Database Seeding

Database seeding is a simple way to add data into your database. It is especially useful during development where you need to populate the database with sample data that you can develop against, but it is not limited to that. Seeds can contain static data that you don’t want to include in a migration, like countries, or geo-coding tables, event or setting information, and more.

Database seeds are simple classes that must have a run() method, and extend CodeIgniter\Database\Seeder. Within the run() the class can create any form of data that it needs to. It has access to the database connection and the forge through $this->db and $this->forge, respectively. Seed files must be stored within the app/Database/Seeds directory. The name of the file must match the name of the class.

<?php

namespace App\Database\Seeds;

use CodeIgniter\Database\Seeder;

class SimpleSeeder extends Seeder
{
        public function run()
        {
                $data = [
                        'username' => 'darth',
                        'email'    => 'darth@theempire.com'
                ];

                // Simple Queries
                $this->db->query("INSERT INTO users (username, email) VALUES(:username:, :email:)", $data);

                // Using Query Builder
                $this->db->table('users')->insert($data);
        }
}

Nesting Seeders

Seeders can call other seeders, with the call() method. This allows you to easily organize a central seeder, but organize the tasks into separate seeder files:

<?php

namespace App\Database\Seeds;

use CodeIgniter\Database\Seeder;

class TestSeeder extends Seeder
{
        public function run()
        {
                $this->call('UserSeeder');
                $this->call('CountrySeeder');
                $this->call('JobSeeder');
        }
}

You can also use a fully-qualified class name in the call() method, allowing you to keep your seeders anywhere the autoloader can find them. This is great for more modular code bases:

public function run()
{
        $this->call('UserSeeder');
        $this->call('My\Database\Seeds\CountrySeeder');
}

Using Faker

If you want to automate the generation of seed data, you can use the Faker library.

To install Faker into your project:

> composer require --dev fakerphp/faker

After installation, an instance of Faker\Generator is available in the main Seeder class and is accessible by all child seeders. You must use the static method faker() to access the instance.

<?php

namespace App\Database\Seeds;

use CodeIgniter\Database\Seeder;

class UserSeeder extends Seeder
{
        public function run()
        {
                $model = model('UserModel');

                $model->insert([
                        'email'      => static::faker()->email,
                        'ip_address' => static::faker()->ipv4,
                ]);
        }
}

Using Seeders

You can grab a copy of the main seeder through the database config class:

$seeder = \Config\Database::seeder();
$seeder->call('TestSeeder');

Command Line Seeding

You can also seed data from the command line, as part of the Migrations CLI tools, if you don’t want to create a dedicated controller:

> php spark db:seed TestSeeder

Creating Seed Files

Using the command line, you can easily generate seed files.

// This command will create a UserSeeder seed file
// located at app/Database/Seeds/ directory.
> php spark make:seeder UserSeeder

You can supply the root namespace where the seed file will be stored by supplying the -n option:

> php spark make:seeder MySeeder -n Acme\Blog

If Acme\Blog is mapped to app/Blog directory, then this command will save the seed file to app/Blog/Database/Seeds/.

Supplying the --force option will overwrite existing files in destination.