Okay lets say I have a basic demographic content type (Client) that I am saving as a node.
I need to make a key for an external database that we occasionally need to work with.
I want Drupal to take the fragments of three fields being collected in the Client content type and join them into a single field to be saved within the Client content type. Ideally this should be done when I create a new (Client) node.
The new field should contain the following First 3 letters of firstname First 3 letters of lastname and last 4 digits of Social Security Number.
For example
firstname: John
lastname: Doe
SSN: 123-45-6789A new field should be created, let’s call it fk_database. Using the example above the field >created would be -> johdoe6789
Can this be done via Rules module, or should I approach this in a different way? If I need to do this via a PHP script where exactly should that be added in the Drupal structure?