[CALCITE-2039] AssertionError when pushing project to ProjectableFilterableTable

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 1.14.0
• Fix Version/s: 1.15.0
• Component/s: core
• Assignee: Michael Mior
• Reporter: Alexey Roytman
• Created: 07/Nov/17 14:33
• Updated: 12/Oct/19 04:08
• Resolved: 16/Nov/17 06:49

Description

When my table implements interface ProjectableFilterableTable, and I execute a query that contains column but also an expression, with assertions enabled (java -ea), I get an AssertionError at Mappings.create(Mappings.java:64).

The following query (notice the "select 0 as c1, ...")

select 0 as c1, D101.c1 as c3, D101.c2 as c4, D101.c3 as c5 from (
  select T1000001.Category as c1, T1000001.Revenue as c2,
  T1000001."YEAR" as c3 from (
    select "YEAR", Category, "MONTH", Territory, Quarter, Sub_Category,
    Age_Group, Gender, Country, Revenue, Num_Of_Orders, "DATE" from
      XSchema.HDP) T1000001) D101

causes an exception:

java.lang.AssertionError
	at org.apache.calcite.util.mapping.Mappings.create(Mappings.java:64)
	at org.apache.calcite.rel.core.Project.getMapping(Project.java:277)
	at org.apache.calcite.rel.core.Project.getMapping(Project.java:257)
	at org.apache.calcite.rel.rules.ProjectTableScanRule.apply(ProjectTableScanRule.java:100)
	at org.apache.calcite.rel.rules.ProjectTableScanRule$3.onMatch(ProjectTableScanRule.java:83)
	at org.apache.calcite.plan.volcano.VolcanoRuleCall.onMatch(VolcanoRuleCall.java:212)
	at org.apache.calcite.plan.volcano.VolcanoPlanner.findBestExp(VolcanoPlanner.java:650)
	at org.apache.calcite.tools.Programs$5.run(Programs.java:326)
	at org.apache.calcite.tools.Programs$SequenceProgram.run(Programs.java:387)
	at org.apache.calcite.prepare.Prepare.optimize(Prepare.java:188)
	at org.apache.calcite.prepare.Prepare.prepareSql(Prepare.java:321)
	at org.apache.calcite.prepare.Prepare.prepareSql(Prepare.java:230)
	at org.apache.calcite.prepare.CalcitePrepareImpl.prepare2_(CalcitePrepareImpl.java:786)
	at org.apache.calcite.prepare.CalcitePrepareImpl.prepare_(CalcitePrepareImpl.java:640)
	at org.apache.calcite.prepare.CalcitePrepareImpl.prepareSql(CalcitePrepareImpl.java:610)
	at org.apache.calcite.jdbc.CalciteConnectionImpl.parseQuery(CalciteConnectionImpl.java:221)
	at org.apache.calcite.jdbc.CalciteMetaImpl.prepareAndExecute(CalciteMetaImpl.java:603)
	at org.apache.calcite.avatica.AvaticaConnection.prepareAndExecuteInternal(AvaticaConnection.java:638)
	at org.apache.calcite.avatica.AvaticaStatement.executeInternal(AvaticaStatement.java:149)
	at org.apache.calcite.avatica.AvaticaStatement.executeQuery(AvaticaStatement.java:218)
        ...

In the Mappings.create(), mappingType is INVERSE_SURJECTION, and "assert sourceCount >= targetCount" throws the exception, because sourceCount is 3, and targetCount is 4.
At the frame above, in Project.getMapping(), "projects" are: [0, $1, $2, $0] (1st is RexLiteral, others are RexInputRef). At the frame above, in EnumerableProject.getMapping(), getInput().getRowType() has only 3 fields in the table.

I have a reproduction case (in Java) but it's not within a Calcite standard.

Issue Links

• is related to: CALCITE-3405 Prune columns for ProjectableFilterableTable when Project is not simple mapping