错误的选择了HASH JOIN！

explain plan for select
a.open_org as 机构号,
a.org_name as 机构名,
b.cur_cd as 币种,
sum(b.acct_bal)/10000 as 余额,
count(*) as 户数

from
( select /*+ leading(y) use_nl(x y)*/  x.open_org , x.agmt_id , x.cust_no , y.org_name
from dwf.F_AGT_SAVB_BASICINFO_H x , dwm.B_M_SYS_BRANCH y
where x.start_dt<= to_date('2014-01-01', 'YYYY-MM-DD')
and x.end_dt> to_date('2014-01-01', 'YYYY-MM-DD') 
and x.acct_status in('0','S')
and substr(x.cust_no,1,1) in('0','8','9','a')
and x.open_org = y.org_id
and y.parent_id='1015'
)a,


(
select *
from dwf.F_AGT_SAVB_ACCTINFO_H 
where substr(subj_cd,1,3) in(201,202,205,251)
and start_dt<= to_date('2014-01-01', 'YYYY-MM-DD')
and end_dt> to_date('2014-01-01', 'YYYY-MM-DD')
)b,


(
select * from dwf.F_PTY_TABLE
where start_dt<= to_date('2014-01-01', 'YYYY-MM-DD')
and end_dt> to_date('2014-01-01', 'YYYY-MM-DD')
and corp_org='15601'
and area_code <>'3310'
)c

where a.agmt_id=b.agmt_id
and a.cust_no=c.pty_id
group by a.open_org,a.org_name,b.cur_cd
;
Plan hash value: 249788832
 
---------------------------------------------------------------------------------------------------------
| Id  | Operation                      | Name                   | Rows  | Bytes | Cost (%CPU)| Time     |
---------------------------------------------------------------------------------------------------------
|   0 | SELECT STATEMENT               |                        |  1873 |   347K| 58231   (1)| 00:11:39 |
|   1 |  HASH GROUP BY                 |                        |  1873 |   347K| 58231   (1)| 00:11:39 |
|*  2 |   HASH JOIN                    |                        |  3056 |   567K| 58230   (1)| 00:11:39 |
|   3 |    NESTED LOOPS                |                        |  2981 |   416K| 51040   (1)| 00:10:13 |
|   4 |     NESTED LOOPS               |                        | 27214 |   416K| 51040   (1)| 00:10:13 |
|*  5 |      HASH JOIN                 |                        |  2474 |   215K| 16383   (2)| 00:03:17 |
|*  6 |       TABLE ACCESS FULL        | B_M_SYS_BRANCH         |     5 |   125 |     3   (0)| 00:00:01 |
|*  7 |       TABLE ACCESS FULL        | F_AGT_SAVB_BASICINFO_H | 55736 |  3483K| 16379   (2)| 00:03:17 |
|*  8 |      INDEX RANGE SCAN          | SYS_C00224616          |    11 |       |     3   (0)| 00:00:01 |
|*  9 |     TABLE ACCESS BY INDEX ROWID| F_AGT_SAVB_ACCTINFO_H  |     1 |    54 |    14   (0)| 00:00:01 |
|* 10 |    TABLE ACCESS FULL           | F_PTY_TABLE            |   103K|  4730K|  7189   (2)| 00:01:27 |
---------------------------------------------------------------------------------------------------------
 
Predicate Information (identified by operation id):
---------------------------------------------------
 
