[ https://issues.apache.org/jira/browse/IMPALA-9162?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]
Aman Sinha resolved IMPALA-9162. -------------------------------- Fix Version/s: Impala 3.4.0 Resolution: Fixed > Incorrect redundant predicate applied to outer join > --------------------------------------------------- > > Key: IMPALA-9162 > URL: https://issues.apache.org/jira/browse/IMPALA-9162 > Project: IMPALA > Issue Type: Bug > Components: Frontend > Reporter: Aman Sinha > Assignee: Aman Sinha > Priority: Major > Fix For: Impala 3.4.0 > > Attachments: create.sql.txt > > > Run the attached create.sql script to create the tables and view. The > following query shows an incorrect redundant predicate applied to the outer > join. This seems another variant of past issues such as IMPALA-7957 and > IMPALA-8386. > {noformat} > // Has a redundant predicate as 'Other predicates' on Outer Join > Query: explain select x.* from (select v1.c3, v1.max_c3 from v.t2 left join > v.v1 on t2.c2=v1.c3) as x > > > 06:HASH JOIN [RIGHT OUTER JOIN, PARTITIONED] > hash predicates: c3 = t2.c2 > other predicates: c3 = max(c3) . <-- WRONG > runtime filters: RF000 <- t2.c2 > row-size=20B cardinality=397 > > --13:EXCHANGE [HASH(t2.c2)] > > 00:SCAN HDFS [v.t2] > HDFS partitions=1/1 files=1 size=639B > row-size=4B cardinality=397 > > > 12:EXCHANGE [HASH(c3)] > > > > 05:HASH JOIN [INNER JOIN, BROADCAST] > > hash predicates: c3 = max(c3) > > runtime filters: RF002 <- max(c3) > > row-size=16B cardinality=207 > {noformat} > > By comparison, the following query which does not have the v1.max_c3 column > in the SELECT list produces the correct plan: > {noformat} > // Does not have the redundant predicate > Query: explain select x.* from (select v1.c3 from v.t2 left join v.v1 on > t2.c2=v1.c3) as x > 06:HASH JOIN [RIGHT OUTER JOIN, PARTITIONED] > hash predicates: c3 = t2.c2 > runtime filters: RF000 <- t2.c2 > row-size=20B cardinality=397 > --13:EXCHANGE [HASH(t2.c2)] > 00:SCAN HDFS [v.t2] > HDFS partitions=1/1 files=1 size=639B > row-size=4B cardinality=397 > 12:EXCHANGE [HASH(c3)] > 05:HASH JOIN [INNER JOIN, BROADCAST] > hash predicates: c3 = max(c3) > runtime filters: RF002 <- max(c3) > row-size=16B cardinality=207 > {noformat} > Due the redundant predicate, the first query produces wrong results. -- This message was sent by Atlassian Jira (v8.3.4#803005) --------------------------------------------------------------------- To unsubscribe, e-mail: issues-all-unsubscr...@impala.apache.org For additional commands, e-mail: issues-all-h...@impala.apache.org