[jira] [Created] (HIVE-20285) Outer joins are underestimated

["Zoltan Haindrich (JIRA)" <ji...@apache.org>]

Zoltan Haindrich created HIVE-20285:
---------------------------------------

             Summary: Outer joins are underestimated
                 Key: HIVE-20285
                 URL: https://issues.apache.org/jira/browse/HIVE-20285
             Project: Hive
          Issue Type: Bug
          Components: Statistics
            Reporter: Zoltan Haindrich


It seems {{X LEFT OUTER JOIN Y}} is sometimes estimated to have fewer rows than {{X}}.

in ql/src/test/results/clientpositive/llap/auto_join29.q.out:
{code}
 SELECT * FROM src src1 LEFT OUTER JOIN src src2 ON (src1.key = src2.key AND src1.key < 10 AND src2.key 
> 10) LEFT OUTER JOIN src src3 ON (src2.key = src3.key AND src3.key < 10) SORT BY src1.key, src1.value, 
src2.key, src2.value, src3.key, src3.value
{code}





--
This message was sent by Atlassian JIRA
(v7.6.3#76005)