Saving return values of function value to Database

Yii 2.0 General Discussions
1

I have created a function in my model PatientDetail.php.

This function is working well and returning the desired value, but I am not able to save the same in database.




public function getRoomCategory(){

     $model = \app\models\RoomCategory::find('id')

     ->innerJoin('room_charges','room_charges.room_category=room_category.id')

     ->innerjoin('patient_detail', 'room_charges.id = patient_detail.bed_type')               

     ->Where(['patient_detail.id'=> $this->id])->one();


     return $model;


   }

I have a field/Column in the model as ‘room_category’ and I want to save the return value of the function getRoomCategory in the Database.

I have tried to create the function with the same name like getroom_category(){}, but then I am not getting any value in the form field in my _form.php

What is the best way to save the calculated value to the database? Thank for your valuable guidance.