Key-Value storage is a very simplistic, but very powerful model. Use this behavior to expand your Yii 2 model without changing the structure.

Data can be queried and saved with "virtual attributes". These are stored serialized in a configured table column.

The preferred way to install this extension is through composer.

Either run

php composer.phar require --prefer-dist cakebake/yii2-scalable-behavior "*"

or add

"cakebake/yii2-scalable-behavior": "*"

to the require section of your composer.json file.

Create a column in your desired table. It is recommended to use the type "text" or "longtext" in order to save as much data as possible.

Once the extension is installed, simply use it in your model by adding:

    use cakebake\behaviors\ScalableBehavior;

    public function behaviors()
    {
        return [
            ...
            'scaleable' => [
                'class' => ScalableBehavior::className(),
                'scalableAttribute' => 'value', // The owner object's attribute / the column of the corresponding table, which are used as storage for the virtual attributes
                'virtualAttributes' => ['about_me', 'birthday'] // Definition of virtual attributes that are added to the owner object
            ],
            ...
        ];
    }

Now we can proceed similarly with the virtual attributes like normal.

    public function rules()
    {
        return [
            ['about_me', 'required'],
            ['about_me', 'string'],
            ['birthday', 'string', 'max' => 60],
        ];
    }

This technique should be used only for metadata. Improper use may change the application performance negatively.