You are viewing a plain text version of this content. The canonical link for it is here.
Posted to issues@spark.apache.org by "Reynold Xin (JIRA)" <ji...@apache.org> on 2016/07/29 22:05:20 UTC
[jira] [Updated] (SPARK-16804) Correlated subqueries containing
LIMIT return incorrect results
[ https://issues.apache.org/jira/browse/SPARK-16804?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]
Reynold Xin updated SPARK-16804:
--------------------------------
Description:
Correlated subqueries with LIMIT could return incorrect results. The rule ResolveSubquery in the Analysis phase moves correlated predicates to a join predicates and neglect the semantic of the LIMIT.
Example:
{noformat}
Seq(1, 2).toDF("c1").createOrReplaceTempView("t1")
Seq(1, 2).toDF("c2").createOrReplaceTempView("t2")
sql("select c1 from t1 where exists (select 1 from t2 where t1.c1=t2.c2 LIMIT 1)").show
+---+
| c1|
+---+
| 1|
+---+
{noformat}
The correct result contains both rows from T1.
was:
Correlated subqueries with LIMIT could return incorrect results. The rule ResolveSubquery in the Analysis phase moves correlated predicates to a join predicates and neglect the semantic of the LIMIT.
Example:
Seq(1, 2).toDF("c1").createOrReplaceTempView("t1")
Seq(1, 2).toDF("c2").createOrReplaceTempView("t2")
sql("select c1 from t1 where exists (select 1 from t2 where t1.c1=t2.c2 LIMIT 1)").show
+---+
| c1|
+---+
| 1|
+---+
The correct result contains both rows from T1.
> Correlated subqueries containing LIMIT return incorrect results
> ---------------------------------------------------------------
>
> Key: SPARK-16804
> URL: https://issues.apache.org/jira/browse/SPARK-16804
> Project: Spark
> Issue Type: Bug
> Components: SQL
> Affects Versions: 2.0.0
> Reporter: Nattavut Sutyanyong
> Original Estimate: 72h
> Remaining Estimate: 72h
>
> Correlated subqueries with LIMIT could return incorrect results. The rule ResolveSubquery in the Analysis phase moves correlated predicates to a join predicates and neglect the semantic of the LIMIT.
> Example:
> {noformat}
> Seq(1, 2).toDF("c1").createOrReplaceTempView("t1")
> Seq(1, 2).toDF("c2").createOrReplaceTempView("t2")
> sql("select c1 from t1 where exists (select 1 from t2 where t1.c1=t2.c2 LIMIT 1)").show
> +---+
> | c1|
> +---+
> | 1|
> +---+
> {noformat}
> The correct result contains both rows from T1.
--
This message was sent by Atlassian JIRA
(v6.3.4#6332)
---------------------------------------------------------------------
To unsubscribe, e-mail: issues-unsubscribe@spark.apache.org
For additional commands, e-mail: issues-help@spark.apache.org