sql如下:SELECT  A.ASSEDT,A.OBJSID,B.ACCTID,A.RELART,A.ACCTFG
  FROM FDM_PAMS_OUT_ACCT_TMP1 A , ODS.DCAM_DPAC B 
  WHERE (CASE WHEN A.ACCTNO=B.ACCTNO THEN B.ACCTNO ELSE B.ACCTID END)=A.ACCTNO AND B.ACCTDT=TO_DATE('20111231','YYYYMMDD')执行计划(用explain plan for):
1 Plan hash value: 1941993489
2  
3 ---------------------------------------------------------------------------------------------------------------------------------------------
4 | Id  | Operation             | Name                   | Rows  | Bytes | Cost (%CPU)| Time     | Pstart| Pstop |    TQ  |IN-OUT| PQ Distrib |
5 ---------------------------------------------------------------------------------------------------------------------------------------------
6 |   0 | SELECT STATEMENT      |                        |    13M|  1304M|   642M  (1)|999:59:59 |       |       |        |      |            |
7 |   1 |  PX COORDINATOR       |                        |       |       |            |          |       |       |        |      |            |
8 |   2 |   PX SEND QC (RANDOM) | :TQ10000               |    13M|  1304M|   642M  (1)|999:59:59 |       |       |  Q1,00 | P->S | QC (RAND)  |
9 |   3 |    NESTED LOOPS       |                        |    13M|  1304M|   642M  (1)|999:59:59 |       |       |  Q1,00 | PCWP |            |
10 |   4 |     PX BLOCK ITERATOR |                        |  5982K|   233M|  7276   (1)| 00:01:28 |     1 |     2 |  Q1,00 | PCWC |            |
11 |*  5 |      TABLE ACCESS FULL| DCAM_DPAC              |  5982K|   233M|  7276   (1)| 00:01:28 |     1 |     2 |  Q1,00 | PCWP |            |
12 |*  6 |     TABLE ACCESS FULL | FDM_PAMS_OUT_ACCT_TMP1 |     2 |   118 |   773   (1)| 00:00:10 |       |       |  Q1,00 | PCWP |            |
13 ---------------------------------------------------------------------------------------------------------------------------------------------
14  
15 Predicate Information (identified by operation id):
16 ---------------------------------------------------
17  
18    5 - filter("B"."ACCTDT"=TO_DATE(' 2011-12-31 00:00:00', 'syyyy-mm-dd hh24:mi:ss'))
19    6 - filter("A"."ACCTNO"=CASE "A"."ACCTNO" WHEN "B"."ACCTNO" THEN "B"."ACCTNO" ELSE "B"."ACCTID" END )