错误mysqli_fetch_array（）期望参数1为mysqli_result，布尔值在

Question

您想帮助我修改代码吗？在SQL中联接表时遇到障碍。这是我的代码：

<?php

include_once ('config.php');


$query = "SELECT tb_m_price.price, tb_m_route.location_id, tb_m_location.pool_name_id, 
          tb_m_pool.pool_name
          FROM tb_m_price
          INNER JOIN tb_m_route ON tb_m_route.price_id = tb_m_price.price_id
          INNER JOIN tb_m_location ON tb_m_location.location_id = tb_m_route.location_id
          INNER JOIN tb_m_pool ON tb_m_pool.pool_id = tb_m_location.pool_id
          LEFT JOIN (
            SELECT class_id
            FROM tb_m_bus
            ON tb_m_class.class_id = tb_m_bus.class_id GROUP BY tb_m_class.class_name

          )";

$result = mysqli_query ($con, $query);
$array_data = array();

while($baris = mysqli_fetch_assoc($result)){
    $array_data [] = $baris;

}

echo json_encode `enter code here`($array_data);

?>

我在行中出错：

while($baris = mysqli_fetch_assoc($result)){
        $array_data [] = $baris;
    }

提前谢谢