Default database for SAP BW

[Former Member]

Hello experts,

I am new to SAP BW & HANA. This could be a very basic question.

In SAP BW, on its own, where does the data get stored when you do an ETL from other SAP/non SAP systems? Am not talking about the data targets like infocube, DSOs .. but instead where does these data targets get stored? Is it oracle? or is this database a customer choosen one during the client installation? or does SAP give a default database?

This question has come into my mind when am trying to understand the concept of migrating or building SAP BW on HANA.

HANA is an in memory database and the current BW systems (7.3 or above) can be put on the new HANA database... If this is the case, are we saying we are potentially changing the database of SAP BW from Oracle (if my above perception is true) to HANA?

Also while going through some material related to HANA, I understood that below are the options available to introduce HANA in an organisation

1. Option 1 - New BW Instance - Creating a totally new BW instance, and connect it to the SAP HANA database -> Does this mean take license of a BW system and choose the database as HANA/
2. Option 2 - Change BW's DB -> Does this mean change the existing database of BW from ORacle (or whatever it is ) to HANA?
3. Option 3 - Run in parallel -> Does this mean, we will have two BW systems - One exisiting BW insance which runs on the existing database and the other new BW instance which runs on the new HANA database. But this approach has redundancy in data?

Any little help is very much appreciated.

Thank you

[Former Member · Accepted solution]

Hi Sandi,

SAP BW is like any other Application that needs a Database to store data

Depending on the organization that is using the SAP BW system one of the multiple supported Databases(Oracle, SQL Server, Sybase etc..) is chosen for the setup

Now that SAP has its own RDBMS HANA, SAP suggests to use HANA for various benefits of the customer

Quick feedback on your points:

Option1: If a customer is implementing SAP BW for the first time they could directly setup SAP BW with Database on HANA(need to buy license for HANA)

Option2: Any SAP BW Database on non HANA Database could be migrated to HANA

Option3: The data from non HANA RDBMS of SAP BW can be replicated to a HANA Database and SAP transactions can be repointed to this data from HANA instead of the current non HANA Database. So here you have 2 Database's not 2 SAP BW systems

More information is available under the below SCN link

http://scn.sap.com/community/bw-hana/faq/content

Good starting point would be to read the below blog and refer to other documents under this blog

http://scn.sap.com/docs/DOC-59790

Hope it helps

Sunil

[Former Member · Accepted solution]

Thank You Sunil for your reply. That was really helpful and this is what am exactly looking for

Also can you please clarify one more thing On option 3 - When we replicate the data from non-HANA to HANA in the same BW instance....  is it on daily basis? I visualize this as shown below. Please let me know if my understanding is correct.

If this is the case, why should we really go for this option? Is it easy when compared to option 2 i.e replace non HANA with HANA?

Thanks in advance.

[Former Member · Accepted solution]

Hi Sandi,

The SAP SLT Replication from NON HANA to HANA Database can be scheduled based on the needs, example itcan be scheduled for every few hours or real time for continuous replication

Here is the SLT Blog that can help you understand this feature of HANA, refer to the documents under this Blog that are quite useful, your visual is accurate

http://scn.sap.com/community/replication-server

Regarding your question: Option2 is for customers who can move the Database to HANA completely

Option3 is an option that is useful for customers who would need to spend some time on HANA while operating on their current RDBMS, HANA being a new solution customers will need time for their resources to adapt, and migrate to complete HANA at a later stage

Hope this helps

Sunil

[Former Member · Accepted solution]

Sunil,

Thanks for your time and the clarification provided