[ 
https://issues.apache.org/jira/browse/CALCITE-2894?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
 ]

Ruben Quesada Lopez reassigned CALCITE-2894:
--------------------------------------------

    Assignee: Ruben Quesada Lopez

> NullPointerException thrown by RelMdPercentageOriginalRows when explaining 
> plan with all attributes
> ---------------------------------------------------------------------------------------------------
>
>                 Key: CALCITE-2894
>                 URL: https://issues.apache.org/jira/browse/CALCITE-2894
>             Project: Calcite
>          Issue Type: Bug
>    Affects Versions: 1.18.0
>            Reporter: Ruben Quesada Lopez
>            Assignee: Ruben Quesada Lopez
>            Priority: Minor
>
> {{RelMdPercentageOriginalRows}} methods use several times {{double}} 
> variables to store the result of {{getPercentageOriginalRows}}. However, this 
> method returns an object {{Double}}, as 
> {{RelMetadataQuery#getPercentageOriginalRows}} javadoc says: "return 
> estimated percentage (between 0.0 and 1.0), *or null if no reliable estimate 
> can be determined*". 
> Therefore, {{null}} can (and will) be returned in some cases, leading to 
> NullPointerException.
> In my case, I arrived to the situation by explaining a plan (including all 
> attributes) that contained a SemiJoin, with an Union inside, with a Correlate 
> inside:
> {code:java}
>   @Test public void testExplainAllAttributesSemiJoinUnionCorrelate() {
>     CalciteAssert.that()
>             .with(CalciteConnectionProperty.LEX, Lex.JAVA)
>             .with(CalciteConnectionProperty.FORCE_DECORRELATE, false)
>             .withSchema("s", new ReflectiveSchema(new JdbcTest.HrSchema()))
>             .query(
>                     "select deptno, name from depts where deptno in (\n"
>                             + " select e.deptno from emps e where exists 
> (select 1 from depts d where d.deptno=e.deptno)\n"
>                             + " union select e.deptno from emps e where 
> e.salary > 10000) ")
>             .explainMatches("including all attributes ",
>                     CalciteAssert.checkResultContains("EnumerableSemiJoin"));
>   }
> {code}



--
This message was sent by Atlassian JIRA
(v7.6.3#76005)

Reply via email to