How to Join Three Tables in Laravel for a Twitter-like Feed?

Laravel Join with 3 Tables

To join three tables in Laravel for a Twitter-like feed, the join query can be constructed as follows:

$shares = DB::table('shares')
    ->join('users', 'users.id', '=', 'shares.user_id')
    ->join('followers', 'followers.user_id', '=', 'users.id')
    ->where('followers.follower_id', '=', 3)
    ->get();

This query joins the shares, users, and followers tables based on the conditions specified in the join clauses.

Another approach is to use models instead of raw queries for a more object-oriented approach. Here is an example using models:

// Define User Model
class User extends Model {
    public function shares() {
        return $this->hasMany('Share');
    }
    public function followers() {
        return $this->belongsToMany('User', 'follows', 'user_id', 'follower_id');
    }
    public function followees() {
        return $this->belongsToMany('User', 'follows', 'follower_id', 'user_id');
    }
}

// Define Share Model
class Share extends Model {
    public function user() {
        return $this->belongsTo('User');
    }
}

// Model Usage
$my = User::find('my_id');

$shares = Share::with('user')
    ->join('follows', 'follows.user_id', '=', 'shares.user_id')
    ->where('follows.follower_id', '=', $my->id)
    ->get('shares.*');

foreach ($shares as $share) {
    echo $share->user->username;
}

By using this model approach, you can retrieve all shares from users that the logged-in user follows, eagerly loading the user who created the share.

The above is the detailed content of How to Join Three Tables in Laravel for a Twitter-like Feed?. For more information, please follow other related articles on the PHP Chinese website!