title: How to update assignment in auth_assignment table in Yii2 Rbac?
body: <p>I am using RBAC in my yii2 basic application to assign module to users based on their roles.</p>
  
  <p>I store role id and user_id in auth_assignment table.</p>
  
  <p>Now if i change role of user during update. I have to change it also in auth_assignment table. Now I want to delete all entries of that user from auth assignment and add new entries in table.</p>
  
  <p>The problem is that i cannot find any RBAC function to update auth_assignment table data or to delete auth assignment table data.</p>
  
  <p>There is a function in Yii2 Documentation <code>removeAllAssignments()</code> but it truncates the whole table i only want to delete entries for perticular user.</p>
  
  <p>Is there any function available for that?</p>