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From Alan Gates <ga...@yahoo-inc.com>
Subject Re: Confused about COGroup semantic
Date Thu, 15 May 2008 23:51:43 GMT
There really isn't any meaning to cogrouping with one field on one 
relation and two fields on another.  Given our definition of tuple, 
there will never be any tuples that match.  I believe Santhosh has 
changed this to be a syntax error.

Alan.

pi song wrote:
> Normally we do COGroup like this:-
>
> X = COGroup A By $0, B By $0 ;
>
> This first column of the output will be data atom.
>
> But if we do:-
>
> X = COGroup A By $0, B By $0, $1 ;
>
> What is the the first column then? I assume the B grouping will be wrapped
> to tuple and treated as atom. Am I right?
>
> Pi
>
>   

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