PDO Prepare Statement Limit Not Working

Question

我試圖限制從SQL查詢返回的結果數量，但由於某種原因它返回NULL。如果我刪除了限制，一切正常。我已經在Sequel Pro中測試了這個查詢，並且它在LIMIT中也能正常工作。我在這裏做錯了什麼？

public static function getMostViewedPictures($limit = 5) { 
    $dbh = self::connectToDatabase(); 

    $sql = "SELECT 
       picture.`title`, 
       picture.`description`, 
       picture.`slug`, 
       picture.`image`, 
       picture.`timestamp`, 
       picture.`views`, 
       category.category as category 
      FROM picture 
      LEFT JOIN category 
       ON picture.category_id = category.id 
      ORDER BY picture.views ASC 
      LIMIT 0, :limit"; 

    $sth = $dbh->prepare($sql); 
    $sth->execute(array(':limit' => $limit)); 

    if($results = $sth->fetchAll(PDO::FETCH_OBJ)) { 
     $pictures = array(); 

     foreach($results as $result) { 
      $pictures[] = new Picture(
       $result->title, 
       $result->description, 
       $result->slug, 
       $result->timestamp, 
       $result->category, 
       $result->views, 
       $result->image 
      ); 
     } 

     return $pictures; 
    } else { 
     return null; 
    } 
} 

Answer 1

已解決。

$sth->bindParam(':limit', $limit, PDO::PARAM_INT);