OLAP considerations

Question

So I was asked to look into OLAP, and generating cubes for a reporting tool. I kind of came accross documents at both ends of the difficulty spectrum. Could someone tell me if I'm overlooking anything, because my initial attempts at generating cubes support the "simple" end.
The "difficult" instructions lead me to believe that in 10g there must be some default setup already in place, because the ROLLUP and CUBE functions already work.
Are there scalability issues that need looking into, or are ROLLUP & CUBE just variations on GROUP BY, and so the same issues apply?
Simple instructions:
http://oraclebizint.wordpress.com/2007/08/30/oracle-10g11g-olap-cube-and-rollup/
Difficult instructions:
http://www.dbazine.com/datawarehouse/dw-articles/rittman7
My test data & queries:
create table olap_test
(product varchar2(20),
color varchar2(10),
num_ordered number(6)
insert into olap_test values ('gum','blue',25);
insert into olap_test values ('gum','green',30);
insert into olap_test values ('chocolate','dark',1);
insert into olap_test values ('soda','yellow',1);
insert into olap_test values ('soda','yellow',1);
insert into olap_test values ('soda','white',1);
select product, color , sum (num_ordered)
from olap_test
group by rollup (product),
         rollup (product,color);
select product, color, sum (num_ordered)
from olap_test
group by cube (product),
         cube (product,color);Thanks,
--=Chuck

Answer 1

There is an OLAP option to the database. For an introduction to that option you may want to check out this information:
[OLAP and Data Mining|http://download.oracle.com/docs/cd/B19306_01/server.102/b14223/bi.htm#sthref1954]
Brief Description:
The OLAP OptionThe OLAP option of the Oracle Database includes the following components:
* The OLAP analytic engine, which supports the selection and rapid calculation of multidimensional data within the Oracle Database.
* Analytic workspaces, which store data in a multidimensional format where it can be manipulated by the OLAP engine.
* Analytic Workspace Manager, a graphical user interface for creating and maintaining analytic workspaces.
* OLAP Worksheet, an interactive environment for executing OLAP DML, the data definition and manipulation language for interacting with analytic workspaces.
* Interfaces for developing OLAP applications in SQL and Java.
* OLAP Catalog, the metadata repository which represents a star schema as a logical cube. The OLAP Catalog enables OLAP applications to access relational data.
>
The ROLLUP and CUBE options are detailed in:
[SQL for Aggregation in Data Warehouses|http://download.oracle.com/docs/cd/B19306_01/server.102/b14223/aggreg.htm#i1007462]
My understanding is that the OLAP option would be used in cases where you have significant quantities of data, or the answers to the questions are not known at time of coding (hence negates the ability of materialized views).
However in my experiences thus far all the capabilities identified in [SQL for Aggregation in Data Warehouses|http://download.oracle.com/docs/cd/B19306_01/server.102/b14223/aggreg.htm#i1007462] has been able to answer all the questions I have needed.