-
SAP COMMUNITY NETWORK 2010 SAP AG 1
Practitioner Perspective, Modelling HANA vs BW7
Applies to: Document is applicable to all systems on SAP HANA
Platform.
Summary This document provides an introductory and practical
overview of HANA. It will provide a conceptual comparison as well
as practical illustration.
Author(s): Benedict Yong Teng Xiang Created on: 1 December
2014
Author Bio Benedict Yong is a Certified SAP BI Consultant, and
practitioner of Business Intelligence (BI) and Enterprise Asset
Management (EAM).
He holds a Masters in ERP (Finance focus), Bachelor of
Management (Australia) and a Diploma in Business InfoTech
(Singapore). He is familiar with the Consulting and Support
environments, with his various Project Lead & Consultant
roles.
He is situated in Singapore and is bilingual in English and
Mandarin. He can be contacted at [email protected].
Note: credits given on the last page.
-
Practitioner Perspective, Modelling HANA vs BW7
SAP COMMUNITY NETWORK 2010 SAP AG 2
Table of Contents Introduction
...................................................................................................................................................
3 Definitions
.....................................................................................................................................................
4
What is HANA?
.........................................................................................................................................
4 What are the benefits of HANA?
................................................................................................................
6 What is BW-on-HANA?
..............................................................................................................................
7 What are the benefits of BW-on-HANA?
....................................................................................................
8
HANA Modelling step-thru
.............................................................................................................................
9 HANA Modelling Concept
..........................................................................................................................
9 Attribute View
..........................................................................................................................................
10 Analysis View
..........................................................................................................................................
11 Calculation View
......................................................................................................................................
14 HANA Modelling vs BW7 Modelling
.........................................................................................................
20
Bridging HANA into BW7
.............................................................................................................................
21 TransientProvider using HANA Model
......................................................................................................
22 VirtualProvider using HANA Model
..........................................................................................................
23
Bringing together HANA and BW7 Data
......................................................................................................
26 Getting Data at its Source: HANA Live
........................................................................................................
30 Conclusion
..................................................................................................................................................
31 Credits and Content Sources
......................................................................................................................
32
-
Practitioner Perspective, Modelling HANA vs BW7
SAP COMMUNITY NETWORK 2010 SAP AG 3
Introduction What is HANA? Despite all the buzz and media
attentions given to HANA, it only brings more confusion as the
definition continues to expand day-by-day. I liken HANA as a
proverbial elephant that has many version of truths for those have
not seen it firsthand. This paper seeks to provide introductory and
practical overview of HANA.
Apart from answering what is HANA, it also seeks to provide
answers to the following questions: How is it different from
traditional database? Can or should BW and HANA co-exist? How does
it impact BI architecturing with the inclusion of HANA
technology?
-
Practitioner Perspective, Modelling HANA vs BW7
SAP COMMUNITY NETWORK 2010 SAP AG 4
Definitions
What is HANA? The term HANA is an acronym for "High-Performance
Analytic Appliance.
SAP defines HANA as a modern in-memory platform that is
deployable as an on-premise appliance or in the cloud. As an
appliance, SAP HANA combines software components from SAP optimized
on proven hardware provided by SAPs hardware partners.
In short, HANA is SAP in-memory solution. Its a database. You
can run BW on it or you can run ERP (or other Business Suites) on
it.
The following illustrates the multiple facets of HANA
technology:
(image credits from SAP, additional anotation by author)
But in what sense is an in-memory database difference from a
traditional database?
-
Practitioner Perspective, Modelling HANA vs BW7
SAP COMMUNITY NETWORK 2010 SAP AG 5
SAP HANA holds majority of its data in the memory for high
performance. However, it still uses persistent storage to provide a
fallback in case of failure. SAP promises a compliance to the ACID
(Atomicity, Consistency, Isolation, Durability) expectation of
traditional databases.
During normal database operation, data is automatically saved
from memory to disk at regular intervals called savepoints. If a
failure occurs, for example a power failure, the database will
restarted in the same manner as any disk-based database, and it is
returned to its last consistent state by replaying the redo log
since the last savepoint.
SAP recommends that the Log file volume to be 3x 5x of the
Memory for HANA.
Within the HANA box, we can choose to load all tables into it or
selective (because the HANA box will still have a size limit). At
startup, all row-based table are fully loaded, but column-based
table are loaded on-demand (default setting).
