Eloquent one to many relationship not working - laravel

Question

I'm stuck for hours with one of those issues where a fresh set of eyes might help. I just can't understand what's missing.
I'm connecting a model called User_ativo and defining two one-to-many relations to models Instituicao and Tipo_Ativo.
My database is simple.
Table user_ativo has columns "tipo_ativo_id" and "instituicao_id". I have a test row where both are set to 1. Both my tables instituicoes and tipo_ativos have only "id" and a string field "nome" (name). Both have a record with id == 1.
User_ativo.php:
<?php
namespace App;
use Illuminate\Database\Eloquent\Model;
class User_ativo extends Model
{
public function tipo(){
return $this->belongsTo('App\Tipo_ativo');
}
public function instituicao(){
return $this->belongsTo('App\Instituicao');
}
}
Instituicao.php
namespace App;
use Illuminate\Database\Eloquent\Model;
class Instituicao extends Model
{
protected $table = 'instituicoes';
public function user_ativos(){
return $this->hasMany('App\User_ativo');
}
}
Tipo_ativo.php
<?php
namespace App;
use Illuminate\Database\Eloquent\Model;
class Tipo_ativo extends Model
{
protected $table = 'tipo_ativos';
public function user_ativos(){
return $this->hasMany('App\User_ativo');
}
}
My controller method that fetches the date goes as follow:
public function index()
{
$ativos = User_ativo::with('tipo', 'instituicao')->get();
return view('ativos.index', compact('ativos'));
}
Now here's where it gets interesting, for some reason I can't figure out, when I echo the $ativos variable in my view I get this:
[{"id":1,"user_id":1,"instituicao_id":1,"tipo_ativo_id":1,"tipo":null,"instituicao":{"id":1,"nome":"Banco do Brasil"}}]
So, weirdly my relationship with the Instituicao model works, but the one with Tipo_ativo returns null.
I'm pretty confident someone will point out some dumb and obvious mistake in all of this, but I can't for the life of me understand why one works and the other doesn't since they're pretty much the same thing.

Answer 1

Your relationships names are not according to laravel convention.
Read below function and provide foreign_key and local_key/owner_key to your relationships then it will work
public function belongsTo($related, $foreignKey = null, $ownerKey = null, $relation = null){}
If we do not follow laravel convention while creating relationships then we have to tell it that these are the foreign and local keys that should be used.
Read more here
class User_ativo extends Model{
public function tipo(){
return $this->belongsTo('App\Tipo_ativo','user_ativo_id'); //second parameter is foreign_key_of_User_avito_table_here
}
public function instituicao(){
return $this->belongsTo('App\Instituicao','user_ativo_id'); //second parameter is foreign_key_of_User_avito_table_here
}
}
class Instituicao extends Model
{
protected $table = 'instituicoes';
public function user_ativos(){
return $this->hasMany('App\User_ativo','instituicao_id'); //second parameter is foreign key of Instituicao model
}
}
class Tipo_ativo extends Model
{
protected $table = 'tipo_ativos';
public function user_ativos(){
return $this->hasMany('App\User_ativo','tipo_ativo_id'); //second parameter is foreign key of Tipo_ativo model.
}
}