Laravel 5.3 Constraining Eager Loads not working

问题

I have two model User and Profile in one to one relationship.

I want to retrieve all user where profile.status == TRUE using following code.

$users = User::with(['profile' => function ($query) {
        $query->where('status', TRUE);
    }])->get();


    dd(count($users)); //50 

I have 50 users and only among of them only 3 has status == TRUE. But always it display 50.

回答1:

You are getting 50 users because you are applying condition to profile. dd($user->profile) you will get only the records of the profile whose status is true.

Use whereHas():

$users = User::whereHas('profile', function ($query) {
        $query->where('status', TRUE);
    })->get();

dd(count($users));

回答2:

If you want to make it work with single Query, you can use Query Builder join like

\DB::table('users')->join('profile', function ($join){
                        $join->on('users.id', '=', 'profile.user_id')->where('profile.status', '=',TRUE);
                    })->get();

回答3:

You said you're having N+1 problem, so you need to use both whereHas() and with() like this to get users with profiles and to solve N+1 problem:

$users = User::whereHas('profile', function ($query) {
        $query->where('status', TRUE);
    })
    ->with('profile')
    ->get();

来源：https://stackoverflow.com/questions/40797538/laravel-5-3-constraining-eager-loads-not-working