Hi Aaron and Alex,
Thanks so much for your response. Excuse my limited understanding, did Aaron answered the 1:1 relationship question and Alex's answer dealt with the “same name” question? I have got some clues from your answers.
Can you explain more detail of the solution for the requirements? Do I need to code plugin using such as Unique Attribute to do them?
I’ll rewrite the question and post it in the same forum. Please kindly review it and offer some suggestion.