Query to Join three queries

Question

Hi,
I have three queries as follows. I want to write a single query by using these three queries. can any one please help me out to write the query.
Query 1:
SELECT a_name,
b_item_typ_cd,
item_num,
a_m_name,
DECODE(RTRIM(LTRIM(t_clasfn_cd)),NULL,NULL,
‘X’|| t_clasfn_cd) t_clasfn_cd,
in_splt_pct,
item_ind
FROM ABC.a_cmpnt_w
WHERE b_item_typ_cd IN ('A','U','I')
ORDER BY DECODE(b_item_typ_cd,'A','A'||b_item_typ_cd,
'U','B'||b_item_typ_cd,
'C'||b_item_typ_cd);
Query 2:
SELECT a_name,
b_item_typ_cd,
item_num,
a_m_name,
DECODE(RTRIM(LTRIM(t_clasfn_cd)),NULL,NULL,
‘X’|| t_clasfn_cd) t_clasfn_cd,
in_splt_pct,
item_ind
FROM ABC.a_cmpnt_w
WHERE b_item_typ_cd IN ('U','I')
ORDER BY DECODE(b_item_typ_cd,'U','A'||b_item_typ_cd,
'B'||b_item_typ_cd);
Query 3:
SELECT a.item_num
FROM ABC.item a, ABC.X2_PRDT_LN b
WHERE a. PRDT_LN_CD= b. PRDT_LN_CD
AND b. t_clasfn_cd = t_clasfn_cd
so I want to write a single query .
Thanks.

Answer 1

Try this..
SELECT a_name,
b_item_typ_cd,
item_num,
a_m_name,
DECODE(RTRIM(LTRIM(t_clasfn_cd)),NULL,NULL,
‘X’|| t_clasfn_cd) t_clasfn_cd,
in_splt_pct,
item_ind
FROM ABC.a_cmpnt_w
WHERE b_item_typ_cd IN ('A','U','I')
--ORDER BY DECODE(b_item_typ_cd,'A','A'||b_item_typ_cd,'U','B'||b_item_typ_cd,'C'||b_item_typ_cd);
union all
SELECT a_name,
b_item_typ_cd,
item_num,
a_m_name,
DECODE(RTRIM(LTRIM(t_clasfn_cd)),NULL,NULL,
‘X’|| t_clasfn_cd) t_clasfn_cd,
in_splt_pct,
item_ind
FROM ABC.a_cmpnt_w
WHERE b_item_typ_cd IN ('U','I')
--ORDER BY DECODE(b_item_typ_cd,'U','A'||b_item_typ_cd,'B'||b_item_typ_cd);
union all
SELECT NULL,NULL,a.item_num,NULL,NULL,NULL,NULL
FROM ABC.item a, ABC.X2_PRDT_LN b
WHERE a. PRDT_LN_CD= b. PRDT_LN_CD
AND b. t_clasfn_cd = t_clasfn_cd)U have to remove the order by clause from indiviual queruies,but u can use order by at the end..
And for union u must have same no of columns in each query..
Regards
Umesh