[CALCITE-4734] If there are duplicate RexNode in MutableCalc, SubstitutionVisitor should return right rebuild RexNode

• Type: Bug
• Status: Closed
• Priority: Critical
• Resolution: Fixed
• Fix Version/s: 1.28.0
• Component/s: core
• Labels: pull-request-available
• Assignee: Unassigned
• Reporter: Xurenhe
• Created: 13/Aug/21 03:45
• Updated: 20/Oct/21 05:25
• Resolved: 01/Sep/21 06:34

Description

Some user may define some not beautiful mv, but these mv should be worked for rewriting query.
For example:

  @Test void testMoreSameExprInMv() {
    final String mv = ""
        + "select \"empid\", \"deptno\", sum(\"empid\") as s1, sum(\"empid\") as s2, count(*) as c\n"
        + "from \"emps\" group by \"empid\", \"deptno\"";
    final String query = ""
        +  "select sum(\"empid\"), count(*) from \"emps\" group by \"empid\", \"deptno\"";
    sql(mv, query).ok();
  }

I try debug code to solve this problem.
I find some bug in

org.apache.calcite.plan.SubstitutionVisitor#getRexShuttle

PR: https://github.com/apache/calcite/pull/2484
Please review, THX.

Issue Links

• links to: GitHub Pull Request #2484