SAP HANA is not only just an innovative technology, it is
packaged with additional tools (such as HANA Studio for modelling,
HANA appliances for specific business requirements)
-
Practitioner Perspective, Modelling HANA vs BW7
SAP COMMUNITY NETWORK 2010 SAP AG 6
What are the benefits of HANA? The speed benefit of HANA ranges
in the thousands from 100x to 100,000x. At such performance
improvement, organization can experience enablement that would
never have been possible.
The performance of HANA is achieve through a couple of factors:
(details on the individual factors can be found in
www.saphana.com)
-
Practitioner Perspective, Modelling HANA vs BW7
SAP COMMUNITY NETWORK 2010 SAP AG 7
What is BW-on-HANA? As mentioned earlier, HANA is a database
that BW or ERP can choose to run on. It is a logical step to move
BW into HANA, due to its speed performance and scalable and agile
modeling. From personal experience, BEx reports can have an
improvement of 500x 3000x.
Typical BW
BW-on-HANA, means the whole BW server is running in-memory
(including BEx)
-
Practitioner Perspective, Modelling HANA vs BW7
SAP COMMUNITY NETWORK 2010 SAP AG 8
What are the benefits of BW-on-HANA? We have two options to
leverage on HANAs high performance:
1) Using BW base on the optimized cubes no modelling need, cubes
are migrated 2) Using BW with HANA Modelling options.
HANA optimized infocubes have a different structure with
traditional BW7 infocubes. InfoCubes in BW are modeled using the
BW-extended star schema with 2 fact tables (an E table with
read-optimized partitioning, and an F table with
write/delete-optimized partitioning), Dimension tables grouping
sets of characteristics, and shared Master Data tables. This schema
is optimized for classic RDBMS technology. With HANA technology,
the schema can be simplified to one fact table (HANA can perform
read, write and delete operations equally fast on this layout)
joined directly to the Master Data tables.
HANA optimized infocubes eliminate unnecessary joins and tables
bringing in better performance. No modelling is needed.
However, to harness the power of on-the-fly in-memory advantage,
we need to apply HANA modelling. HANA modelling comprises of views,
these views generate real-time SQL statements behind the scene. The
advantage is in its non-persistency nature: data is read and not
staged, this data-modelling agility is coupled with native HANA DB
in-memory speed.
-
Practitioner Perspective, Modelling HANA vs BW7
SAP COMMUNITY NETWORK 2010 SAP AG 9
HANA Modelling step-thru
HANA Modelling Concept HANA Modelling uses 3 information views,
namely:
(1) Attribute View (2) Analysis View (3) Calculation View
The information views from HANA Modelling draw parallel to BW7
concept of MasterData and InfoCube. At the Attribute View level, we
can combine several MasterData tables and appoint a primary key. At
this stage, we can do Master Data reporting. At the Analysis View
level, we can combine several Transaction Data tables as the
foundation, and enrich it with Attribute View. At this stage, we
can already achieve analytical reporting. If more complex scenario
exist, such as merging two infocubes, we can create a Calculation
View.
In pages to come, we will explain the HANA modelling process in
greater details. It will helps to explain what is HANA modelling,
but it will not be suffice to explain how to do HANA modelling.
-
Practitioner Perspective, Modelling HANA vs BW7
SAP COMMUNITY NETWORK 2010 SAP AG 10
Attribute View It is used for Master Data Modeling
Can be used to join two or more master data tables (eg MARA,
MARC, MAKT, MBEW) No measures, only attributes
Attribute View modelling is broken down into 2 steps: At the
Data Foundation stage, we can join master tables At the Semantics
stage, we can set the details of the final columns
HANA Studio allows a sample data preview for the first 200
rows:
-
Practitioner Perspective, Modelling HANA vs BW7
SAP COMMUNITY NETWORK 2010 SAP AG 11
Analysis View It represents an OLAP View with a Star Schema
including measures and attributes. Represents an OLAP View with a
Star Schema including measures and attributes.
Can be used to join two or more transaction data tables (eg
VBRK, VBRK) as well as master data tables and Attribute Views
Includes a Data Foundation based on a Fact Table with measures.
Can be used for OLAP Analysis, typically within one functional
area
Analysis View modelling is broken down into 3 steps: At the Data
Foundation stage, we can join transaction tables At the Logical
Join stage, we can link the Data Foundation with Attribute Views At
the Semantics stage, we can set the details of the final
columns
At the Data Foundation pane, we can insert the transaction
tables and perform joining.
-
Practitioner Perspective, Modelling HANA vs BW7
SAP COMMUNITY NETWORK 2010 SAP AG 12
At the Logical Join pane, we can see the transaction tables are
represented as Data Foundation. We can perform joining with
Attribute View.
At the Semantics pane, we can set the details of the final
columns.
-
Practitioner Perspective, Modelling HANA vs BW7
SAP COMMUNITY NETWORK 2010 SAP AG 13
HANA Studio allows a sample data preview for the first 200
rows:
HANA Studio allows the sample data preview to be in charts:
-
Practitioner Perspective, Modelling HANA vs BW7
SAP COMMUNITY NETWORK 2010 SAP AG 14
Calculation View It is used for Advanced Modeling, for instance
cross-cube analysis or flexible joining
Calculation Views are used to address complex business
scenarios. They are created using attribute views, analytic views
and tables.
It can be created directly using the SQL (Script) editor, or
using the standard Information View Modelling
Calculated View modelling is broken down into 4 steps
(minimally): Projection where Analytic Views or Attribute Views are
selected Combination the individual Projections can be combined
(Union or Join) Aggregation grouping of lines with similar keys. At
aggregation, Attribute View can be added Semantics settings on the
final columns
In our case, we can have a fabricated taxation scenario. In our
taxation analysis, we need to compute the total taxation amount
where New York has a 15% Goods/Services Tax and Texas has a 7%
Goods/Services Tax. In Calculation View Modelling, we can do Select
(aka Projection) for New York and compute the amount. Likewise for
Texas. Finally, perform a Union
-
Practitioner Perspective, Modelling HANA vs BW7
SAP COMMUNITY NETWORK 2010 SAP AG 15
We start by pulling in the Projection Task into the Scenario
Pane. After defining the Projection Task, we will drag in the Union
Task.
During the definition of Projection (Selection), we can choose
what column to pick and filter off rows. In our case, we need to
filter State = New York.
-
Practitioner Perspective, Modelling HANA vs BW7
SAP COMMUNITY NETWORK 2010 SAP AG 16
In the Projection Task, we can define new columns. In our case,
we need to create the computed State_Tax as (Amount Sold X
15%).
In the Union Task, we can map the output fields from the
incoming fields (from the Projection).
-
Practitioner Perspective, Modelling HANA vs BW7
SAP COMMUNITY NETWORK 2010 SAP AG 17
HANA Studio allows a sample data preview for the first 200
rows:
-
Practitioner Perspective, Modelling HANA vs BW7
SAP COMMUNITY NETWORK 2010 SAP AG 18
Next we are going to include the next leg for State = Texas and
include it into the Union mapping.
HANA Studio allows a sample data preview for the first 200
rows:
-
Practitioner Perspective, Modelling HANA vs BW7
SAP COMMUNITY NETWORK 2010 SAP AG 19
Alternatively, a Calculated View can be created base on
scripting (instead of modelling panels).
-
Practitioner Perspective, Modelling HANA vs BW7
SAP COMMUNITY NETWORK 2010 SAP AG 20
HANA Modelling vs BW7 Modelling BW7 Modelling is based on
persistent data storage hence will have loading tasks such as
Infopackage, DTP. HANA Modelling based on in-memory data storage
hence will focus more querying tasks such Join/Union, Aggregation,
Projection (equivalent to SQL Select / Where). Remodeling is a
topic organization shun due to its risk and effort for data
migration. However, in an ever-changing business environment,
changing business strategies entails changing reporting and
remodeling of datasources. In BW7, the Remodelling Toolkit helps
cushion of quite a large portion of the pain but migratory effort
still exist at a smaller scale. With HANA Modelling having
transient InfoProviders, it rids us the hassle of post-remodelling
migration, cutting short deployment time, allowing agile response.
Do note that the developer will still need to re-publish, activate
the infocube when the model gets updated.
Revisiting the earlier Calculation View Tax Scenario, HANA
Modelling makes development flow with greater ease. Using BW7
Modelling for the same scenario, we need to have two more cubes to
split the data into two different Taxation States for individual
processing and union them back again with a MultiProvider. Not to
mention, the Process Chain needed to cater for the additional
modelling steps. For discussion purposes, we can have a quick-fix
by using a restricted key figure in BEx. But what if the criteria
gets more complicated, how would BW7 Data flow handle and how would
HANA Modeler handle? In HANA Modeler, we are allowed to create
multiple Projections (SQL Select / Where) and in each isolated
Projections we can tweak the flow of that particular set of data.
Eventually when we are ready, we can merge those Projections with a
Join/Union task. For those who are SQL purist, they can query their
way into a Calculation View. Such flexibility and scalability will
be very difficult for any persistent InfoProvider to rival.
