> ## Documentation Index
> Fetch the complete documentation index at: https://docs.lunarphp.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Tags

Tags provide a way to relate otherwise unrelated models, enabling features like dynamic collections.

## Overview

Tags provide a way to relate otherwise unrelated models in the system. They also impact other features such as Dynamic Collections.

For example, two products "Blue T-Shirt" and "Blue Shoes" are unrelated by nature, but adding a `BLUE` tag to each product allows a Dynamic Collection to include any products with that tag.

```php theme={null}
Lunar\Models\Tag
```

### Fields

| Field        | Type        | Description   |
| :----------- | :---------- | :------------ |
| `id`         | `id`        | Primary key   |
| `value`      | `string`    | The tag value |
| `created_at` | `timestamp` |               |
| `updated_at` | `timestamp` |               |

<Tip>
  Tags are automatically converted to uppercase when saved via the `syncTags` method.
</Tip>

## Enabling tags

To enable tagging on a model, add the `HasTags` trait:

```php theme={null}
<?php

namespace App\Models;

use Illuminate\Database\Eloquent\Model;
use Lunar\Base\Traits\HasTags;

class SomethingWithTags extends Model
{
    use HasTags;

    // ...
}
```

Tags can then be attached using `syncTags`:

```php theme={null}
use Lunar\Models\Tag;

$tags = collect([
    Tag::firstOrCreate(['value' => 'TAG ONE']),
    Tag::firstOrCreate(['value' => 'TAG TWO']),
    Tag::firstOrCreate(['value' => 'TAG THREE']),
]);

$model = SomethingWithTags::first();

$model->syncTags($tags);
```

The `syncTags` method accepts a collection of `Tag` models. Tags are automatically converted to uppercase when saved. The sync process runs via a queued job (`Lunar\Jobs\SyncTags`), so changes may not be reflected immediately if using an asynchronous queue driver.