Question

我正在尝试运行一个函数，该函数在数据库表中查询最接近变量mba_score的数值$runscore。我的功能看起来像这样：

public function get_player($runscore)
{
   $per = $this
             ->db
         ->select('mba_id, abs($runscore - mba_score) as mba_rate', FALSE)
         ->order_by('mba_rate', 'ASC')
         ->get('nba_scores');
         ->limit(1);

        if ($per->num_rows > 0) {
            $p = $per->row_array();
            return $p['nba_id'];
        }
        return false;           
        }

我得到的错误是：

"Error Number: 1054

Unknown column '$runscore' in 'field list'"

我尝试过多次编写和重写这段，并且无法获得结果。

Answer 1

使用双引号：

select("mba_id, abs($runscore - mba_score) as mba_rate", FALSE)

使用单引号，变量$ runscore不会替换为其值。如果要使用单引号，则应使用连接：

select('mba_id, abs('.$runscore.' - mba_score) as mba_rate', FALSE)

Answer 2

变化：

->select("mba_id, abs($runscore - mba_score) as mba_rate", FALSE) //use doube quote

Answer 3

您应该在变量中使用

 ->select("mba_id, abs('".$runscore."' - mba_score) as mba_rate", FALSE)
         ->order_by('mba_rate', 'ASC')
         ->get('nba_scores');
         ->limit(1);

选择最接近变量的值

3 个答案: