Error in view

Question

I am getting an error : ORA-00904: "CD_REGION_V"."CODE_KEY": invalid identifier
00904. 00000 - "%s: invalid identifier"
*Cause:  
ORACLE 11G
while compiling the procedure map_state_region_v
CREATE OR REPLACE FORCE VIEW map_state_region_v ("st_code", "st_name", "st_display", "rgn_code",
"rgn_name", "rgn_display","o_a_ind","consigned_flag","contract_ind")
AS
   SELECT a.st_code ,
          a.st_name ,
          '(' || RTRIM(a.st_code) || ') - ' || a.st_name  st_display,
          a.rgn_code ,
        cd_region_v.code_desc  ,
        cd_region_v.code_display   ,
          a.o_a_ind ,
          a.consigned_flag ,
          a.contract_ind
     FROM state_t a,
          cd_region_v
     WHERE a.rgn_code =CD_REGION_V.code_key;
---- DEPENDENT ON THIS VIEW (It is compiled
  CREATE OR REPLACE FORCE VIEW "DEMAND"."CD_REGION_V" ("code_tbl_key", "code_key", "code_desc", "code_display", "created_by", "create_date") AS
  SELECT DISTINCT NVL(code_val_t.code_tbl_key, 39) col1 ,
                   NVL(code_val_t.code_value, rgn_code) col2,
                   NVL(code_val_t.code_desc, rgn_code) col3 ,
                   '(' || RTRIM(NVL(code_val_t.code_value, rgn_code)) || ') - ' || RTRIM(NVL(code_val_t.code_desc, rgn_code)) col4,
                   NVL(code_val_t.created_by, 'RFS')  col5,
                   NVL(code_val_t.create_date, '01/07/2010') col6
     FROM code_val_t ,
          fcst_t
     WHERE code_val_t.code_tbl_key = 39
             AND code_value(+) =
           rgn_code;
desc CD_REGION_V
Name         Null Type        
code_tbl_key      NUMBER      
code_key          VARCHAR2(5) 
code_desc         VARCHAR2(30)
code_display      VARCHAR2(40)
created_by        VARCHAR2(8) 
create_date       DATE     Edited by: Rahul_India on Sep 5, 2012 10:39 PM

Answer 1

wrong answer i guess
SELECT a.st_code ,
          a.st_name ,
          '(' || RTRIM(a.st_code) || ') - ' || a.st_name  st_display,
          a.rgn_code ,
          b.code_desc  ,
         b.code_display   ,
          a.o_a_ind ,
          a.consigned_flag ,
          a.contract_ind
     FROM state_t a,
          cd_region_v b
     WHERE a.rgn_code =b.code_key;
ERRROR:
ORA-00904: "B"."CODE_KEY": invalid identifier
00904. 00000 -  "%s: invalid identifier"
*Cause:   
*Action:
Error at Line: 15 Column: 23Why i am getting this?