One Query need to tune

Question

I have one query below to tune.
Here one table USER_RETAILER_MAP and its column BELONGS_TO having value only 'Y' and 'N'.
Created bitmap index but i am not getting any cost difference.
Please share your idea ,how to tune and what process should follow.
SQL> explain plan for
2 SELECT a.user_id,
3 a.user_nm,
4 2 AS max_level
5 FROM gss_user a
6 WHERE a.user_id NOT IN (SELECT user_id
7 FROM user_retailer_map
8 WHERE retailer_id IN (SELECT b.retailer_id
9 FROM user_retailer_map b,
10 retailer c
11 WHERE
12 b.retailer_id = c.retailer_id
13 AND b.user_id = :a
14 AND c.status = 'ACTIVE'
15 AND b.managed_by = 'Y')
16 AND belongs_to = 'Y')
17 AND Upper(a.status) = 'ACTIVE'
18 AND a.user_id IN (SELECT user_id
19 FROM user_hierarchy
20 WHERE parent_user_id = :b)
21 AND a.gmac_dealer_user_flg = 'D'
22 ORDER BY Upper(user_nm) ASC
23 ;
Explained.
SQL> @utlxpls
PLAN_TABLE_OUTPUT
| Id | Operation | Name | Rows | Bytes | Cost |
| 0 | SELECT STATEMENT | | 1 | 91 | 65 |
| 1 | SORT ORDER BY | | 1 | 91 | 65 |
|* 2 | HASH JOIN ANTI | | 1 | 91 | 63 |
| 3 | NESTED LOOPS SEMI | | 7 | 504 | 9 |
|* 4 | TABLE ACCESS FULL | GSS_USER | 33 | 1254 | 9 |
|* 5 | INDEX UNIQUE SCAN | XPKGSS_USER_HIERARCHY | 7 | 238 | |
| 6 | VIEW | VW_NSO_1 | 212 | 4028 | 53 |
|* 7 | HASH JOIN | | 212 | 15476 | 53 |
|* 8 | HASH JOIN | | 15 | 675 | 9 |
| 9 | TABLE ACCESS BY INDEX ROWID| USER_RETAILER_MAP | 15 | 420 | 4 |
|* 10 | INDEX RANGE SCAN | INDX_USERID_MNGBY | 15 | | 1 |
|* 11 | INDEX FAST FULL SCAN | INDX_RETAILE | 1594 | 27098 | 4 |
|* 12 | TABLE ACCESS FULL | USER_RETAILER_MAP | 22885 | 625K| 43 |
Predicate Information (identified by operation id):
2 - access("A"."USER_ID"="VW_NSO_1"."$nso_col_1")
4 - filter(UPPER("A"."STATUS")='ACTIVE' AND "A"."GMAC_DEALER_USER_FLG"='D')
5 - access("A"."USER_ID"="USER_HIERARCHY"."USER_ID" AND "USER_HIERARCHY"."PARENT_USER
_ID"=:Z)
7 - access("USER_RETAILER_MAP"."RETAILER_ID"="B"."RETAILER_ID")
8 - access("B"."RETAILER_ID"="C"."RETAILER_ID")
10 - access("B"."USER_ID"=:Z AND "B"."MANAGED_BY"='Y')
11 - filter("C"."STATUS"='ACTIVE')
12 - filter("USER_RETAILER_MAP"."BELONGS_TO"='Y')
}

Answer 1

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