   2 - access("X"."CUST_NO"="F_PTY_TABLE"."PTY_ID")
   5 - access("X"."OPEN_ORG"="Y"."ORG_ID")
   6 - filter("Y"."PARENT_ID"=1015)
   7 - filter(("X"."ACCT_STATUS"='0' OR "X"."ACCT_STATUS"='S') AND "X"."START_DT"<=TO_DATE(' 
              2014-01-01 00:00:00', 'syyyy-mm-dd hh24:mi:ss') AND (SUBSTR("X"."CUST_NO",1,1)='0' OR 
              SUBSTR("X"."CUST_NO",1,1)='8' OR SUBSTR("X"."CUST_NO",1,1)='9' OR SUBSTR("X"."CUST_NO",1,1)='a') 
              AND "X"."END_DT">TO_DATE(' 2014-01-01 00:00:00', 'syyyy-mm-dd hh24:mi:ss'))
   8 - access("X"."AGMT_ID"="F_AGT_SAVB_ACCTINFO_H"."AGMT_ID" AND "START_DT"<=TO_DATE(' 
              2014-01-01 00:00:00', 'syyyy-mm-dd hh24:mi:ss'))
       filter("START_DT"<=TO_DATE(' 2014-01-01 00:00:00', 'syyyy-mm-dd hh24:mi:ss'))
   9 - filter((TO_NUMBER(SUBSTR("SUBJ_CD",1,3))=201 OR TO_NUMBER(SUBSTR("SUBJ_CD",1,3))=202 OR 
              TO_NUMBER(SUBSTR("SUBJ_CD",1,3))=205 OR TO_NUMBER(SUBSTR("SUBJ_CD",1,3))=251) AND 
              "END_DT">TO_DATE(' 2014-01-01 00:00:00', 'syyyy-mm-dd hh24:mi:ss'))
  10 - filter("CORP_ORG"='15601' AND "START_DT"<=TO_DATE(' 2014-01-01 00:00:00', 'syyyy-mm-dd 
              hh24:mi:ss') AND "END_DT">TO_DATE(' 2014-01-01 00:00:00', 'syyyy-mm-dd hh24:mi:ss') AND 
              "AREA_CODE"<>'3310')


这里 select count(*) from B_M_SYS_BRANCH Y where ("Y"."PARENT_ID"=1015)
select count(*) from B_M_SYS_BRANCH Y where ("Y"."PARENT_ID"=1015)
--9

这里ID=6 才返回9条记录,没必要走HASH JOIN,只需要B_M_SYS_BRANCH  作为驱动表去驱动F_AGT_SAVB_BASICINFO_H即可

创建如下索引:
create index F_AGT_SAVB_BASICINFO_H_IDX3  on F_AGT_SAVB_BASICINFO_H(OPEN_ORG,ACCT_STATUS,SUBSTR("CUST_NO",1,1))

select
a.open_org as 机构号,
a.org_name as 机构名,
b.cur_cd as 币种,
sum(b.acct_bal)/10000 as 余额,
count(*) as 户数

from
( select /*+ leading(y) use_nl(x y)*/  x.open_org , x.agmt_id , x.cust_no , y.org_name
from dwf.F_AGT_SAVB_BASICINFO_H x , dwm.B_M_SYS_BRANCH y
where x.start_dt<= to_date('2014-01-01', 'YYYY-MM-DD')
and x.end_dt> to_date('2014-01-01', 'YYYY-MM-DD') 
and x.acct_status in('0','S')
and substr(x.cust_no,1,1) in('0','8','9','a')
and x.open_org = y.org_id
and y.parent_id='1015'
)a,


(
select *
from dwf.F_AGT_SAVB_ACCTINFO_H 
where substr(subj_cd,1,3) in(201,202,205,251)
and start_dt<= to_date('2014-01-01', 'YYYY-MM-DD')
and end_dt> to_date('2014-01-01', 'YYYY-MM-DD')
)b,


(
select * from dwf.F_PTY_TABLE
where start_dt<= to_date('2014-01-01', 'YYYY-MM-DD')
and end_dt> to_date('2014-01-01', 'YYYY-MM-DD')
and corp_org='15601'
and area_code <>'3310'
)c

where a.agmt_id=b.agmt_id
and a.cust_no=c.pty_id
group by a.open_org,a.org_name,b.cur_cd
;


