Yes, the first glance at your question suggested that you did not do enough own research to understand the data philosophy of Visio.
Reading a little bit more carefully your post, revealled that you stepped into one of Visio's problems:
the capability to edit the shapes data in a table form in Visio itself.
There could be solutions to overcome this lack, but I wouldn't know of any comfortable solution for this problem.
Nikolay has even written a brilliant solution to synchronize external data with the shapes data (
http://unmanagedvisio.com/products/backsync-backward-visio-data-synchronization/),
but it is still not as comfortable as what you are asking for.
I'm not saying that it is not feasable, but you'll have to invest a lot of work to get your wish working.
Regards,
Yacine