CommonJoinOperator optimize the case that 1:1 join
--------------------------------------------------
Key: HIVE-1783
URL: https://issues.apache.org/jira/browse/HIVE-1783
Project: Hive
Issue Type: Improvement
Reporter: Siying Dong
Assignee: Siying Dong
Priority: Minor
CommonJoinOperator.genObject() is expensive. It does a recursive and keeps lots
of states because it has to:
1. handle null cases for outer joins
2. handle the case of duplicated keys from one join party
We can do a minor optimization to detect a 1:1 join (which is quite common)
before calling CommonJoinOperator.genObject() and forward columns in a simple
for-loop if we are sure neither of 1 or 2 will happen.
--
This message is automatically generated by JIRA.
-
You can reply to this email to add a comment to the issue online.
