title: possibility to create a group for user php
body: <p>What's the best way for add possibility for users can create a group?  </p>
  
  <p>My problem is for SQL table, i don't know how i can do it easily.</p>
  
  <p><em>i have created a simple diagram :</em></p>
  
  <p><img src="https://i.stack.imgur.com/NiSs8.png" alt="enter image description here"></p>
  
  <p>But I think, I need something because if a user want to join or create a specific group how I can do that?</p>