I cant drop a forener key in laravel my migration

hello , I created this file with migration -

return new class extends Migration
{
    /**
     * Run the migrations.
     */
    public function up(): void
    {
        Schema::table('products', function (Blueprint $table) {
            $table->foreignId('company_id')->nullable()->references('id')->on('company');
        });
    }

    /**
     * Reverse the migrations.
     */
    public function down(): void
    {
        Schema::create('products', function (Blueprint $table) {
            $table->dropForeign('company_id_foreign');
        });
        Schema::dropIfExists('products');
    }
};

now I created other migration and I want to drop , the company_id column and the forener key .

return new class extends Migration
{
    /**
     * Run the migrations.
     */
    public function up(): void
    {
        Schema::table('products', function (Blueprint $table) {
            $$table->dropForeign('company_id');
        });
    }

    /**
     * Reverse the migrations.
     */
    public function down(): void
    {
        Schema::create('products', function (Blueprint $table) {
            $table->dropForeign('company_id_foreign');
        });
        Schema::dropIfExists('products');
    }
};

I tryed to use drop forenerId, dropColumn . but all of then I cant drop the the forener key , it gives this error -

  SQLSTATE[42000]: Syntax error or access violation: 1091 Can't DROP 'company_id'; check that column/key exists (Connection: mysql, SQL: alter table `products` drop foreign key `company_id`)

  at vendor/laravel/framework/src/Illuminate/Database/Connection.php:822
    818▕                     $this->getName(), $query, $this->prepareBindings($bindings), $e
    819▕                 );
    820▕             }
    821▕ 
  ➜ 822▕             throw new QueryException(
    823▕                 $this->getName(), $query, $this->prepareBindings($bindings), $e
    824▕             );
    825▕         }
    826▕     }

      +9 vendor frames

LaryAI

2 years ago

Best Answer

Level 58

It looks like you're trying to drop a foreign key in your migration, but you're encountering an error because the syntax for dropping a foreign key is incorrect. When dropping a foreign key, you need to specify the foreign key constraint name, not the column name. Laravel typically creates a constraint name based on the table name and the foreign key column name.

Here's how you can correctly drop the foreign key and the column:

return new class extends Migration
{
    /**
     * Run the migrations.
     */
    public function up(): void
    {
        Schema::table('products', function (Blueprint $table) {
            // Drop the foreign key constraint
            $table->dropForeign(['company_id']);
            // Now you can safely drop the column
            $table->dropColumn('company_id');
        });
    }

    /**
     * Reverse the migrations.
     */
    public function down(): void
    {
        Schema::table('products', function (Blueprint $table) {
            // Add the column back
            $table->foreignId('company_id')->nullable();
            // Recreate the foreign key constraint
            $table->foreign('company_id')->references('id')->on('companies');
        });
    }
};

Please note the following:

The dropForeign method takes an array as an argument, which should contain the name of the column you are targeting.
You should drop the foreign key before dropping the column itself.
In the down method, you should recreate the column and the foreign key constraint to reverse the migration correctly. Make sure to use the correct table name in the on method (it should be 'companies' if your table is named 'companies').
Ensure that the down method is the exact opposite of the up method to maintain the integrity of your migrations.

If you follow these steps, you should be able to drop the foreign key and the column without any errors.

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