[CALCITE-2124] AggregateExpandDistinctAggregatesRule should make SUM nullable if there is no GROUP BY

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 1.15.0
• Fix Version/s: 1.16.0
• Component/s: core
• Assignee: Julian Hyde
• Reporter: godfrey he
• Created: 06/Jan/18 09:14
• Updated: 27/Feb/24 22:23
• Resolved: 11/Jan/18 07:35

Description

AggregateExpandDistinctAggregatesRule should make SUM nullable if there is no GROUP BY. The following test gives aggCall type mismatch error:

@Test public void testDistinctCountWithoutGroupBy() {
     final HepProgram program = HepProgram.builder()
        .addRuleInstance(AggregateExpandDistinctAggregatesRule.INSTANCE)
        .addRuleInstance(AggregateProjectMergeRule.INSTANCE)
        .build();
    checkPlanning(program,
        "select max(deptno), count(distinct ename) from sales.emp");
  }

exception:

java.lang.AssertionError: type mismatch:
aggCall type:
INTEGER
inferred type:
INTEGER NOT NULL

	at org.apache.calcite.util.Litmus$1.fail(Litmus.java:31)
	at org.apache.calcite.plan.RelOptUtil.eq(RelOptUtil.java:1838)
	at org.apache.calcite.rel.core.Aggregate.typeMatchesInferred(Aggregate.java:428)
	at org.apache.calcite.rel.core.Aggregate.<init>(Aggregate.java:161)
	at org.apache.calcite.rel.logical.LogicalAggregate.<init>(LogicalAggregate.java:65)
	at org.apache.calcite.rel.logical.LogicalAggregate.create_(LogicalAggregate.java:110)
	at org.apache.calcite.rel.logical.LogicalAggregate.create(LogicalAggregate.java:100)
	at org.apache.calcite.rel.core.RelFactories$AggregateFactoryImpl.createAggregate(RelFactories.java:213)
	at org.apache.calcite.tools.RelBuilder.aggregate(RelBuilder.java:1268)
	at org.apache.calcite.tools.RelBuilder.aggregate(RelBuilder.java:1840)
	at org.apache.calcite.rel.rules.AggregateExpandDistinctAggregatesRule.rewriteUsingGroupingSets(AggregateExpandDistinctAggregatesRule.java:413)
	at org.apache.calcite.rel.rules.AggregateExpandDistinctAggregatesRule.onMatch(AggregateExpandDistinctAggregatesRule.java:172)
	at org.apache.calcite.plan.AbstractRelOptPlanner.fireRule(AbstractRelOptPlanner.java:317)
	at org.apache.calcite.plan.hep.HepPlanner.applyRule(HepPlanner.java:508)
	at org.apache.calcite.plan.hep.HepPlanner.applyRules(HepPlanner.java:387)
	at org.apache.calcite.plan.hep.HepPlanner.executeInstruction(HepPlanner.java:252)
	at org.apache.calcite.plan.hep.HepInstruction$RuleInstance.execute(HepInstruction.java:127)
	at org.apache.calcite.plan.hep.HepPlanner.executeProgram(HepPlanner.java:211)
	at org.apache.calcite.plan.hep.HepPlanner.findBestExp(HepPlanner.java:198)
	at org.apache.calcite.test.RelOptTestBase.checkPlanning(RelOptTestBase.java:165)
	at org.apache.calcite.test.RelOptTestBase.checkPlanning(RelOptTestBase.java:120)
	at org.apache.calcite.test.RelOptTestBase.checkPlanning(RelOptTestBase.java:95)
	at org.apache.calcite.test.RelOptTestBase.checkPlanning(RelOptTestBase.java:84)
	at org.apache.calcite.test.RelOptRulesTest.testDistinctCountWithoutGroupBy(RelOptRulesTest.java:761)