Revision 1297919

HIVE-2827 [jira] Implement nullsafe equi-join
(Navis Ryu via Carl Steinbach)

Summary:
DPAL-873 Implement nullsafe equi-join

was part of HIVE-2810, but separated because it affected more classes than
expected.

SELECT * FROM a JOIN b ON a.key <=> b.key

Test Plan: EMPTY

Reviewers: JIRA, cwsteinbach

Reviewed By: cwsteinbach

Differential Revision: https://reviews.facebook.net/D1971