>> I'll post a patch that makes the second option official and changes all the examples of the first to return null with STATUS_OK (this is what happens with the constant null currently).
I am +1 for this. On Fri, Nov 8, 2013 at 10:16 PM, Mark Wagner <[email protected]>wrote: > Hi Devs, > > While discussing the Pig on Tez project today, we were unable to reach > a conclusion on what the semantics of what POStatus.STATUS_NULL are > and would like to ask those who remember the history of Pig to chime > in. The two interpretations are: > > 1. POStatus.STATUS_NULL indicates that the pulled output IS null. This > is used in some places like EqualToExpr. > > 2. POStatus.STATUS_NULL indicates that the pull did not produce any > output. This is backed up by it's usage in POPackage for flattening an > empty bag, and PigGenericMapBase where pulls on the operator pipeline > that result in STATUS_NULL are discarded. > > If nobody has any concrete documentation or explanation for the > discrepancy, I'll post a patch that makes the second option official > and changes all the examples of the first to return null with > STATUS_OK (this is what happens with the constant null currently). > > Thanks, > Mark >
