query: ' . mysql_error());
    }
    if(mysql_num_rows($result)>0)
    {
       while($result_array = mysql_fetch_assoc($result))
       {
          $xml .= "<".$config['table_name'].">";
          //loop through each key,value pair in row
          foreach($result_array as $key => $value)
          {
             //$key holds the table column name
             $xml .= "<$key>";
             //embed the SQL data in a CDATA element to avoid XML entity issues
             $xml.=$value;
             //and close the element
             $xml .= "</$key>";
          }
          $xml.="</".$config['table_name'].">";
       }
    }
    //close the root element
    $xml .= "</$root_element>";
    //send the xml header to the browser
    header ("Content-Type:text/xml");
    //output the XML data
    echo $xml;
    ?>

电流输出:

<customers>
<data>
<customer>111</customer>
<openingbal>111</openingbal>
<pandl>11</pandl>
<currentbal>111</currentbal>
<time>2015-08-28 04:07:21</time>
</data>
<data>
<customer>111</customer>
<openingbal>111</openingbal>
<pandl>11</pandl>
<currentbal>111</currentbal>
<time>2015-08-28 04:07:21</time>
</data>
</customers>

但是我想要下面的输出，其中id = "something">但上面的代码不产生相同的结果。

<Customers>
  <Customer ID ="111">
    <openingbal>111</openingbal>
    <pandl>11</pandl>
    <currentbal>111</currentbal>
    <time>2015-08-14 03:14:30</time>
  </Customer>
  <Customer Id = "111">
    <openingbal>111</openingbal>
    <pandl>11</pandl>
    <currentbal>111</currentbal>
    <time>2015-08-14 03:14:30</time>
  </Customer>
</Customers>

这就成功了。

<?php
    $config['mysql_host'] = "localhost";
    $config['mysql_user'] = "market";
    $config['mysql_pass'] = "12345";
    $config['db_name']    = "marketing";
    $config['table_name'] = "data";
    $config['main_key'] = "customer";
    $root = 'Customers'; 
    //connect to host
    mysql_connect($config['mysql_host'],$config['mysql_user'],$config['mysql_pass']);
    //select database
    @mysql_select_db($config['db_name']) or die( "Unable to select database");
    $xml          = "<?xml version='"1.0'" encoding='"UTF-8'"?>";
    $root_element = $root; 
    $xml         .= "<$root_element>";
    //select all items in table
    $sql = "SELECT * FROM ".$config['table_name'];
    $result = mysql_query($sql);
    if (!$result) {
        die('Invalid query: ' . mysql_error());
    }
    if(mysql_num_rows($result)>0)
    {
       while($result_array = mysql_fetch_assoc($result))
       {
          $xml .= "<".ucfirst($config['main_key']);
          //loop through each key,value pair in row
          foreach($result_array as $key => $value)
          {
             if ($key == $config['main_key'])  {
                  $xml .= " ID = '"".$value."'">";
             }else    {
                 //$key holds the table column name
                 $xml .= "<$key>";
                 //embed the SQL data in a CDATA element to avoid XML entity issues
                 $xml.=$value;
                 //and close the element
                 $xml .= "</$key>";
             }
          }
          $xml.="</".ucfirst($config['main_key']).">";
       }
    }
    //close the root element
    $xml .= "</$root_element>";
    //send the xml header to the browser
    header ("Content-Type:text/xml");
    //output the XML data
    echo $xml;
    ?>