Issue with Laravel model relationships

Question

I'm trying to retrieve all product categories with all their respective products, one product belongs to one product category and one product category can have many products.

When I retrieve productCategories I get the following error:

 Illuminate \ Database \ QueryException (42S22)
SQLSTATE[42S22]: Column not found: 1054 Unknown column 'products.product_category_id' in 'where clause' (SQL: select * from `products` where `products`.`product_category_id` in (1, 2, 3))

This is my migrations file for product and categories:

<?php


use Illuminate\Support\Facades\Schema;
use Illuminate\Database\Schema\Blueprint;
use Illuminate\Database\Migrations\Migration;


class ProductsAndCategories extends Migration
{
    public function up()
    {
        //CREATE PRODUCT CATEGORIES TABLE
        Schema::create('productcategories', function (Blueprint $table) {
            $table->increments('id');
            $table->string('title');
            $table->string('description')->nullable();
            $table->string('image')->nullable();
            $table->timestamps();
        });

        //  CREATE PRODUCTS TABLE
        Schema::create('products', function (Blueprint $table) {
            $table->increments('id');
            $table->unsignedInteger('productcategory_id')->index();
            $table->foreign('productcategory_id')->references('id')->on('productcategories');
            $table->string('title');
            $table->string('description')->nullable();
            $table->string('body')->default('');
            $table->string('image')->nullable()->default(config('globals.dummy_image'));
            $table->boolean('isVisible')->default(true);
            $table->integer('stockLeft')->default(0);
            $table->decimal('halfPrice', 5,2)->default(0.00);
            $table->decimal('fullPrice', 5,2)->default(0.00);
            $table->decimal('finalPrice', 5,2)->default(0.00);
            $table->timestamps();
        });
    }

    public function down()
    {
        Schema::dropIfExists('products');
        Schema::dropIfExists('productcategories');
    }
}

And my two related models:

Product:

<?php
namespace App\Models;


use Illuminate\Database\Eloquent\Model;


class Product extends Model
{
    protected $table = 'products';

    public function productcategory()
    {
        return $this->belongsTo('App\Models\ProductCategory', 'productcategory_id');
    }
}

ProductCategory:

<?php
namespace App\Models;

use Illuminate\Database\Eloquent\Model;

class ProductCategory extends Model
{
    protected $table = 'productcategories';

    public function products()
    {
        return $this->HasMany('App\Models\Product');
    }
}

Laravel has conventions for doing join guesses - your column naming is non-standard. In Symfony (where laravel has its roots), TitleCase classes get converted to snake case: ProductCategory becomes product_category, therefore in your products() method in ProductCategory, unless you specify the foreignKey column as productcategory_id, it will try to imply the snake case equivalent. — Trent
App\Models\ProductCategory should be just App\YourModel in your Models — Iftikhar uddin

Bhuvanesh Soni Bhuvanesh Soni · Accepted Answer · 2019-03-04T04:20:19

First of all you need to define right keyword for hasMany relation. Change HasMany to hasMany(); and Model look like this:-

<?php
    namespace App\Models;
    use Illuminate\Database\Eloquent\Model;
    class Product extends Model
    {
          protected $table = 'products';
          protected $primary_key = 'product_id';
          public function productcategory()
          {
               return $this->belongsTo('App\Models\ProductCategory', 'productcategory_id');
          } 
    }

and second model look like this: -

<?php
    namespace App\Models;
    use Illuminate\Database\Eloquent\Model;
    class ProductCategory extends Model
    {
         protected $table = 'productcategories';
         protected $primary_key = 'id';
         public function products()
         {
              return $this->HasMany('App\Models\Product', 'id');
         }
    }

and Query will be look like this: -

$product_list = Product::with('productcategory')->get();

this query will give you all records and category of particular record.

Issue with Laravel model relationships

1 Answers