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https://issues.apache.org/jira/browse/CALCITE-6193?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17804528#comment-17804528
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Julian Hyde commented on CALCITE-6193:
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This bug looks legitimate. However, it would be useful if you can characterize
which kinds of materialized view suffer from this problem. Our users reading
the release notes may not be familiar with SubstitutionVisitor.
> SubstitutionVisitor stop trying incorrect subtree because of wrong parent
> relationship when replace query
> ---------------------------------------------------------------------------------------------------------
>
> Key: CALCITE-6193
> URL: https://issues.apache.org/jira/browse/CALCITE-6193
> Project: Calcite
> Issue Type: Bug
> Reporter: Mou Wu
> Assignee: Mou Wu
> Priority: Major
> Labels: pull-request-available
>
> {code:java}
> @Test void testStopTryIncorrectSubtree() {
> final String mv = ""
> + "select \"empid\", \"deptno\"\n"
> + "from \"emps\"\n"
> + "where \"salary\" > 1000\n"
> + "group by \"empid\", \"deptno\"";
> final String query = ""
> + "select t1.\"deptno\"\n"
> + "from (\n"
> + "select \"deptno\"\n"
> + "from \"emps\"\n"
> + "where \"salary\" > 1000\n"
> + "union all\n"
> + "select \"deptno\"\n"
> + "from \"emps\"\n"
> + "where \"salary\" > 1000\n"
> + "group by \"deptno\"\n"
> + ") as t1 inner join (\n"
> + "select \"deptno\"\n"
> + "from \"emps\"\n"
> + "where \"salary\" > 1000\n"
> + "group by \"deptno\"\n"
> + ") as t2 on t1.\"deptno\" = t2.\"deptno\"\n";
> sql(mv, query)
> .checkingThatResultContains(""
> + "LogicalCalc(expr#0..1=[{inputs}], deptno=[$t0])\n"
> + " LogicalJoin(condition=[=($0, $1)], joinType=[inner])\n"
> + " LogicalUnion(all=[true])\n"
> + " LogicalCalc(expr#0..4=[{inputs}], expr#5=[1000],
> expr#6=[>($t3, $t5)], deptno=[$t1], $condition=[$t6])\n"
> + " LogicalTableScan(table=[[hr, emps]])\n"
> + " LogicalAggregate(group=[{1}])\n"
> + " EnumerableTableScan(table=[[hr, MV0]])\n"
> + " LogicalAggregate(group=[{1}])\n"
> + " EnumerableTableScan(table=[[hr, MV0]])"
> ).ok();
> }{code}
> The test case above will fail because the second mv0 not be matched.
> The root cause is that SubstitutionVisitor replace child nodes withÂ
> targetDescendant node itself, not a deep-copy replica, so they may share the
> same node and the same parent node, thus the incorrect parent relationship
> may occur, it will make stopTrying be wrong.
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