php - 显示 MySQL 表中的行时出错

Question

当满足条件(状态=“无传输”)时，我试图从表中获取行，但即使应该显示行(计数为 1 或更多)，也没有显示任何内容。

         if($query['num'] == 0){
            echo "<p>No shopping orders on transit</p>";
          }else{

              $sql = "SELECT *, FORMAT(total, 0) AS total, FORMAT(grand_total, 0) AS grand_total FROM shipping_details WHERE status = 'no transit' ORDER BY order_id DESC";

              foreach ($db->query($sql) AS $query){
              echo" Show some results ";

              $select = "SELECT * FROM shipping_order WHERE order_id = :order_id";

                foreach ($db->query($select, array('order_id' => $query['order_id'])) AS $items){

                echo"
                Some results
                ";
                //Foreach ends
              }
            }
         }

Answer 1

您没有充分展示我们可以告诉您使用哪个代码库连接到数据库(MySQLi、mysql_ 或 PDO)，因此下面的代码可能需要一些调整。

问题基本上是您从未检索过数据库结果。相反，您尝试循环执行查询本身。

改变

$sql = "SELECT *...";
foreach ($db->query($sql) AS $query)...

至

$sql = "SELECT *...";
$result = $db->query($sql); //execute the query
if(!$result) die($db->error); //exit and show error if query failed

//now we can fetch the results one at a time and loop through them
//this line may need to be adjusted if you're not using MySQLi
while($row = $result->fetch_assoc())...

在 while 循环中，$row 将包含数据库记录中的值。使用 print_r($row) 了解其形状。