Laravel Migration

You are a Laravel database architect. The user wants to create database migrations with foreign keys and indexes to structure their database schema properly.

What to check first

• Run php artisan migrate:status to see existing migrations
• Verify your database connection in .env file (DB_CONNECTION, DB_HOST, DB_DATABASE)
• Check that database/migrations directory exists in your Laravel project root

Steps

1. Generate a new migration file using php artisan make:migration create_users_table --create=users (use --create for new tables or --table for modifications)
2. Open the generated migration file in database/migrations/YYYY_MM_DD_HHMMSS_create_users_table.php
3. In the up() method, define columns with $table->id() for primary keys, then add other columns with appropriate types (string(), integer(), text(), timestamp(), etc.)
4. Add foreign key constraints using $table->foreignId('role_id')->constrained('roles')->onDelete('cascade') which automatically creates the foreign key relationship
5. Add indexes with $table->index(['column_name']) for frequently queried columns or $table->unique(['email']) for unique constraints
6. Define the down() method with $table->dropIfExists('users') to allow rollback
7. Run php artisan migrate to execute the migration and create the table in your database
8. Verify the table structure with php artisan tinker and query \DB::select('describe users')

Code

<?php

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('posts', function (Blueprint $table) {
            $table->id();
            $table->foreignId('user_id')->constrained('users')->onDelete('cascade');
            $table->foreignId('category_id')->constrained('categories')->onDelete('restrict');
            $table->string('title', 255);
            $table->text('content');
            $table->string('slug', 255)->unique();
            $table->enum('status', ['draft', 'published', 'archived'])->default('draft');
            $table->integer('views')->default(0);
            $table->timestamps();
            
            // Indexes for query performance
            $table->index('user_id');
            $table->index('category_id');
            $table->index('slug');
            $table->index('status');
            $table->index(['created_at', 'status']);
        });
    }

    public function down(): void
    {
        Schema::dropIfExists('posts');
    }
};

Pitfalls

• Foreign keys must reference an existing primary key column; if the parent table doesn't exist yet, create

Common Pitfalls

• Treating this skill as a one-shot solution — most workflows need iteration and verification
• Skipping the verification steps — you don't know it worked until you measure
• Applying this skill without understanding the underlying problem — read the related docs first

When NOT to Use This Skill

• When a simpler manual approach would take less than 10 minutes
• On critical production systems without testing in staging first
• When you don't have permission or authorization to make these changes

How to Verify It Worked

• Run the verification steps documented above
• Compare the output against your expected baseline
• Check logs for any warnings or errors — silent failures are the worst kind

Production Considerations

• Test in staging before deploying to production
• Have a rollback plan — every change should be reversible
• Monitor the affected systems for at least 24 hours after the change