$ wpdb->結果方法沒有任何結果打印或錯誤

Question

下面的代碼，爲什麼它不顯示任何結果？可能是什麼問題呢？ 感謝您的任何建議

function vendorDatails($param) 
{ 
global $wpdb; 

$query = $wpdb->prepare("SELECT DISTINCT vendor_id FROM {$wpdb->lqrhxf_pv_commission} WHERE order_id = '%d'", $param); 

$result = $wpdb->get_results($query, ARRAY_A); 

     foreach ($result as $row) 
      { 
       echo $row->vendor_id; 
      } 

     echo $result[0]->vendor_id; 

//clean all results 
$wpdb->flush(); 

}

Answer 1

嘗試以下更改的查詢

$query = $wpdb->prepare("SELECT DISTINCT vendor_id FROM $wpdb->lqrhxf_pv_commission WHERE order_id = %d", $param);