Hi, We are finalizing a feature that would solve your problems, something like ROW_NUMBER in some SQL dialect, we call it RANK. This operator will add a unique consecutive row number to each tuple in the relationship. Then you will be able to join the two relationships on the rank field.
For the moment being, however, I think there is no easy way to achieve what you want to do. Cheers, -- Gianmarco On Tue, Aug 14, 2012 at 11:55 AM, Lauren Blau < [email protected]> wrote: > I want to match up tuples from 2 relations. For each key, the 2 relations > will always have the same number of tuples and match by position (the first > tuple in each are a match, the second tuple in each, etc). > > so if I have > relation1 = 5,9,7 > relation2 = z,a,d > > I want to end up with > > relation3 = (5,z),(9,a),(7,d) > > I figure I need a way to generate a matching key on the ordered tuples of > the relations and then do a cogroup. But I'm stuck on generating the key. > Since adding a field is a project, I assume this has to be done as part of > a foreach loop. But I'm not sure how I can maintain the order while adding > a field to each tuple. > > ideas? > Thanks, > lauren >
