Laravel relations in multiple model with belongsToMany and hasMany

Question

I am working on an eCommerce application.

I have 3 models. Product, Color, ProductImage.

The relation between Product and Color is: belongsToMany

<?php

namespace App\Entities\Product;

use Illuminate\Database\Eloquent\Model;

class Product extends Model
{
    /**
     * A product has many colors.
     *
     * @return \Illuminate\Database\Eloquent\Relations\BelongsToMany
     */
    public function colors()
    {
        return $this->belongsToMany(Color::class);
    }
}

The relation between Color and ProductImage is: hasMany

<?php

namespace App\Entities\Product;

use Illuminate\Database\Eloquent\Model;

class Color extends Model
{
    /**
     * A color has many images.
     *
     * @return \Illuminate\Database\Eloquent\Relations\HasMany
     */
    public function images()
    {
        return $this->hasMany(ProductImage::class);
    }
}

Question is how to make a relation between the Product and ProductImage model?

How to design the product_images table?

id, color_id, image

like this?

my use case is, I will make a slider on a single product page. There will be a Color select option. If a user selects a color, need to load product images associate with that selected color.

Appreciate your help :)

Does this answer your question? [Laravel 5 eloquent hasManyThrough / belongsToManyThrough relationships](https://stackoverflow.com/questions/35306242/laravel-5-eloquent-hasmanythrough-belongstomanythrough-relationships) — D Malan, Jun 01 '20 at 08:09
@DelenaMalan Thanks for your reply. I will definitely check that answer. — Eliyas Hossain, Jun 01 '20 at 08:22

Ashraf789 · Accepted Answer · 2020-06-01T23:00:06.987

I am also working on an e-commerce project and I have designed my database like below.

A product has multiple product colors but a product color belongs to only one product. product id and color together a compound key(unique) of the product_colors table.

If you have a product T-shirt which id is 101 which product color is red then together 101 and red are a unique product_color.

Product_image belongs to the product and product_colors table. Together product_id and product_color_id are composite key. In case if you have multiple images for the same product id and color then you can save the image as JSON data. which I did for my application.

Although I have designed my database like fig 01. But if we want to separate the colors table then we could design the database like this.

V-K · Answer 2 · 2020-06-01T09:53:43.703

0

If you need only productImages, you can use belongsToManyThrough. But if you need colors and productImages you can do it through the dot.

$product->load('colors.images');

UPD Read your description, in my point of view, table images should have two keys product_id and color_id. And then do something like this:

public function images()
{
    return $this->hasMany(ProductImage::class);
}

public function current_image(int $color_id)
{
    return $this->hasOne(ProductImage::class)->where('color_id', $color_id);
}

edited Jun 01 '20 at 09:53

answered Jun 01 '20 at 08:33

V-K

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Updated question, how to design `product_images` table? – Eliyas Hossain Jun 01 '20 at 09:40
As `Product` has many `Colors` and `Color` has many `Products`, so multiple `color_id` will be there in the `product_images` table. Then how to get a single `product` related images without `product_id` or something? – Eliyas Hossain Jun 01 '20 at 09:51

Laravel relations in multiple model with belongsToMany and hasMany

2 Answers2