php - 如何使用mysql限制数据库中的所有列

Question

我正在开发图库系统，我想知道如何限制/显示上传到图库/数据库表中的所有图像。我通常不知道这是如何完成的，所以我通常使用大于数据库中列数的数字来显示我的所有列。我很想知道这是如何完成的，以改变我这样做的方法。

下面是我的代码；

<?php
  $image_id = $the_image = $image_des = $time_uploaded = "";
  $gallery = mysqli_query($connect, "SELECT * FROM gallery ORDER BY time_uploaded DESC LIMIT 9000");
  while ($pick = mysqli_fetch_array($gallery, MYSQLI_BOTH)) {
    $image_id = $pick['id'];
    $the_image = $pick['image'];
    $image_des = $pick['description'];
    $time_uploaded = $pick['time_uploaded'];
    echo '<div class="nicdark_margin100">';
      echo '<a href="../img/gallery/'.$the_image.'" title="'.$image_des.'"><img alt="" class="nicdark_radius nicdark_opacity" src="../img/gallery/'.$the_image.'" width="100" height="100" /></a>&nbsp;&nbsp;&nbsp;&nbsp;';
    echo ' </div>';                    
  }
?>

Answer 1

MySQL 在查询中不需要 LIMIT 字段。所以要得到所有的结果

SELECT * FROM gallery ORDER BY time_uploaded DESC

但是，如果您尝试进行分页，则可以结合使用 LIMIT 和 OFFSET

## First Page of 25 images
SELECT * FROM gallery ORDER BY time_uploaded DESC LIMIT 25 OFFSET 0
## Second Page of 25 images (offset by 25)
SELECT * FROM gallery ORDER BY time_uploaded DESC LIMIT 25 OFFSET 25

有关详细信息，请参阅

https://www.w3schools.com/php/php_mysql_select_limit.asp