I have the following tables with a one to many relationship between
c_hdr_common_t and c_li_exc_t.

SQL> desc msdss.c_hdr_common_t
 Name                                      Null?    Type
 ----------------------------------------- -------- ------------
 C_HDR_PD_DT                               NOT NULL DATE
 B_SYS_ID                                  NOT NULL NUMBER(9)
 C_TCN_NUM                                 NOT NULL CHAR(17)
 C_TOT_REIMB_AMT                                    NUMBER(11,2)
..................


SQL> desc msdss.c_li_exc_t
 Name                                      Null?    Type
 ----------------------------------------- -------- -----------
 C_HDR_PD_DT                               NOT NULL DATE
 B_SYS_ID                                  NOT NULL NUMBER(9)
 C_TCN_NUM                                 NOT NULL CHAR(17)
 C_LI_NUM                                  NOT NULL NUMBER(4)
 R_CLM_EXC_CD                              NOT NULL CHAR(4)
..............


I want to be able to create an object view (or maybe something else) that will 
allow me to return 1 occurence of c_hdr_common_t that matches a list of R_CLM_EXC_CD's.

such as:
SELECT a.B_SYS_ID,a.C_HDR_PD_DT,a.C_TCN_NUM,a.
FROM msdss.clm_hdr_view a
WHERE c_hdr_pd_dt = '22-DEC-2003'
AND  R_CLM_EXC_CD IN ('0423','0230')

I have tried creating the object views below, but still can't get it to the point of returning 
one occurence. Simply adding DISTINCT to the above query is not an option. I want to be able to use
this view to group by and sum on other data in c_hdr_common_t.

CREATE TYPE msdss.clm_exc_t AS OBJECT
(
  R_CLM_EXC_CD CHAR(4)
);

CREATE TYPE msdss.clm_exc_list_t AS TABLE OF clm_exc_t;

CREATE TYPE msdss.clm_hdr_t AS OBJECT
(   C_HDR_PD_DT DATE,
    B_SYS_ID NUMBER(9),
    C_TCN_NUM CHAR(17),
    clm_exc_list   clm_exc_list_t
);

CREATE VIEW msdss.clm_hdr_view OF clm_hdr_t WITH OBJECT IDENTIFIER (C_HDR_PD_DT,B_SYS_ID,C_TCN_NUM) AS
    SELECT a.C_HDR_PD_DT,a.B_SYS_ID,a.C_TCN_NUM,
            CAST( MULTISET (
                           SELECT DISTINCT(b.R_CLM_EXC_CD) 
                           FROM msdss.c_li_exc_t b 
                           WHERE a.C_HDR_PD_DT = b.C_HDR_PD_DT
                           AND a.B_SYS_ID = b.B_SYS_ID
                           AND a.C_TCN_NUM = b.C_TCN_NUM) 
                        AS clm_exc_list_t)
                   AS clm_exc_list
   FROM   msdss.c_hdr_common_t a


thanks.