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oracle with clause and materialize hint

oracle guru Burleson's note  helped me to improve performance on a query cross database link
http://www.dba-oracle.com/t_with_clause.htm

 we have a database link from oracle to MS SQL server using oracle DRDA, the following query take long to complete, I cannot wait for it to complete and have to kill the query.

SELECT count(*) FROM "ContractItem"@QSENCT002 A, "contractheader_cr"@QSENCT002 B
WHERE A. "ContractHeaderID" = B. "contractheaderid"
AND "ContractItemDayID" BETWEEN 37345 AND 37346
and not exists
(SELECT REVENUESTREAMEXPORTID FROM radiostage.REVENUESTREAMEXPORT_XREF WHERE DIVESTED = 'Y' and A."RevenueStreamExportID" =REVENUESTREAMEXPORTID )
/

After re-write the query using with clause and materialize hint, the query complete in 1 second.
However, if I give bigger range of date in the query, the performance is not improved much, so it's depends on case by case.

with ctview as
(select /*+ materialize */ * FROM "ContractItem"@QSENCT002 A, "contractheader_cr"@QSENCT002 B
WHERE A. "ContractHeaderID" = B. "contractheaderid"
AND "ContractItemDayID" BETWEEN 37345 AND 37346)
select count(*) from ctview
where ctview."RevenueStreamExportID" NOT IN (SELECT REVENUESTREAMEXPORTID FROM radiostage.REVENUESTREAMEXPORT_XREF WHERE DIVESTED = 'Y')

/

  COUNT(*)
----------
         0

Elapsed: 00:00:00.88

Execution Plan
----------------------------------------------------------
Plan hash value: 1488614543

--------------------------------------------------------------------------------------------------------------------------
| Id  | Operation                  | Name                        | Rows  | Bytes | Cost (%CPU)| Time  | Inst   |IN-OUT|
--------------------------------------------------------------------------------------------------------------------------
|   0 | SELECT STATEMENT           |                             |     1 |    18 |   406   (1)| 00:00:05 |        |      |
|   1 |  TEMP TABLE TRANSFORMATION |                             |       |       |            |       |   |      |
|   2 |   LOAD AS SELECT           | SYS_TEMP_0FD9D6603_13638A70 |       |       |            |       |   |      |
|   3 |    REMOTE                  |                             |     5 |  1300 |   200   (0)| 00:00:03 | QSENC~ | R->S |
|   4 |   SORT AGGREGATE           |                             |     1 |    18 |            |       |   |      |
|*  5 |    HASH JOIN ANTI NA       |                             |     1 |    18 |     6  (17)| 00:00:01 |        |      |
|   6 |     VIEW                   |                             |     5 |    65 |     2   (0)| 00:00:01 |        |      |
|   7 |      TABLE ACCESS FULL     | SYS_TEMP_0FD9D6603_13638A70 |     5 |  1365 |     2   (0)| 00:00:01 |        |      |
|*  8 |     TABLE ACCESS FULL      | REVENUESTREAMEXPORT_XREF    |     4 |    20 |     3   (0)| 00:00:01 |        |      |
--------------------------------------------------------------------------------------------------------------------------

Predicate Information (identified by operation id):
---------------------------------------------------

   5 - access("CTVIEW"."RevenueStreamExportID"="REVENUESTREAMEXPORTID")
   8 - filter("DIVESTED"='Y')

Remote SQL Information (identified by operation id):
----------------------------------------------------

   3 - SELECT A1."ContractItemID",A1."ContractHeaderID",A1."RevenueStreamExportID",A1."ContractItemDayID",A1."DayP
       artHalfHourID",A1."TransactionDayID",A1."ContractItemStatusID",A1."ContractItemTypeID",A1."SaleTypeID",A1."Industr
       yProductID",A1."TransactionCodeID",A1."AnnouncementTypeID",A1."NumberOfItems",A1."TotalCostGross",A1."TotalCostNet
       ",A1."TotalValueGross",A1."TotalValueNet",A1."IsBroadcast",A1."SpotLengthID",A1."CustomerID",A2."contractheaderid"
        FROM "ContractItem" A1,"contractheader_cr" A2 WHERE A1."ContractHeaderID"=A2."contractheaderid" AND
       A1."ContractItemDayID">=37345 AND A1."ContractItemDayID"<=37346 (accessing 'QSENCT002' )



Statistics
----------------------------------------------------------
        205  recursive calls
          7  db block gets
        217  consistent gets
          9  physical reads
       1392  redo size
        209  bytes sent via SQL*Net to client
        252  bytes received via SQL*Net from client
          2  SQL*Net roundtrips to/from client
          5  sorts (memory)
          0  sorts (disk)
          1  rows processed


11:26:12 RMS8DEV>

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