php - mysqli_query 不显示任何结果

Question

我想从 MySQL 表中检索与特定电子邮件匹配的数据。有 2 条记录与此电子邮件相关，但我的屏幕上没有打印任何内容。

<?php

$conn = mysqli_connect('localhost', 'root', '', 'testdrive');


$sql = mysqli_query($conn, 
        'SELECT * FROM products_bought
        where email = "'.mysqli_real_escape_string($conn, "a@gmail.com").'"'
    );
while($row = mysqli_fetch_array($sql)){
    $fullname = $row['fullname'];
    ?>
    <p><?php echo $fullname; ?></p>
    <?php
}

?>

Answer 1

我不知道问题从何而来，但我想帮助你一点:

<?php
   $conn = mysqli_connect('localhost', 'root', '', 'testdrive');
   $sql = mysqli_query($conn,'SELECT * FROM products_bought
    where email = "'.mysqli_real_escape_string($conn, "a@gmail.com").'"');

   if($sql->num_rows > 0){ // Check existence of the data that received
      while($row = mysqli_fetch_array($sql)){
        $fullname = $row['fullname'];
        echo "<p>".$fullname."</p>"; // Why just echoing it in one <?PHP ?>
      }
   } else {
      // If no data sent. then check your db, cause the problems was in your db
   }
?>