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https://issues.apache.org/jira/browse/CALCITE-1862?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16391001#comment-16391001
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zhen wang commented on CALCITE-1862:
------------------------------------
some findings
the estimate row count method it self is actually okay. before planner
optimization it can derive the correct row count
the problem lies in the optimization, as rules gets applied on the relation
algebra, the plan becomes deeper and deeper, when the stack overflow, the
algebra has grown to a depth > 100 which essentially lead to the stack
overflow.
haven't located which rule is actually leading to the growth of the relation
algebra.
> 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.
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