Laravel 8 Multiple Table Relationship - php

Question

This is a long post, sorry in advance.
I have a couple of questions regarding the diagram below.
How do I create a relationship for these tables? (tried "belongsToMany" and "hasMany")
Should I use Eloquent or Query Builder to get desired result? (image is attached below for desired result)
Is "client_order_items" a pivot table?
How can you distinguish a pivot table? Is it because the table has multiple
foreign keys?
How can I access "images" table from "Manufacturer" model? Can "hasOneThrough / hasManyThrough" achieve this?
Is the desired result achievable purely using Eloquent or DB Query?
//sample:
Manufacturers::find(2)->client_order_items->cars->images->car_image
I tried considering "client_order_items" as a pivot table then making relationships using "belongsToMany" in "Manufacturer", "Car" and "ClientOrder" models.
// App\Model\Manufacturer.php
public function client_orders() {
return $this->belongsToMany(ClientOrder::class,
"client_order_items", "manufacturer_id", "client_order_id")
->withPivot('id', 'quantity', 'car_id');;
}
public function cars() {
return $this->belongsToMany(Car::class,
"client_order_items", "manufacturer_id", "car_id");
}
// App\Model\Car.php
public function client_orders() {
return $this->belongsToMany(ClientOrder::class,
"client_order_items", "car_id", "client_order_id");
}
public function manufacturers() {
return $this->belongsToMany(Manufacturer::class,
"client_order_items", "car_id", "manufacturer_id");
}
// App\Model\ClientOrder.php
public function cars() {
return $this->belongsToMany(Manufacturer::class,
"client_order_items", "client_order_id", "car_id");
}
public function manufacturers() {
return $this->belongsToMany(Manufacturer::class,
"client_order_items", "client_order_id", "manufacturer_id");
}
I also tried "hasMany" relationship:
// App\Model\Manufacturer.php
public function client_order_items() {
return $this->hasMany(ClientOrderItems::class);
}
// App\Model\Cars.php
public function client_order_items() {
return $this->hasMany(ClientOrderItems::class);
}
// App\Model\ClientOrder.php
public function client_order_items() {
return $this->hasMany(ClientOrderItems::class);
}
// App\Model\ClientOrderItems.php
public function car() {
return $this->belongsTo(Car::class);
}
public function manufacturer() {
return $this->belongsTo(Manufacturer::class);
}
public function client_order() {
return $this->belongsTo(ClientOrder::class);
}
My goal is to get the result if i did something like this:
// Manufacturer::find(2)->client_orders
// Desired Result:
[
{
"client_order_id": 88062,
"first_name": "Clark",
"last_name": "Kent",
"order_items": [
{
"client_order_item_id": 37394,
"quantity": 1,
"car_id": 68,
"image": "path_img1"
}
]
},
{
"client_order_id": 60978,
"first_name": "Bruce",
"last_name": "Wayne",
"order_items": [
{
"client_order_item_id": 79913,
"quantity": 1,
"car_id": 68,
"image": "path_img1"
},
{
"client_order_item_id": 84743,
"quantity": 1,
"car_id": 95,
"image": "path_img2"
}
]
}
]
But the result I'm currently getting (with "belongsToMany") is:
// Manufacturer::find(2)->client_orders
// Current Result:
[
{
"id": 88062,
"first_name": "Clark",
"last_name": "Kent",
"pivot": {
"manufacturer_id": 2,
"client_order_id": 88062,
"id": 37394,
"quantity": 1,
"car_id": 68
}
},
{
"id": 60978,
"first_name": "Bruce",
"last_name": "Wayne",
"pivot": {
"manufacturer_id": 2,
"client_order_id": 60978,
"id": 79913,
"quantity": 1,
"car_id": 68
}
},
{
"id": 60978,
"first_name": "Bruce",
"last_name": "Wayne",
"pivot": {
"manufacturer_id": 2,
"client_order_id": 60978,
"id": 84743,
"quantity": 1,
"car_id": 95
}
}
]
Sorry again for the long post.
Thank you in advance.

Answer 1

After experimenting and reading for couple of hours, I was able to get the result I want.
Making the relationships:
Manufacturer model has "belongsToMany" relationship with "ClientOrder"
// App\Model\Manufacturer
public function client_orders() {
return $this->belongsToMany(ClientOrder::class, 'client_order_items', 'manufacturer_id', 'client_order_id');
}
"Car" and "Image" model has "hasMany" relationship. This will give us access to "Image" model from "ClientOrderItems" model.
// App\Models\Car
public function image() {
return $this->belongsTo(Image::class);
}
// App\Models\Image
public function cars() {
return $this->hasMany(Car::class);
}
Creating Accessors to Models
In "ClientOrder" model, create an accessor for the "order_items" key. This will fetch rows from "OrderLineItems" that are related to the "manufacturer_id" and "client_order_id".
// App\Models\ClientOrder
protected $appends = ["order_items"];
public function getOrderItemsAttribute() {
$items = ClientOrderItems::where("manufacturer_id", '=', $this->pivot->manufacturer_id)
->where("client_order_id","=",$this->pivot->client_order_id)
->select(["id as client_order_item_id","car_id","quantity"])
->get();
return $items;
}
In "ClientOrderItems" pivot model, create an accessor for the "image".
// App\Models\ClientOrderItems
protected $appends = ["image"];
public function getImageAttribute() {
return Car::find($this->car_id)->image->car_image;
}
The result of the 2 codes above looks something like this:
[
{
"client_order_item_id": 79913,
"quantity": 1,
"car_id": 68,
"image": "path_img1"
},
{
"client_order_item_id": 84743,
"quantity": 1,
"car_id": 95,
"image": "path_img2"
}
]
More on Accessors & Mutators:
https://laravel.com/docs/8.x/eloquent-mutators#accessors-and-mutators
Retrieving Records
To get the "client orders" that are related to manufacturer_id, use:
/// App\Http\Controllers\ManufacturerController;
public function index() {
$client_order = Manufacturer::find($manufacturer_id)->client_orders->unique("id")->values();
}
Above code will only fetch unique rows from "client_orders" table. Appending the related "order_items" for each row with the help of accessors.
[
{
"client_order_id": 88062,
"first_name": "Clark",
"last_name": "Kent",
"order_items": [
{
"client_order_item_id": 37394,
"quantity": 1,
"car_id": 68,
"image": "path_img1"
}
]
},
{
"client_order_id": 60978,
"first_name": "Bruce",
"last_name": "Wayne",
"order_items": [
{
"client_order_item_id": 79913,
"quantity": 1,
"car_id": 68,
"image": "path_img1"
},
{
"client_order_item_id": 84743,
"quantity": 1,
"car_id": 95,
"image": "path_img2"
}
]
}
]