SQL语法错误附近

Question

我正在使用模型来运行这样的查询：

    $tickerHigh = $this->model->ticker('price',$market,'AND buysell=buy','ORDER BY PRICE DESC');

这是我的模特;

    $tickersHigh = $this->db->prepare("SELECT ".$type." FROM trades WHERE market=? " . $buysell  . $order . "");
    $tickersHigh->execute(array(strtolower($market)));
    $tickerHigh = $tickersHigh->fetch();
    if($tickerHigh){
    return $tickerHigh->{$type};    
    }

我收到以下错误：

  

警告：PDOStatement :: execute（）：SQLSTATE [42000]：语法错误或   访问冲突：1064您的SQL语法有错误;检查   手册，对应右边的MySQL服务器版本   语法使用附近＆＃39; BY PRICE DESC＆＃39;

中的第1行

我不确定为什么？

Answer 1

只需在ORDER BY之前和AND buysell=buy之前添加一个空格，如下所示：

$tickerHigh = $this->model->ticker("price",$market," AND buysell='buy'"," ORDER BY PRICE DESC");