BW7 Data flow HANA Modeler
-
Practitioner Perspective, Modelling HANA vs BW7
SAP COMMUNITY NETWORK 2010 SAP AG 21
Bridging HANA into BW7 The HANA information model can be
utilized by BEx, in one of the two ways: 1) TransientProvider using
HANA Model 2) VirtualProvider using HANA Model
From our earlier HANA Modelling, we have created 3 type of
Information Views. We can use these for illustrating how HANA data
can be access by BW (specifically BEx).
-
Practitioner Perspective, Modelling HANA vs BW7
SAP COMMUNITY NETWORK 2010 SAP AG 22
TransientProvider using HANA Model For the above option, we need
to use the BW7 transaction RSDD_HM_PUBLISH. This will export HANA
Model to BW7 and make it available for BEx. It is optional to
create specific infoobject for the published fields.
-
Practitioner Perspective, Modelling HANA vs BW7
SAP COMMUNITY NETWORK 2010 SAP AG 23
VirtualProvider using HANA Model For the above option, we need
to use the BW7 Workbench to create a VirtualProvider with the 4th
option VirtualProvider Based on HANA Model.
-
Practitioner Perspective, Modelling HANA vs BW7
SAP COMMUNITY NETWORK 2010 SAP AG 24
Package and Information Views has to be selected.
-
Practitioner Perspective, Modelling HANA vs BW7
SAP COMMUNITY NETWORK 2010 SAP AG 25
Individual fields from the information view has to be assigned
with a BW infoobject.
-
Practitioner Perspective, Modelling HANA vs BW7
SAP COMMUNITY NETWORK 2010 SAP AG 26
Bringing together HANA and BW7 Data
HANA Modelling bring in a very important benefits to the BI
space, providing additional flexibility for discovery and agile
response. However, the need for traditional standardization and
structuring is also necessary. The use of HANA and BW7 Modelling
depend on specific business scenarios.
Integrating HANA data with BW7 can be achieved with one of the 4
methods: Using BW7 MultiProvider in conjunction with
VirtualProvider (HANA Model based) Using BW7 CompositeProvider in
conjunction with TransientProvider Using multisource Universe Using
merge queries in Webi
-
Practitioner Perspective, Modelling HANA vs BW7
SAP COMMUNITY NETWORK 2010 SAP AG 27
-
Practitioner Perspective, Modelling HANA vs BW7
SAP COMMUNITY NETWORK 2010 SAP AG 28
-
Practitioner Perspective, Modelling HANA vs BW7
SAP COMMUNITY NETWORK 2010 SAP AG 29
-
Practitioner Perspective, Modelling HANA vs BW7
SAP COMMUNITY NETWORK 2010 SAP AG 30
Getting Data at its Source: HANA Live As mentioned earlier, HANA
is a database. We can run BW on HANA, we can also run ERP on HANA
(aka Business Suite on HANA). The clear advantage of this is, we
are nearer to the data lesser overheads, more options. In the past,
having an OLAP in an OLTP is not recommended due to resource
constraints. HANA, however, has removed this hurdle.
Once again the question, should we eliminate BW? The answer: it
depends. I can think of one scenario that BW is relevant. Imagine a
company archives its ERP tables annually will not be able to
perform multi-year sales analysis directly at its source; BW on the
other hand, being a staging data warehouse, will contain summarized
multiyear information.
-
Practitioner Perspective, Modelling HANA vs BW7
SAP COMMUNITY NETWORK 2010 SAP AG 31
Conclusion In the past, ERP is used as a competitive advantage
for enterprise-wide effective consolidation. As ERP is becomes a
norm for large enterprise, as well as, medium; this advantage has
been diluted. The new advantage resides in the data that ERP has
collected. With the inclusion of HANA and Businessobjects, the BI
landscape is not limited to only Traditional BW7 Modelling and BEx
reporting. We are now presented with unprecedented versatility. For
instance, we have options between Webi broadcasting capabilities
versus traditional EP, BW MultiProvider versus Webi merge queries,
BW workspace versus Webi ExcelProvider, and so on. Our challenge
now, is how to harness relevant and applicable information that has
long been left out in our ERP treasure trove. The emergence of ERP
on HANA and HANA Live beautifully brings Analytics back to SAP ERP
--- not as a peripheral extension but an intrinsic business
process. We should come to the understanding that Analytics is the
business process of business processes --- all business processes
have KPI and needs to be measured.
-
Practitioner Perspective, Modelling HANA vs BW7
SAP COMMUNITY NETWORK 2010 SAP AG 32
Credits and Content Sources 1. SAP HANA Portal
www.saphana.com 2. SAP HANA Technical Operations Manual
help.sap.com/hana/sap_hana_technical_operations_manual_en.pdf