android访问自己写的页面出现code500错误是怎么回事呢？

我在我写的页面加上插入upload表的代码后，android访问会出现code500，如果注释掉的话就正常返回json信息，可是我在common.php里没有找到显示code500错误的代码，不知道什么原因，插入upload表代码如下：(注释处会引起500错误)

do{

    $stateInfo="";

    $file=$_FILES['uploadedfile'];

    if (!$file) {

$stateInfo ="ERROR_FILE_NOT_FOUND";

break;

    }

    if ($file['error']) {

$stateInfo = "error";

break;

    } else if (!file_exists($file['tmp_name'])) {

$stateInfo = "ERROR_TMP_FILE_NOT_FOUND";

break;

    } else if (!is_uploaded_file($file['tmp_name'])) {

$stateInfo = "ERROR_TMPFILE";

break;

    }

    $oriName= $file['name'];

    $fileSize = $file['size'];

    $fileLongType = $file['type'];

    $fileType = strtolower(strrchr($oriName, '.'));

    $fullName  = $file['name'];

    $filePath  = "./upload/doctorfile/".$DBUser['ID']."/";

    $fileName  = $file['name'];

    $dirname  = "./upload/doctorfile/".$DBUser['ID']."/";

    if($fileSize > 10240000){

$stateInfo = "ERROR_SIZE_EXCEED";

break;

    }

$target_path  = "./upload/doctorfile/".$DBUser['ID']."/";//接收文件目录  

$target_path = $target_path . basename( $_FILES['uploadedfile']['name']); 

$SHA1=sha1_file($_FILES['uploadedfile']['tmp_name']);

$MD5=md5_file($_FILES['uploadedfile']['tmp_name']);

    if(move_uploaded_file($_FILES['uploadedfile']['tmp_name'], $target_path)) { 

            //移动成功

    $stateInfo = "SUCCESS";

/*

$DB->query('INSERT INTO ' . $this->Prefix . 'upload(`UserName`, `FileName`, `FileSize`, `FileType`, `SHA1`, `MD5`, `FilePath`, `Description`, `Category`, `Class`, `PostID`, `Created`) VALUES(:UserName, :FileName, :FileSize, :FileType, :SHA1, :MD5, :FilePath, :Description, :Category, :Class, :PostID, :Created)', array(

'UserName' => $UploadUserName,

'FileName' => htmlspecialchars($oriName),

'FileSize' => $fileSize,

'FileType' => $fileLongType,

'SHA1' => $SHA1,

'MD5' => $MD5,

'FilePath' => $filePath,

'Description' => '',

'Category' => '',

'Class' => 'Forum',

'PostID' => 0,

'Created' => time()

));

*/

    }  else{  

//移动失败

$stateInfo = "ERROR_FILE_MOVE";

    }  

}while(false);