Laravel load settings from database

IMHO it's a bit over engineered. You can do the same with the helper approach:

function settings($key)
{
    static $settings;

    if(is_null($settings))
    {
        $settings = Cache::remember('settings', 24*60, function() {
            return array_pluck(App\Setting::all()->toArray(), 'value', 'key');
        });
    }

    return (is_array($key)) ? array_only($settings, $key) : $settings[$key];
}

Less cumbersome. No loops. Max 1 DB hit per request. Max 1 Cache hit per request.

Here is an updated answer as of Laravel 5.5.

First, create a migration for your settings table:

Schema::create('settings', function (Blueprint $table) {
    $table->increments('id');
    $table->string('key');
    $table->text('value')->nullable();
    $table->timestamps();
});

Then create a Setting model:

<?php

namespace App;

use Illuminate\Database\Eloquent\Model;

class Setting extends Model
{
    protected $fillable = ['key', 'value'];
}

Now, in AppServiceProvider, add the following to your boot() method:

if (Schema::hasTable('settings')) {
    foreach (Setting::all() as $setting) {
        Config::set('settings.'.$setting->key, $setting->value);
    }
}

This will create config('settings.*') for each setting in your database, where * is the key.

For example, insert/create the following setting:

Setting::create([
    'key' => 'example',
    'value' => 'Hello World',
]);

Now you can access config('settings.example'), which will give you Hello World.

Updating settings is as simple as doing:

Setting::where('key', 'example')->update([
    'value' => 'My New Value',
]);