[
https://issues.apache.org/jira/browse/CALCITE-1862?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16396908#comment-16396908
]
zhen wang commented on CALCITE-1862:
------------------------------------
{code}
before transform:
EnumerableFilter(condition=[IS NULL(null)])
EnumerableProject(subset=[rel#44:Subset#5.ENUMERABLE.[]], EMPNO=[$0])
EnumerableFilter(subset=[rel#142:Subset#7.ENUMERABLE.[]], condition=[AND(IS
NULL(null), IS NULL(null))])
EnumerableTableScan(subset=[rel#24:Subset#0.ENUMERABLE.[0]],
table=[[scott, EMP]])
after transform:
EnumerableProject(EMPNO=[$0])
EnumerableFilter(condition=[IS NULL(null)])
EnumerableFilter(subset=[rel#240:Subset#16.ENUMERABLE.[]], condition=[IS
NULL(null)])
EnumerableFilter(subset=[rel#234:Subset#15.ENUMERABLE.[]], condition=[IS
NULL(null)])
EnumerableFilter(subset=[rel#88:Subset#6.ENUMERABLE.[]], condition=[IS
NULL(null)])
EnumerableTableScan(subset=[rel#24:Subset#0.ENUMERABLE.[0]],
table=[[scott, EMP]])
{code}
This occurred when the `Project` relation is a RelSubset, the match process
didn't choose the best of the Project equivalent RelSubset, but instead chose
not optimized one. causing the rule to be fired again and again, causing stack
overflow.
> StackOverflowException in RelMdUtil.estimateFilteredRows
> --------------------------------------------------------
>
> Key: CALCITE-1862
> URL: https://issues.apache.org/jira/browse/CALCITE-1862
> Project: Calcite
> Issue Type: Bug
> Reporter: Julian Hyde
> Assignee: Julian Hyde
> Priority: Major
>
> The query
> {code}select *
> from (
> select *
> from (
> select cast(null as integer) as d
> from "scott".emp)
> where d is null and d is null)
> where d is null;{code}
> gives
> {noformat}
> java.lang.StackOverflowError
> > at
> > org.apache.calcite.adapter.clone.ArrayTable.getStatistic(ArrayTable.java:76)
> > at
> > org.apache.calcite.prepare.RelOptTableImpl.getRowCount(RelOptTableImpl.java:224)
> > at
> > org.apache.calcite.rel.core.TableScan.estimateRowCount(TableScan.java:75)
> > at
> > org.apache.calcite.rel.metadata.RelMdRowCount.getRowCount(RelMdRowCount.java:206)
> > at GeneratedMetadataHandler_RowCount.getRowCount_$(Unknown Source)
> > at GeneratedMetadataHandler_RowCount.getRowCount(Unknown Source)
> > at
> > org.apache.calcite.rel.metadata.RelMetadataQuery.getRowCount(RelMetadataQuery.java:236)
> > at
> > org.apache.calcite.rel.metadata.RelMdRowCount.getRowCount(RelMdRowCount.java:71)
> > at GeneratedMetadataHandler_RowCount.getRowCount_$(Unknown Source)
> > at GeneratedMetadataHandler_RowCount.getRowCount(Unknown Source)
> > at
> > org.apache.calcite.rel.metadata.RelMetadataQuery.getRowCount(RelMetadataQuery.java:236)
> > at
> > org.apache.calcite.rel.metadata.RelMdUtil.estimateFilteredRows(RelMdUtil.java:718)
> > at
> > org.apache.calcite.rel.metadata.RelMdRowCount.getRowCount(RelMdRowCount.java:123)
> > at GeneratedMetadataHandler_RowCount.getRowCount_$(Unknown Source)
> > at GeneratedMetadataHandler_RowCount.getRowCount(Unknown Source)
> > at
> > org.apache.calcite.rel.metadata.RelMetadataQuery.getRowCount(RelMetadataQuery.java:236)
> > at
> > org.apache.calcite.rel.metadata.RelMdRowCount.getRowCount(RelMdRowCount.java:71)
> > at GeneratedMetadataHandler_RowCount.getRowCount_$(Unknown Source)
> > at GeneratedMetadataHandler_RowCount.getRowCount(Unknown Source)
> > at
> > org.apache.calcite.rel.metadata.RelMetadataQuery.getRowCount(RelMetadataQuery.java:236)
> > at
> > org.apache.calcite.rel.metadata.RelMdUtil.estimateFilteredRows(RelMdUtil.java:718){noformat}
> For a test case, add the query to misc.iq and run QuidemTest.
--
This message was sent by Atlassian JIRA
(v7.6.3#76005)
