Zoltan Haindrich created CALCITE-2675: -----------------------------------------
Summary: ReduceExpressionRule may leave behind altered types w.r.t nullability Key: CALCITE-2675 URL: https://issues.apache.org/jira/browse/CALCITE-2675 Project: Calcite Issue Type: Bug Reporter: Zoltan Haindrich Assignee: Zoltan Haindrich If a simplification could happen after some [ReduceExpression rewrite|https://github.com/apache/calcite/blob/fcc8bf7f44f92efb3c9a1e1f51ffc1a09cab27b9/core/src/main/java/org/apache/calcite/rel/rules/ReduceExpressionsRule.java#L794]; the simplification result may have a slightly different type in nullability. {code} @Test public <T> void testReduceCaseNullabilityChange() throws Exception { HepProgram program = new HepProgramBuilder() .addRuleInstance(ReduceExpressionsRule.FILTER_INSTANCE) .addRuleInstance(ReduceExpressionsRule.PROJECT_INSTANCE) .build(); try (Hook.Closeable a = Hook.REL_BUILDER_SIMPLIFY.add(Hook.propertyJ(false))) { checkPlanning(program, "select case when empno = 1 then 1 when 1 IS NOT NULL then 2 else null end as qx " + "from emp"); } {code} Exposed by CALCITE-1413 changes; I'm not sure if there is any other variations for which the same could happen. -- This message was sent by Atlassian JIRA (v7.6.3#76005)