I guess you are correct (once again).
Here is what I'm testing on this window (attached for your knowledge).
I'm testing if all the tables are created. So, I'll need to create some different companies to test everything (because of the radiobuttons).
If I try to add a Company with the same name as an existing Company, my application must return me an error. It is doing that, but I'll have to do this test again on next version (that will be released next month) and with the next version after that (that will be released in october/november)...
So, that is the idea of SELECT. I'll test if the application is doing what it needs to do to don't allow Company's name duplication.
But I think other people will test it, so no worries.
Thanks again.