This is wrong. It is unsetting the property in the class definition, not the value in this property. And there is no reason to unset the property definition (it will even hurt memory usage)

Setting the properties to ``null`` just after is already unsetting the references to these object.

Remember that ``unset($variable)`` **does not unset** the object. It is only deleting the reference to the object. The garbage collector will then collect the object later in case there is no references left anymore.