Plan hash value: 1581029793
 
-----------------------------------------------------------------------------------------------------------------
| Id  | Operation                         | Name                        | Rows  | Bytes | Cost (%CPU)| Time     |
-----------------------------------------------------------------------------------------------------------------
|   0 | SELECT STATEMENT                  |                             |   644 |   121K| 28461   (1)| 00:05:42 |
|   1 |  HASH GROUP BY                    |                             |   644 |   121K| 28461   (1)| 00:05:42 |
|   2 |   NESTED LOOPS                    |                             |   644 |   121K| 28460   (1)| 00:05:42 |
|   3 |    NESTED LOOPS                   |                             |  5874 |   121K| 28460   (1)| 00:05:42 |
|   4 |     NESTED LOOPS                  |                             |   534 | 74226 | 20980   (1)| 00:04:12 |
|   5 |      NESTED LOOPS                 |                             |   521 | 47932 | 19416   (1)| 00:03:53 |
|*  6 |       TABLE ACCESS FULL           | B_M_SYS_BRANCH              |     5 |   125 |     3   (0)| 00:00:01 |
|   7 |       INLIST ITERATOR             |                             |       |       |            |          |
|*  8 |        TABLE ACCESS BY INDEX ROWID| F_AGT_SAVB_BASICINFO_H      |   110 |  7370 |  5495   (1)| 00:01:06 |
|*  9 |         INDEX RANGE SCAN          | F_AGT_SAVB_BASICINFO_H_IDX3 | 13903 |       |    49   (0)| 00:00:01 |
|* 10 |      TABLE ACCESS BY INDEX ROWID  | F_PTY_TABLE                 |     1 |    47 |     3   (0)| 00:00:01 |
|* 11 |       INDEX RANGE SCAN            | SYS_C00224099               |     1 |       |     2   (0)| 00:00:01 |
|* 12 |     INDEX RANGE SCAN              | SYS_C00224616               |    11 |       |     3   (0)| 00:00:01 |
|* 13 |    TABLE ACCESS BY INDEX ROWID    | F_AGT_SAVB_ACCTINFO_H       |     1 |    54 |    14   (0)| 00:00:01 |
-----------------------------------------------------------------------------------------------------------------
 
Predicate Information (identified by operation id):
---------------------------------------------------
 
   6 - filter("Y"."PARENT_ID"=1015)
   8 - filter("X"."START_DT"<=TO_DATE(' 2014-01-01 00:00:00', 'syyyy-mm-dd hh24:mi:ss') AND 
              "X"."END_DT">TO_DATE(' 2014-01-01 00:00:00', 'syyyy-mm-dd hh24:mi:ss'))
   9 - access("X"."OPEN_ORG"="Y"."ORG_ID" AND ("X"."ACCT_STATUS"='0' OR "X"."ACCT_STATUS"='S') AND 
              (SUBSTR("CUST_NO",1,1)='0' OR SUBSTR("CUST_NO",1,1)='8' OR SUBSTR("CUST_NO",1,1)='9' OR 
              SUBSTR("CUST_NO",1,1)='a'))
  10 - filter("END_DT">TO_DATE(' 2014-01-01 00:00:00', 'syyyy-mm-dd hh24:mi:ss') AND "AREA_CODE"<>'3310')
  11 - access("X"."CUST_NO"="F_PTY_TABLE"."PTY_ID" AND "CORP_ORG"='15601' AND "START_DT"<=TO_DATE(' 
              2014-01-01 00:00:00', 'syyyy-mm-dd hh24:mi:ss'))
       filter("CORP_ORG"='15601' AND "START_DT"<=TO_DATE(' 2014-01-01 00:00:00', 'syyyy-mm-dd 
              hh24:mi:ss') AND SUBSTR("CUST_NO",1,1)=SUBSTR("F_PTY_TABLE"."PTY_ID",1,1))
  12 - access("X"."AGMT_ID"="F_AGT_SAVB_ACCTINFO_H"."AGMT_ID" AND "START_DT"<=TO_DATE(' 2014-01-01 
              00:00:00', 'syyyy-mm-dd hh24:mi:ss'))
       filter("START_DT"<=TO_DATE(' 2014-01-01 00:00:00', 'syyyy-mm-dd hh24:mi:ss'))
  13 - filter((TO_NUMBER(SUBSTR("SUBJ_CD",1,3))=201 OR TO_NUMBER(SUBSTR("SUBJ_CD",1,3))=202 OR 
              TO_NUMBER(SUBSTR("SUBJ_CD",1,3))=205 OR TO_NUMBER(SUBSTR("SUBJ_CD",1,3))=251) AND "END_DT">TO_DATE(' 
              2014-01-01 00:00:00', 'syyyy-mm-dd hh24:mi:ss'))