Question

我正在尝试创建一个供我内部使用的论坛。

我为帖子设置了类别，因为我希望能够控制人们看到的类别。

输出代码为：

$data_query = mysqli_query($this->con, "SELECT * FROM posts WHERE deleted = 'no' ORDER BY id DESC");

我的想法是这样的：

 $cat_query = mysqli_query($this->con, "SELECT subs FROM users WHERE  username='$userLoggedIn'");
    $cat_array = mysqli_fetch_array($cat_query);
    $c_arr = explode(",", $cat_array);
    $post_cat = mysqli_query($this->con, "SELECT post_category FROM posts WHERE deleted='no'");

if(in_array($post_cat, $c_arr){
$data_query = mysqli_query($this->con, "SELECT * FROM posts WHERE (post_category=$post_cat AND deleted = 'no') ORDER BY id DESC");
}

然而，当我这样做时，它不起作用。

基本上我需要data_query只返回categories数组中类别的帖子。我无法弄明白。

编辑：数据库中的表结构

用户表：

   CREATE TABLE `users` (
  `id` int(11) NOT NULL AUTO_INCREMENT,
  `first_name` varchar(25) NOT NULL,
  `last_name` varchar(25) NOT NULL,
  `username` varchar(100) NOT NULL,
  `email` varchar(100) NOT NULL,
  `password` varchar(255) NOT NULL,
  `signup_date` date NOT NULL,
  `profile_pic` varchar(255) NOT NULL,
  `num_posts` int(11) NOT NULL,
  `num_likes` int(11) NOT NULL,
  `user_closed` varchar(3) NOT NULL,
  `friend_array` text NOT NULL,
  `city` text NOT NULL,
  `state` text NOT NULL,
  `country` text NOT NULL,
  `subs` varchar(500) NOT NULL,
  PRIMARY KEY (`id`)
   ) ENGINE=MyISAM  DEFAULT CHARSET=latin1;

帖子表：

   CREATE TABLE `posts` (
  `id` int(11) NOT NULL AUTO_INCREMENT,
  `body` text NOT NULL,
  `added_by` varchar(60) NOT NULL,
  `user_to` varchar(60) NOT NULL,
  `date_added` datetime NOT NULL,
  `user_closed` varchar(3) NOT NULL,
  `deleted` varchar(3) NOT NULL,
  `likes` int(11) NOT NULL,
  `post_category` varchar(50) NOT NULL,
  `image` varchar(500) NOT NULL,
  PRIMARY KEY (`id`)
   ) ENGINE=MyISAM  DEFAULT CHARSET=latin1

希望这有帮助

Answer 1

尝试在一个查询中编写逻辑，在数据库端执行逻辑时不要使用php函数

$query = "SELECT * FROM posts WHERE deleted='no' AND post_category IN (SELECT subs FROM users WHERE  username='$userLoggedIn' ORDER BY id DESC)";
$result = mysqli_query($this->con, $query);

修改

首先，我要说存储逗号分隔字符串是非常糟糕的做法。列表在一行中，您应该为subs创建新表。

但在这种情况下你应该这样做：

<?php $cat_query = mysqli_query($this->con, "SELECT subs FROM users WHERE username='$userLoggedIn'"); if($cat_query){ $row = mysqli_fetch_assoc($car_query); $subs = $row['subs']; $post_cat_query = "SELECT post_category FROM posts WHERE deleted='no'"; $result = mysqli_query($this->con, $post_cat_query); if($result){ $c_arr = array(); while($row = mysqli_fetch_assoc($result)){ array_push($c_arr, $row['post_category']); } if(in_array($post_cat, $c_arr){ $data_query = mysqli_query($this->con, "SELECT * FROM posts WHERE (post_category=$post_cat AND deleted = 'no') ORDER BY id DESC"); } }

使用in_array控制论坛帖子类别的输出

1 个答案: