Uploaded image for project: 'Calcite'
  1. Calcite
  2. CALCITE-4333

The Sort rel should be decorrelated even though it has fetch or limit when its parent is not a Correlate

    XMLWordPrintableJSON

    Details

      Description

      Check this test in SqlToRelConverterTest:

      @Test void testSortLimitWithCorrelateInput() {
          final String sql = "" +
              "SELECT deptno, ename\n" +
              "    FROM\n" +
              "        (SELECT DISTINCT deptno FROM emp) t1,\n" +
              "          LATERAL (\n" +
              "            SELECT ename, sal\n" +
              "            FROM emp\n" +
              "            WHERE deptno = t1.deptno)\n" +
              "    ORDER BY ename DESC\n" +
              "    LIMIT 3";
          sql(sql).ok();
        }
      

      The current plan is:

      LogicalSort(sort0=[$1], dir0=[DESC], fetch=[3])
        LogicalProject(DEPTNO=[$0], ENAME=[$1])
          LogicalCorrelate(correlation=[$cor0], joinType=[inner], requiredColumns=[{0}])
            LogicalAggregate(group=[{0}])
              LogicalProject(DEPTNO=[$7])
                LogicalTableScan(table=[[CATALOG, SALES, EMP]])
            LogicalProject(ENAME=[$1], SAL=[$5])
              LogicalFilter(condition=[=($7, $cor0.DEPTNO)])
                LogicalTableScan(table=[[CATALOG, SALES, EMP]])
      

      It actually can be decorrelated to:

      LogicalSort(sort0=[$1], dir0=[DESC], fetch=[3])
        LogicalProject(DEPTNO=[$0], ENAME=[$1])
          LogicalJoin(condition=[=($0, $3)], joinType=[inner])
            LogicalAggregate(group=[{0}])
              LogicalProject(DEPTNO=[$7])
                LogicalTableScan(table=[[CATALOG, SALES, EMP]])
            LogicalProject(ENAME=[$1], SAL=[$5], DEPTNO=[$7])
              LogicalTableScan(table=[[CATALOG, SALES, EMP]])
      

        Attachments

          Issue Links

            Activity

              People

              • Assignee:
                danny0405 Danny Chen
                Reporter:
                danny0405 Danny Chen
              • Votes:
                0 Vote for this issue
                Watchers:
                5 Start watching this issue

                Dates

                • Created:
                  Updated:
                  Resolved:

                  Time Tracking

                  Estimated:
                  Original Estimate - Not Specified
                  Not Specified
                  Remaining:
                  Remaining Estimate - 0h
                  0h
                  Logged:
                  Time Spent - 1.5h
                  1.5h