使用Laravel Eloquent选择多个表

Question

I have 3 tables - users, roles, and role_user. Each user is assigned to a role in the role_user table and the list of roles is found on the roles table. I want to select all users with role id of 12. I am currently doing this with the query builder but I need it to be in eloquent format. I am not really good with Laravel eloquent, please I need help in convert the queries to eloquent. This is what I am currently doing:

 $users = DB::table('users')
            ->join('role_user', 'users.id', '=', 'role_user.user_id')
            ->join('roles', 'roles.id', '=', 'role_user.role_id')
            ->where('roles.id', '=', 12)
            ->get();

Answer 1

To run your same DB query in an eloquent format, you would have to do the following:

1. You should have a User model created which should be created with your project if you enabled laravel authentication which you could read more on here. If not you have to create your Models.

2. To use the Models in your controller or Class, you have to enable it in your php file:

   use App\User;

3. Run your reference to the User model like so.

   $users = User::join('role_user','users.id', '=', 'role_user.user_id') ->join('roles', 'roles.id', '=', 'role_user.role_id') -> where('roles.id', '=', 12) ->get();

$users will now be a collection and subject to all the great methods available with a collection.

I suggest taking some time to run through a free video tutorial on laracast to really understand how Model's are used with Eloquent. Additionally would be good to review the out of the box Auth features available. I tend to make all my calls to roles using Auth. Hope this helps.