[ 
https://issues.apache.org/jira/browse/CALCITE-2466?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16580180#comment-16580180
 ] 

Shuyi Chen commented on CALCITE-2466:
-------------------------------------

Thanks a lot, [~julianhyde], in 
{code:java}
select deptno from dept_nested where NAME <> '' AND employees <> null
{code}, 

if NAME is empty string and employees is a valid array (non null), then it 
should not return empty row, right?

> RexSimplify incorrectly simplify conjunction statement with null literal
> ------------------------------------------------------------------------
>
>                 Key: CALCITE-2466
>                 URL: https://issues.apache.org/jira/browse/CALCITE-2466
>             Project: Calcite
>          Issue Type: Bug
>          Components: core
>            Reporter: Shuyi Chen
>            Assignee: Julian Hyde
>            Priority: Major
>             Fix For: 1.18.0
>
>
> This can be reproduced using the following test:
> {code:java}
>  @Test public void testFilterReduction() throws Exception {
>     HepProgramBuilder programBuilder = HepProgram.builder();
>     programBuilder.addRuleInstance(ReduceExpressionsRule.FILTER_INSTANCE);
>     HepPlanner planner = new HepPlanner(programBuilder.build());
>     final String sql = "select deptno from dept_nested where NAME <> '' AND 
> employees <> null";
>     planner.setRoot(tester.convertSqlToRel(sql).rel);
>     RelNode bestRel = planner.findBestExp();
>     assertEquals(
>         "LogicalProject(DEPTNO=[$0])\n" +
>         "  LogicalFilter(condition=[AND(<>($1, ''), <>($3, null))])\n" +
>         "    LogicalTableScan(table=[[CATALOG, SALES, DEPT_NESTED]])\n",
>         RelOptUtil.toString(bestRel));
>   }
> {code}
> In this test, 
> {code:java}
> NAME <> '' AND employees <> null
> {code} is always evaluated to false incorrectly, so the optimized plan is 
> {code:java}
> LogicalProject(DEPTNO=[$0])
>   LogicalValues(tuples=[[]])
> {code}.



--
This message was sent by Atlassian JIRA
(v7.6.3#76005)

Reply via email to