Joining query with single row result

Question

dear all,
i have two tables
create table item(item_id number primary key,
item_desc varchar2(200));
create table item_properties(item_id number references item(item_id),
property_name varchar2(20),
property_value varchar2(100));i insert the following records
insert into items values(1,'CPU');
insert into item_properties values(1,'RAM','2gb');
insert into item_properties values(1,'PROCESSOR','2ghz');
insert into item_properties values(1,'HARDDISK','2ghz');
commit;now i want a query which produce the following results
item_id      RAM      PROCESSOR         HARDDISK
1              2gb        2ghz              2TBHow to generate this result?
i have create a query but it generate multiple rows, instead i need in a single row like above.
select i.item_id,p.property_value from items i , item_properties p
where i.item_id=p.item_id and i.item_id=1;Kind thanks.
Edited by: Maahjoor on May 7, 2013 12:22 AM

Answer 1

select i.item_id,
       max(decode(p.property_name,'RAM',p.property_value)) ram,
       max(decode(p.property_name,'PROCESSOR',p.property_value)) processor,
       max(decode(p.property_name,'HARDDISK',p.property_value)) hd
from items i , item_properties p
where i.item_id=p.item_id
and i.item_id=1
group by i.item_id;Or pivot in 11g
with details as
select i.item_id,p.property_name,p.property_value
from item i , item_properties p
where i.item_id=p.item_id
and i.item_id=1
select *
from details
pivot
   max(property_value) for property_name in ('RAM','PROCESSOR','HARDISK')
);Edited by: jeneesh on May 7, 2013 1:04 PM