I have 3 URLS that serve the same data:
www.example.com/product/foowww.example.com/product/foo?id=1www.example.com?product=foo
For Google's sake I want the URL www.example.com/product/foo to be the canonical one.
However, I have my code setup so all 3 of those pages are served from the same code so if I add in <link rel='canonical' href='http://www.example.com/product/foo' /> to my code it will be applied to all 3 pages, including the one http://www.example.com/product/foo.
Is there any issue with doing this or does having a circular canonical not cause any issues?