To Join 9 Select Statements

Question

Hi All,
I have 9 select Statements,i can combine these queries by 'UNION' to get the result....but the process will be tedious.
Is there any other option to do the same in a easy way.
Example :
SELECT ecv.creation_date "Initiation Date",
eceb.c_ext_attr1 "REPORTING PERSON",
eceb.c_ext_attr2 INITIATOR,
eceb.c_ext_attr3 "REPORTING PERSON TITLE",
eceb.d_ext_attr2 "AWARE DATE",
eceb.c_ext_attr4 TELEPHONE
FROM eng_changes_v ecv,
eng_changes_ext_b eceb
WHERE ecv.change_id = eceb.change_id
AND ecv.change_notice = 'COM-10034'
AND attr_group_id = 266;
UNION
SELECT eceb.c_ext_attr2 TYPE,
eceb.c_ext_attr3 INSTITUTION,
eceb.c_ext_attr4 TERRITORY,
eceb.c_ext_attr5 "CUSTOMER NAME",
eceb.c_ext_attr6 TITLE,
eceb.c_ext_attr7 ADDRESS,
eceb.c_ext_attr8 "ADDRESS 2",
eceb.c_ext_attr9 CITY,
eceb.c_ext_attr10 STATE,
eceb.n_ext_attr1 ZIP,
eceb.c_ext_attr11 COUNTRY,
eceb.c_ext_attr12 TELEPHONE,
eceb.c_ext_attr13 FAX
FROM eng_changes_v ecv,
eng_changes_ext_b eceb
WHERE ecv.change_id = eceb.change_id
AND ecv.change_notice = 'COM-10034'
AND attr_group_id = 267;
In this fashion i have 9 select statements.
Thanks in advance!
Ramya

Answer 1

Well, this is not the silly EAV model …
but it does look as something that has been slightly abused on the dynamic/generic side.
You certainly do not want to UNION … it wouldn’t make sense anyway.
Think of your ATTR_GROUP_ID as identifiers of what could have been real tables
(dependents of ENG_CHANGES_V):
create view could_be_table_266 as
select change_id
      ,c_ext_attr1  REPORTING_PERSON
      ,c_ext_attr2  INITIATOR
      ,c_ext_attr3  REPORTING_PERSON_TITLE
      ,d_ext_attr2  AWARE_DATE
      ,c_ext_attr4  TELEPHONE
from   eng_changes_ext_b
where  attr_group_id = 266
create view could_be_table_267 as
select change_id
      ,c_ext_attr2   TYPE
      ,c_ext_attr3   INSTITUTION
      ,c_ext_attr4   TERRITORY
      ,c_ext_attr5   CUSTOMER NAME
      ,c_ext_attr6   TITLE
      ,c_ext_attr7   ADDRESS
      ,c_ext_attr8   ADDRESS_2
      ,c_ext_attr9   CITY
      ,c_ext_attr10  STATE
      ,n_ext_attr1   ZIP
      ,c_ext_attr11  COUNTRY
      ,c_ext_attr12  TELEPHONE
      ,c_ext_attr13  FAX
from   eng_changes_ext_b
where  attr_group_id = 267
Then join using your knowledge of what the “logical” relationship between these table would be … likely
select <columns_you_need_from x>
      ,<columns_you_need_from a>
      ,<columns_you_need_from b>
from   eng_changes_v       x
      ,could_be_table_266  a
      ,could_be_table_267  b
where  x.change_id = a.change_id (+)
and    x.change_id = b.change_id (+)
and    x.change_notice = 'COM-10034'
Using column names like "REPORTING PERSON" rather than REPORTING_PERSON is just a pain in the …
What column headings one wants in a report/screen doesn’t have to drive the names of select list items in SQL.
TYPE is likely not a good name … reserved word