You are viewing a plain text version of this content. The canonical link for it is here.
Posted to issues-all@impala.apache.org by "Quanlong Huang (Jira)" <ji...@apache.org> on 2021/04/12 00:54:00 UTC
[jira] [Updated] (IMPALA-10382) Predicate with coalesce on both
sides of LOJ isn't NULL filtering
[ https://issues.apache.org/jira/browse/IMPALA-10382?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]
Quanlong Huang updated IMPALA-10382:
------------------------------------
Fix Version/s: Impala 4.0
> Predicate with coalesce on both sides of LOJ isn't NULL filtering
> -----------------------------------------------------------------
>
> Key: IMPALA-10382
> URL: https://issues.apache.org/jira/browse/IMPALA-10382
> Project: IMPALA
> Issue Type: Bug
> Components: Frontend
> Reporter: Shant Hovsepian
> Assignee: Xianqing He
> Priority: Critical
> Labels: correctness
> Fix For: Impala 4.0
>
>
> A query like the below will have the outer join simplified to an inner join when the predicate with coalesce isn't always NULL filtering.
> {code:sql}
> select t1.int_col from alltypestiny t1 left outer join alltypesagg t2 on t1.tinyint_col = t2.tinyint_col left outer join alltypes t3 on t1.int_col = t3.int_col where t2.tinyint_col >= coalesce(t1.int_col, t2.int_col);
> {code}
> {noformat}
> functional> set ENABLE_OUTER_JOIN_TO_INNER_TRANSFORMATION=true;
> functional> explain select t1.int_col from alltypestiny t1 left outer join alltypesagg t2 on t1.tinyint_col = t2.tinyint_col left outer join alltypes t3 on t1.int_col = t3.int_col where t2.tinyint_col >= coalesce(t1.int_col, t2.int_col);
> Query: explain select t1.int_col from alltypestiny t1 left outer join alltypesagg t2 on t1.tinyint_col = t2.tinyint_col left outer join alltypes t3 on t1.int_col = t3.int_col where t2.tinyint_col >= coalesce(t1.int_col, t2.int_col)
> +------------------------------------------------------------+
> | Explain String |
> +------------------------------------------------------------+
> | Max Per-Host Resource Reservation: Memory=5.04MB Threads=8 |
> | Per-Host Resource Estimates: Memory=287MB |
> | |
> | PLAN-ROOT SINK |
> | 08:EXCHANGE [UNPARTITIONED] |
> | 04:HASH JOIN [LEFT OUTER JOIN, PARTITIONED] |
> | |--07:EXCHANGE [HASH(t3.int_col)] |
> | | 02:SCAN HDFS [functional.alltypes t3] |
> | 06:EXCHANGE [HASH(t1.int_col)] |
> | 03:HASH JOIN [INNER JOIN, BROADCAST] |
> | |--05:EXCHANGE [BROADCAST] |
> | | 00:SCAN HDFS [functional.alltypestiny t1] |
> | 01:SCAN HDFS [functional.alltypesagg t2] |
> +------------------------------------------------------------+
> Fetched 13 row(s) in 0.02s
> {noformat}
--
This message was sent by Atlassian Jira
(v8.3.4#803005)
---------------------------------------------------------------------
To unsubscribe, e-mail: issues-all-unsubscribe@impala.apache.org
For additional commands, e-mail: issues-all-help@impala.apache.org