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Posted to issues@spark.apache.org by "Apache Spark (JIRA)" <ji...@apache.org> on 2015/12/02 03:29:11 UTC
[jira] [Commented] (SPARK-12085) The join condition hidden in DNF
can't be pushed down to join operator
[ https://issues.apache.org/jira/browse/SPARK-12085?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15035146#comment-15035146 ]
Apache Spark commented on SPARK-12085:
--------------------------------------
User 'flyson' has created a pull request for this issue:
https://github.com/apache/spark/pull/10087
> The join condition hidden in DNF can't be pushed down to join operator
> -----------------------------------------------------------------------
>
> Key: SPARK-12085
> URL: https://issues.apache.org/jira/browse/SPARK-12085
> Project: Spark
> Issue Type: Improvement
> Components: SQL
> Reporter: Min Qiu
>
> TPC-H Q19:
> {quote}
> SELECT sum(l_extendedprice * (1 - l_discount)) AS revenue FROM part join lineitem
> WHERE ({color: red}p_partkey = l_partkey {color}
> AND p_brand = 'Brand#12'
> AND p_container IN ('SM CASE', 'SM BOX', 'SM PACK', 'SM PKG')
> AND l_quantity >= 1 AND l_quantity <= 1 + 10
> AND p_size BETWEEN 1 AND 5
> AND l_shipmode IN ('AIR', 'AIR REG')
> AND l_shipinstruct = 'DELIVER IN PERSON')
> OR ({color: red}p_partkey = l_partkey{color}
> AND p_brand = 'Brand#23'
> AND p_container IN ('MED BAG', 'MED BOX', 'MED PKG', 'MED PACK')
> AND l_quantity >= 10 AND l_quantity <= 10 + 10
> AND p_size BETWEEN 1 AND 10
> AND l_shipmode IN ('AIR', 'AIR REG') AND l_shipinstruct = 'DELIVER IN PERSON')
> OR ({color: red}p_partkey = l_partkey{color}
> AND p_brand = 'Brand#34'
> AND p_container IN ('LG CASE', 'LG BOX', 'LG PACK', 'LG PKG')
> AND l_quantity >= 20 AND l_quantity <= 20 + 10
> AND p_size BETWEEN 1 AND 15
> AND l_shipmode IN ('AIR', 'AIR REG') AND l_shipinstruct = 'DELIVER IN PERSON')
> {quote}
> The equality condition {color:red} p_partkey = l_partkey{color} matches the join relations but it cannot be recogized by optimizer because it's hidden in a disjunctive normal form. As a result the entire where clause will be in a filter operator on top of the join operator where the join condition would be "None" in the optimized plan. Finally the query planner will apply a prohibitive expensive cartesian product on the physical plan which causes OOM exception or very bad performance.
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