Mount Array with categories and subcategories that are in the same table

Question

I am trying to assemble an array, but I am not getting, before the following table, I need to assemble the array as in the example below the photo.

6.x Standard design

in the'categoria_id 'columns which is null' are main categories. And the 'categorias_id with id, are the subcategories, with the id of the main category, I need something with this example that I set below.

$categorias = Categorias::orderBy('id', 'ASC')->get();

$categoria = $categorias->where('categoria_id', '=', null)->toArray();

$subcategoria = $categorias->where('categoria_id', '!=', null)->toArray();

I even separated, but I can’t put them together, as shown in the example below.

Array
(
    [0] => Array
        (
            [id] => 1
            [categoria] => Lanches
            [categoria_id] => 
            [status] => 0
            [ordem] => 
            [subcats] => Array
               (
                     [3] => Array
                         (
                             [id] => 5
                             [categoria] => Lanches Tradicionais
                             [categoria_id] => 1
                             [status] => 0
                             [ordem] => 
                         )

                     [4] => Array
                         (
                             [id] => 6
                             [categoria] => Lanches Gourmet
                             [categoria_id] => 1
                             [status] => 0
                             [ordem] => 
                         )

                     [5] => Array
                         (
                             [id] => 7
                             [categoria] => Lanches Caseiros
                             [categoria_id] => 1
                             [status] => 0
                             [ordem] => 
                         )

                )
        )

    [1] => Array
        (
            [id] => 2
            [categoria] => Porções
            [categoria_id] => 
            [status] => 0
            [ordem] => 
        )

    [2] => Array
        (
            [id] => 4
            [categoria] => Sucos
            [categoria_id] => 
            [status] => 0
            [ordem] => 
        )

)

I’ve tried to ride in various ways, but no success, I don’t know what else to do.

Answer 1

1. According to the first example:

First you need to filter the data you have categoria_id === null, example:

$arrayCategoria = array_filter($array, function ($item) {
  return empty($item['categoria_id']);
});

and then with the categories already separated you need to iterate on the items that are the categories and search in the array main Sub Categories with other array_filter:

for ($i = 0; $i < count($arrayCategoria); $i++) {
  $id = $arrayCategoria[$i]['id'];
  $arrayCategoria[$i]['cats'] = array_filter(
    $array,
    function ($item) use ($id) {
      return $item['categoria_id'] === $id;
    }
  );
}

---

Complete code:

<?php    
$array = [
  ['id' => 1, 'categoria' => 'Lanches', 
   'categoria_id' => null, 'status' => 0, 'ordem' => null],
  ['id' => 2, 'categoria' => 'Porções', 
   'categoria_id' => null, 'status' => 0, 'ordem' => null],
  ['id' => 4, 'categoria' => 'Sucos', 
   'categoria_id' => null, 'status' => 0, 'ordem' => null],
  ['id' => 5, 'categoria' => 'Lanches Tradicionais', 
   'categoria_id' => 1, 'status' => 0, 'ordem' => null],
  ['id' => 6, 'categoria' => 'Lanches Gourmet', 
   'categoria_id' => 1, 'status' => 0, 'ordem' => null],
  ['id' => 7, 'categoria' => 'Lanches Caseiros', 
   'categoria_id' => 1, 'status' => 0, 'ordem' => null],
];   

$arrayCategoria = array_filter($array, function ($item) {
  return empty($item['categoria_id']);
});    

for ($i = 0; $i < count($arrayCategoria); $i++) {
  $id = $arrayCategoria[$i]['id'];
  $arrayCategoria[$i]['cats'] = array_filter(
    $array,
    function ($item) use ($id) {
      return $item['categoria_id'] === $id;
    }
  );
}

echo '<pre>';
print_r($arrayCategoria);
echo '</pre>';

---

Online Link

---

2. With Self Relationship

The other way would be for me the ideal where own Eloquent would solve with a Self Relationship Question I Asked Myself and the answer.

In his Model Categorias add a method:

//relacionamento (auto-relacionamento) item 4 
public function subCategorias()
{
    return $this->hasMany(Categorias::class, 'categoria_id', 'id');
}

and when using make the following code:

Categorias::with('subCategorias')->get();

---

Note: Use the second option is easier to maintain the evolution of the code and item 1. gets to do this code manually