Is it true that indexing a main domain, www.example.com is much quicker than a subdomain, example.mycompany.com ? I have heard of Google indexing a site in one day or two, but what about subdomain? Does it take much longer if not NEVER? Any comments will be very much appreciated.
Google give more preference to the top level domain name but if your subdomain has enough backlinking it can be indexed fast.
No, eventhough google prioritizes the main site. It will indexed your remaining subpages after indexing your main page.