Laravel :: Best way to update a foreign key

Question

I have this migration file

Schema::create(\'table_one\', function(Blueprint $table) 
{ 
    $table->increments(\'id\'); 
    $table->string(\'name\');          


        

Answer 1

Drop the foreign key then add it again and run migrate.

public function up()
{
    Schema::table('table_one', function (Blueprint $table) {
        $table->dropForeign(['table_two_id']);

        $table->foreign('table_two_id')
            ->references('id')
            ->on('table_two')
            ->onDelete('cascade');
    });
}

Answer 2

1. composer require doctrine/dbal
2. In your migration file, do this:

    Schema::table('table_one', function (Blueprint $table) {
        $table->foreignId('table_two_id')
              ->change()
              ->constrained('table_two')
              ->onDelete('cascade');
    });

3. php artisan migrate

Answer 3

Christopher K. is right, at the Laravel docs says:

To drop a foreign key, you may use the dropForeign method. Foreign key constraints use the same naming convention as indexes. So, we will concatenate the table name and the columns in the constraint then suffix the name with "_foreign":

$table->dropForeign('posts_user_id_foreign'); 

Or, you may pass an array value which will automatically use the conventional constraint name when dropping:

$table->dropForeign(['user_id']);

https://laravel.com/docs/5.7/migrations#foreign-key-constraints

Answer 4

How to do via Controller

1- Set a Rought:
Route::get('foreignkeyforimg', "foreignkey@index"); 2- Create controller With Foreignkey Name.
3- Foreignkey Controller with extend from Migration class.
4- Go to database and delete old primary key manually from the table

namespace App\Http\Controllers;

use Illuminate\Http\Request;
use Illuminate\Support\Facades\DB;
use Illuminate\Support\Facades\Validator;
use Illuminate\Support\Facades\Schema;
use Illuminate\Database\Migrations\Migration;
use Illuminate\Database\Schema\Blueprint;

class Foreignkey extends Migration
{
    function index(){

        Schema::table('images', function (Blueprint $table) {


            $table->foreign('sub_cat_id')
               ->references('id')
                ->on('subcategories')
                ->onDelete('cascade');
        });
    }
}