title: Access, allow mutli non - predefined value
body: <p><strong>Issue :</strong> I created a table on Access and I am trying to add a field in which the user can enter multiple values, but which are not predefined in a list.
  Those values must all respect a certain format though.</p>
  
  <p><strong>My current solution :</strong></p>
  
  <p><a href="https://i.stack.imgur.com/HOwbc.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/HOwbc.png" alt="enter image description here"></a>
  <a href="https://i.stack.imgur.com/vJXvV.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/vJXvV.png" alt="enter image description here"></a></p>
  
  <p>I created a combo box with a validation rule.
  I specified also Row Source Type as Value List and didn't put any value in the list so that the user can enter them by himself and will only be able to use them if they follow the validation rule.</p>
  
  <p>As you can see in the picture above, the user could add any values to the list, but the value 88 could not be used since it doesn't obey the validation rule.</p>
  
  <p>Unfortunately, this is not a nice solution since all values added by the user will sum up and the list will get bigger and bigger with time...do you know a better way ?</p>