[ https://issues.apache.org/jira/browse/PIG-3368?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]
Daniel Dai updated PIG-3368: ---------------------------- Fix Version/s: (was: 0.14.0) 0.15.0 > doc pig flatten operator applied to empty vs null bag > ----------------------------------------------------- > > Key: PIG-3368 > URL: https://issues.apache.org/jira/browse/PIG-3368 > Project: Pig > Issue Type: Improvement > Components: documentation > Reporter: Andy Schlaikjer > Assignee: Aniket Mokashi > Fix For: 0.15.0 > > > [Pig docs|http://pig.apache.org/docs/r0.11.0/basic.html#flatten] state that > FLATTEN(field_of_type_bag) may generate a cross-product in the case when an > additional field is projected, e.g.: > y = FOREACH x GENERATE f1, FLATTEN(fbag) as f2; > Additionally, for records in x for which fbag is empty (not null), no output > record is generated. > What is expected behavior when fbag is null? > Some users might expect similar behavior, but FLATTEN actually passes through > the null, resulting in an output record (f1, f2) where f2 is null. > It would be useful to update FLATTEN docs to mention this. > http://svn.apache.org/viewvc/pig/trunk/src/docs/src/documentation/content/xdocs/basic.xml?view=markup#l5051 > I'm guessing these are the relevant bits which affect this behavior: > http://svn.apache.org/viewvc/pig/trunk/src/org/apache/pig/backend/hadoop/executionengine/physicalLayer/relationalOperators/POForEach.java?view=markup#l440 > http://svn.apache.org/viewvc/pig/trunk/src/org/apache/pig/backend/hadoop/executionengine/physicalLayer/relationalOperators/POForEach.java?view=markup#l468 -- This message was sent by Atlassian JIRA (v6.3.4#6332)