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Hive, mail # dev - Review Request 19165: HIVE-6643: Add a check for cross products in plans and output a warning


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Re: Review Request 19165: HIVE-6643: Add a check for cross products in plans and output a warning
Harish Butani 2014-03-17, 00:42

This is an automatically generated e-mail. To reply, visit:
https://reviews.apache.org/r/19165/

(Updated March 17, 2014, 12:42 a.m.)
Review request for hive and Gunther Hagleitner.
Changes

changes suggested by gunther
Bugs: HIVE-6643
    https://issues.apache.org/jira/browse/HIVE-6643
Repository: hive-git
Description

Now that we support old style join syntax, it is easy to write queries that generate a plan with a cross product.
For e.g. say you have A join B join C join D on A.x = B.x and A.y = D.y and C.z = D.z
So the JoinTree is:
A — B
__ D — C
Since we don't reorder join graphs, we will end up with a cross product between (A join B) and C
Diffs (updated)

  common/src/java/org/apache/hadoop/hive/conf/HiveConf.java 56d68f5
  conf/hive-default.xml.template 906ea8c
  itests/qtest/pom.xml f8b81a2
  ql/src/java/org/apache/hadoop/hive/ql/optimizer/physical/CrossProductCheck.java PRE-CREATION
  ql/src/java/org/apache/hadoop/hive/ql/optimizer/physical/PhysicalOptimizer.java d593d08
  ql/src/java/org/apache/hadoop/hive/ql/parse/TezCompiler.java a5e6cbf
  ql/src/test/queries/clientpositive/cross_product_check_1.q PRE-CREATION
  ql/src/test/queries/clientpositive/cross_product_check_2.q PRE-CREATION
  ql/src/test/results/clientpositive/cross_product_check_1.q.out PRE-CREATION
  ql/src/test/results/clientpositive/cross_product_check_2.q.out PRE-CREATION
  ql/src/test/results/clientpositive/tez/cross_product_check_1.q.out PRE-CREATION
  ql/src/test/results/clientpositive/tez/cross_product_check_2.q.out PRE-CREATION

Diff: https://reviews.apache.org/r/19165/diff/
Testing

added new tests
Thanks,

Harish Butani