Use $table->foreignIdFor(Model::class) in migrations to create foreign key columns that automatically match the model's primary key type and name.
Hardcoding foreign key column names like $table->unsignedBigInteger('user_id') can lead to type mismatches if the parent model changes primary key types (e.g. from integer to UUID).
foreignIdFor() infers column names and types directly from the target model class.
Basic Usage in Migrations
use App\Models\Company;
use App\Models\User;
use Illuminate\Database\Migrations\Migration;
use Illuminate\Database\Schema\Blueprint;
use Illuminate\Support\Facades\Schema;
return new class extends Migration
{
public function up(): void
{
Schema::create('projects', function (Blueprint $table) {
$table->id();
// Automatically generates 'user_id' matching User's primary key type
$table->foreignIdFor(User::class)->constrained()->cascadeOnDelete();
// Custom column name if needed
$table->foreignIdFor(Company::class, 'client_company_id')->nullable()->constrained('companies');
$table->timestamps();
});
}
};Summary
- Automatically derives column names (
user_id) from model classes. - Chains with
constrained(),nullOnDelete(), andcascadeOnDelete(). - Refactor-safe when changing model classes or database constraints.
Related Tips
View all tips →Use Database Expressions for Dynamic Migration Defaults
Pass an Expression instance to Laravel's migration default() method to define raw SQL functions, dynamic timestamps, and calculated defaults directly in your database schema.
Index Dynamic JSON Attributes with Generated Virtual Columns
Use virtualAs() and storedAs() in migrations to create generated database columns for high-speed indexing on JSON attributes.