ThinkPHP2.0读取MSSQL提示Incorrect syntax near the keyword 'AS'的解决方法

<?php 
class IndexAction extends Action{ 
  public function index(){ 
    /* 
    $Model = new Model(); 
    $test = $Model->query('select top 10 * from f_city'); 
    dump($test); 
    */ 
    $CityModel = M('city'); 
    $CityModel->find(); 
    dump($CityModel); 
  } 
} 
?>

public function parseLimit($limit) { 
      if(emptyempty($limit)) $limit=1; 
  $limit    =    explode(',',$limit); 
  if(count($limit)>1) 
    $limitStr    =    '(T1.ROW_NUMBER BETWEEN '.$limit[0].' + 1 AND '.$limit[0].' + '.$limit[1].')'; 
      else 
    $limitStr = '(T1.ROW_NUMBER BETWEEN 1 AND '.$limit[0].")"; 
  return $limitStr; 
} 

public function parseLimit($limit) { 
  return ''; 
}

<?php 
class CommonAction extends Action { 
  public $dbsql; 
  function _initialize() { 
    Vendor('adodb5.adodb'); 
    $adodb = ADONewConnection(C('DB_TYPE')); 
    $adodb->Connect(C('DB_HOST'), C('DB_USER'), C('DB_PWD'), C('DB_NAME')); 
    $adodb->SetFetchMode(ADODB_FETCH_ASSOC); 
    $this->dbsql = $adodb; 
  } 
} 
?>

<?php 
class IndexAction extends CommonAction { 
  public function index() { 
    $query = $this->dbsql->Execute('select * from xxx'); 
    while($rows = $query->FetchRow()) { 
        echo $rows['fields']; 
     } 
  } 
} 
?>