Question

我有两个表，posts和likes。我需要创建一个查询使用Eloquent ，它会获取特定user_id所喜欢的所有帖子。

换句话说，它应该是这样的：

SELECT * FROM posts p LEFT JOIN likes l ON p.id = l.post_id WHERE l.user_id = 2 ORDER BY l.created_at DESC

posts表：

+----+---------+------------+-------------+
| id | user_id |  message   | created_at  |
+----+---------+------------+-------------+
|  1 |       2 | Hello!     | <SOME TIME> |
|  2 |       3 | World!     | <SOME TIME> |
|  3 |       2 | Something. | <SOME TIME> |
|  4 |       2 | Another.   | <SOME TIME> |
+----+---------+------------+-------------+

likes表：

+----+---------+---------+-------------+
| id | post_id | user_id | created_at  |
+----+---------+---------+-------------+
|  1 |       1 |       2 | <SOME TIME> |
|  2 |       2 |       2 | <SOME TIME> |
|  3 |       1 |       3 | <SOME TIME> |
|  4 |       3 |       2 | <SOME TIME> |
+----+---------+---------+-------------+

这是我的Post课程：

<?php

class Post extends Eloquent {

    protected $table = 'posts';

    public function likes()
    {
        return $this->hasMany('Like');
    }

}

Like类：

<?php

class Like extends Eloquent {

    protected $table = 'likes';


    public function post()
    {
        return $this->belongsTo('Post');
    }

}

我该怎么做？

Answer 1

这应该有效：

$user_id = //however you get the userid here.

$posts = Post::whereHas('likes', function ($q) use($user_id){
    $q->where('user_id', $user_id);
})->get();

Answer 2

您可以使用Laravel的DB类在两个或多个表上执行连接，以下是您在laravel中执行查询的方式：

$users = DB::table('posts')
        ->leftJoin('likes', 'posts.id', '=', 'likes.post_id')
        ->select('posts.*', 'likes.*')
        ->where('likes.user_id', '=', '2')
        ->orderBy('likes.created_at', 'desc')
        ->get();

不要忘记在控制器顶部使用DB类;

如果你想以雄辩的方式做到这一点，你应该做下面的事情：

$result = Post::whereHas('likes', function ($q) use($user_id)
                {
                   $q->where('user_id', $user_id);
                })
                  ->orderBy('likes.created_at')
                  ->get();

查询列在另一个表

2 个答案: