Help on merging without a common variable

On Thu, Aug 2, 2012 at 4:52 PM, Ayyappa Chaturvedula

Michael,
Thank  you for this , it worked.  I was thinking "by" is a required argument
in merge function.

Well, it is "required" in a strict sense, but it has a default value
(defaulting to the shared names) so _you_ don't have to specify it.

Best,
Michael

Regards,
Ayyappa