All along this journey, we've been using the Block Storage Option BSO database architecture.. You see, the BSO architecture used by Essbase is the original database architecture as the b
Trang 1Essbase Analytics Option
Welcome to the exciting world of Essbase Analytics known as the Aggregate Storage Option (ASO)
In the first nine chapters of this book, we have taken you from being a competent IT professional that is an Essbase novice, to that same competent IT professional who
is now a capable Essbase programmer/administrator as well All along this journey, we've been using the Block Storage Option (BSO) database architecture
We have presented all of the instructions, teachings, and examples based on the
BSO, in Essbase All of the efficient methods of processing, performance tuning,
and database design have been geared towards using the BSO In fact, prior to
Essbase version 7.x, your only option was the use of the BSO architecture for
building Essbase applications
Well, now you're ready to take everything one step further You see, the BSO
architecture used by Essbase is the original database architecture as the behind the
scenes method of data storage in an Essbase database Remember, we have already
discussed that the block construction can be conceptually compared to a Rubik's
Cube for how the data is stored in the cells of a data block, like the cells of color on
a Rubik's Cube The ASO method is entirely different
Let's learn all about the ASO which is now also used to store data in an Essbase
database We will learn exactly what ASO is, how it works, and when to use
ASO instead of BSO We will explain the use of the special industry standard
multidimensional data query language known as MDX that is employed by Essbase, and is particularly effective with ASO Finally, we'll go over the pros and cons of
ASO and BSO
Trang 2What is ASO
ASO is Essbase's alternative to the sometimes cumbersome BSO method of storing
data in an Essbase database In fact, it is BSO that is exactly what makes Essbase
a superior OLAP analytical tool but it is also the BSO that can occasionally be a
detriment to the level of system performance demanded in today's business world
In a BSO database, all data is stored, except for dynamically calculated members
All data consolidations and parent-child relationships in the database outline are
stored as well While the block storage method is quite efficient from a data to size
ratio perspective, a BSO database can require large amounts of overhead to deliver
the retrieval performance demanded by the business customer
The ASO database efficiently stores not only zero level data, but can also store
aggregated hierarchical data with the understandings that stored hierarchies can
only have the no-consolidation (~) or the addition (+) operator assigned to them
and the no-consolidation (~) operator can only be used underneath Label Only
members Outline member consolidations are performed on the fly using dynamic
calculations and only at the time of the request for data This is the main reason
why ASO is a valuable option worth consideration when building an Essbase
system for your customer
Because of the simplified levels of data stored in the ASO database, a more simplified method of storing the physical data on the disk can also be used It is this simplified storage method which can help result in higher performance for the customer
Your choice of one database type over the other will always depend on balancing
the customer's needs with the server's physical capabilities, along with the volume
of data These factors must be given equal consideration
Creating an aggregate storage
Application|Database
Believe it or not, creating an ASO Essbase application and database is as easy as
creating a BSO application and database In case you have forgotten how to do it
from the information we've given you in earlier chapters, all you need to do is
follow these simple steps:
Trang 31 Right-click on the server name in your EAS console for the server
on which you want to create your ASO application
2 Select Create application | Using aggregate storage as shown in
the following screenshot:
3 Click on Using aggregate storage and that's it The rest of the steps are
easy to follow and basically the same as for a BSO application
To create an ASO application and database, you follow virtually the same steps
as you do to create a BSO application and database However, there are some
important differences, and here we list a few:
• A BSO database outline can be converted into an Aggregate Storage database outline, but an Aggregate Storage database outline cannot be converted into
a Block Storage database outline
Trang 4Steps to convert a BSO application into an ASO application:
° Open the BSO outline that you wish to convert, select the Essbase
database and click on the File | Wizards | Aggregate Storage
Outline Conversion option You will see the first screen Select
Source Outline The source of the outline can be in a file system
or on the Essbase Server In this case, we have selected the OTL
from the Essbase Server and then click Next as shown in the
following screenshot:
° In the Next screen, the conversion wizard will verify the
conversion and display a message that the conversion has
completed successfully Click Next.
° Here, Essbase prompts you to select the destination of the ASO
outline If you have not yet created an ASO application, you
can click on the Create Aggregate Storage Application on the
bottom-right corner of the screen as shown in the next screenshot:
Trang 5Enter the Application and the Database name and click on OK Your new
ASO application is created, now click on Finish Your BSO application is now
converted into an ASO application You may still need to tweak the ASO
application settings and outline members to be the best fit for your needs
• In an ASO database, all dimensions are Sparse so there is no need to
try to determine the best Dense/Sparse settings as you would do with
a BSO database
• Although Essbase recommends that you only have one Essbase database
in an Essbase application, you can create more than one database per
application when you are using the BSO When you create an ASO
application, Essbase will only allow one database per application
There is quite a bit to know about ASO but have no fear, with all that you know about Essbase and how to design and build an Essbase system, it will seem easy for you
Keep reading for more valuable information on the ASO for things like, when it is
a good time to use ASO, or how do you query ASO databases effectively, or even