Mysqli查询结果返回空，但不应该返回

Question

我直接通过PHP MyAdmin运行查询，它返回1个结果。我错过了什么吗？很清楚，我一定是这样，我不能把它包裹起来！？！

我想我只是厌倦了什么！ 任何帮助将不胜感激： -

$query_road_tax = mysqli_query($conn011, "SELECT * FROM road_tax_pricing WHERE (tax_from_co2 <='$vehicle_co2' AND tax_upto_co2 >='$vehicle_co2'");
$row_road_tax = mysqli_fetch_assoc($query_road_tax);
$Six_Month=$row_road_tax['tax_6month'];
$Twelve_Month=$row_road_tax['tax_12month'];

Answer 1

关闭) and "问题将是

$query_road_tax = mysqli_query($conn011, "SELECT * FROM 
road_tax_pricing WHERE (tax_from_co2 <='$vehicle_co2' AND tax_upto_co2 >='$vehicle_co2')");

Answer 2

试试 - 你可能需要循环打印结果。

$query = "SELECT * FROM road_tax_pricing WHERE (tax_from_co2 <='$vehicle_co2' AND tax_upto_co2 >='$vehicle_co2')";

if($query_road_tax = mysqli_query($conn011, $query)) {
  while ($row = mysqli_fetch_assoc($query_road_tax)) {

      /* print_r($row); */

      printf($row["tax_6month"]);
      printf($row["tax_12month"]);
  }
}