Laravel migration can't add foreign key

Question

I'm trying to write a laravel database migration but I'm getting the following error about a foreign key:

  [Illuminate\Database\QueryException]                                                                                                                                                                                                                       SQLSTATE[42000]: Syntax error or access violation: 1072 Key column 'category_id' doesn't exist in table (SQL: alter table `subcategories` add constraint subcategories_category_id_foreign foreign key (`category_id`) references `categories` (`id`))        [PDOException]                                                                                              SQLSTATE[42000]: Syntax error or access violation: 1072 Key column 'category_id' doesn't exist in table  

The categories and subcategories tables do get created but the foreign key doesn't. Here's my migration:

<?php  use Illuminate\Database\Schema\Blueprint; use Illuminate\Database\Migrations\Migration;  class CreateCategoryTable extends Migration {     /**      * Run the migrations.      *      * @return void      */     public function up()     {         Schema::create('categories', function ($table) {             $table->increments('id')->unsigned();             $table->string('name')->unique();         });          Schema::create('subcategories', function ($table) {             $table->increments('id')->unsigned();             $table->foreign('category_id')->references('id')->on('categories');             $table->string('name')->unique();         });     }      /**      * Reverse the migrations.      *      * @return void      */     public function down()     {         Schema::drop('categories');         Schema::drop('subcategories');     } } 

Any ideas? Thanks!

Answer 1

You should create column before creating a foreign key:

$table->integer('category_id')->unsigned(); $table->foreign('category_id')->references('id')->on('categories'); 

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Documentation: http://laravel.com/docs/5.1/migrations#foreign-key-constraints

Answer 2

Laravel 7, 8

As Limon Monte mentioned firstly create column then add foreign key constraints

$table->foreignId('category_id'); $table->foreign('category_id')->references('id')->on('categories');