How do you check "if not null" with Eloquent?

Eloquent has a method for that (Laravel 4.*/5.*);

Model::whereNotNull('sent_at')

Laravel 3:

Model::where_not_null('sent_at')

If you wanted to use the DB facade:

DB::table('table_name')->whereNotNull('sent_at')->get();

If someone like me want to do it with query builder in Laravel 5.2.23 it can be done like ->

 $searchResultQuery = Users::query(); 
 $searchResultQuery->where('status_message', '<>', '', 'and'); // is not null
 $searchResultQuery->where('is_deleted', 'IS NULL', null, 'and'); // is null 

Or with scope in model :

public function scopeNotNullOnly($query){

    return $query->where('status_message', '<>', '');
}

We can use

Model::whereNotNull('sent_at');

Or

Model::whereRaw('sent_at is not null');