asterixdb/asterix-app/src/test/resources/optimizerts/results_cbo/btree-index-selection/btree-index-composite-key-04.plan

-- DISTRIBUTE_RESULT  |PARTITIONED|
  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
    -- STREAM_PROJECT  |PARTITIONED|
      -- ASSIGN  |PARTITIONED|
        -- SORT_MERGE_EXCHANGE [$$22(ASC) ]  |PARTITIONED|
          -- STABLE_SORT [$$22(ASC)]  |PARTITIONED|
            -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
              -- STREAM_SELECT  |PARTITIONED|
                -- STREAM_PROJECT  |PARTITIONED|
                  -- ASSIGN  |PARTITIONED|
                    -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
                      -- DATASOURCE_SCAN (test.employee)  |PARTITIONED|
                        -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
                          -- EMPTY_TUPLE_SOURCE  |PARTITIONED|