[ https://issues.apache.org/jira/browse/CALCITE-3926?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]
Ruben Q L reassigned CALCITE-3926: ---------------------------------- Assignee: Ruben Q L > CannotPlanException when an empty LogicalValues requires a certain collation > ---------------------------------------------------------------------------- > > Key: CALCITE-3926 > URL: https://issues.apache.org/jira/browse/CALCITE-3926 > Project: Calcite > Issue Type: Bug > Components: core > Affects Versions: 1.22.0 > Reporter: Ruben Q L > Assignee: Ruben Q L > Priority: Blocker > Labels: pull-request-available > Fix For: 1.23.0 > > Time Spent: 8h > Remaining Estimate: 0h > > The issue can be reproduced with the following test (in RelBuilderTest.java): > {code:java} > @Test void testEmptyValues() throws Exception { > final RelBuilder builder = RelBuilder.create(config().build()); > final RelNode root = > builder > .scan("DEPT") > .filter(builder.literal(false)) // generates an empty > LogicalValues > .sort( > builder.field("DNAME"), > builder.field("DEPTNO")) > .build(); > try (PreparedStatement preparedStatement = RelRunners.run(root)) { > final String s = > CalciteAssert.toString(preparedStatement.executeQuery()); > final String result = ""; > assertThat(s, is(result)); > } > } > {code} > The test fails with the following message: > {code:java} > Caused by: org.apache.calcite.plan.RelOptPlanner$CannotPlanException: There > are not enough rules to produce a node with desired properties: > convention=ENUMERABLE, sort=[1, 0]. > Missing conversion is LogicalValues[convention: NONE -> ENUMERABLE, sort: > [[0, 1, 2], [1, 2], [2]] -> [1, 0]] > There is 1 empty subset: rel#14:Subset#0.ENUMERABLE.[1, 0], the relevant part > of the original plan is as follows > 1:LogicalValues(tuples=[[]]) > {code} > The issue seems to be caused by the empty values: Scan + Filter(false) => > LogicalValues(tuples=[[]]). > This empty LogicalValues has as collation (in case of 3 fields): [[0, 1, 2], > [1, 2], [2]]; and in the plan we are requesting as sort collation [1, 0]. > This could be achieved by: EnumerableSort(sort=[1,0]) + > EnumerableValues(tuples=[[]]) ; but for some reason this plan is not > generated. > It seems the issue was somehow introduced by CALCITE-3886 > > [https://github.com/apache/calcite/commit/08f4a9889728f94903ff424ed9c20d940b821af5] -- This message was sent by Atlassian Jira (v8.3.4#803005)