Data migration SAP BW to HANA

[Former Member]

Hello all

I'm developing a SAP HANA XS application which displays data from a SAP BW query.

At the moment I'm looking for a method / best practice to retrieve these data inside the HANA XS application. Possibilities are:

- to transfer the back-end data into HANA tables and to rebuild the BW logic in HANA Views/Server-side JavaScript

- to replicate the BW Query output in HANA tables

- to retrieve the data from BW and to use HANA XS only as front-end (I think, this is not recommended because it doesn't make use of the HANA optimization methods)

Do you know data migration tools / interfaces for these options?

Thanks!

Christoph

[AtulKumarJain · Accepted solution]

Hi Christoph,

You can replicate data using below method

ETL based,Trigger based,Log Based replication.

Please check below link for more information.

http://help.sap.com/download/multimedia/ebooks/ec/SAPHANAOverviewofDataReplication/story_content/ext...

http://www.saphana.com/servlet/JiveServlet/previewBody/1311-102-1-1730/Master%20Guide.pdf

Best Regards,

Atul

[patrick_winkler]

Hello,

you can publish the BW data as HANA models in two ways; importing via the HANA studio or exporting via the BW backend

http://help.sap.com/saphelp_nw75/helpdata/en/17/8745cfaeed428eb1fa6d86ad2e40e6/content.htm?frameset=...

I would recommend the backend approach. There you can expose BW Queries as HANA views, the HANA views are part of the BW lifecycle and automatically adjusted. They are then also part of the BW transport.

General information:

http://help.sap.com/saphelp_nw75/helpdata/en/66/33d851345c4770bd4e523701b9f5b0/content.htm?frameset=...

BW Query as HANA view:

http://help.sap.com/saphelp_nw75/helpdata/en/c4/70990abfce4796aacf7a41a27fedcc/content.htm?frameset=...

Regards,

  Patrick

[former_member184768]

Hi Christoph,

May be I missed one point, but can you please confirm that you have a SEPARATE SAP BW system on a database which is NOT HANA. If so, you can deploy any of the methods suggested above.

But if you already have BW on the SAME HANA server and wish to use XS application only for the front end reporting, then you can publish your BW models to HANA and can consume them in XS application.

Regards,

Ravi

[Former Member]

Hi Ravindra,

I already have a BW-on-HANA system. Indeed, I now want to use HANA XS only as a frontend, to publish the results of BW queries using SAPUI5 elements.

How can I publish my BW models to HANA?

I found this SAP note here:

Note 1764251 - Documentation- Importing BW Models in SAP HANA Modeler

My question is: Are the imported data in HANA automatically updated when the BW model changes?

Or do I need the "Trigger-based replication" which Atul Jain mentioned in this case?

Thanks!

Christoph

[vivekbhoj]

Hi Christoph,

If you import BW models into HANA, then HANA creates Views based on type of your BW Model.

Analytic View for IMDSO, Calculation View for In Memory InfoCube.

If i talk about IMDSO, then in this case for Analytic View created in HANA, DSO Active table acts as Fact Table and  so if new data will come into the Active table, it will be automatically reflected in the View.

Regards,

Vivek

[former_member184768]

Hi Christoph,

Christoph Wagner wrote:
My question is: Are the imported data in HANA automatically updated when the BW model changes?
Or do I need the "Trigger-based replication" which Atul Jain mentioned in this case?
Thanks!
Christoph

In the current BW on HANA revision, you need to REIMPORT the BW objects once again if the underlying model is changed. It is not reflected automatically.

You do not need any replication tool for this, you can use HANA IMPORT functionality.

In the next BW revision (7.4) it should be automatic.

Regards,

Ravi

[former_member184768]

One point to mention:

If you import Model, the data is not imported to standalone HANA. The data resides in the BW objects (DSO / Cube) etc. The data is exposed to Standalone HANA using HANA information models (Views).

You mentioned that you wish to use BW Query results using SAPUI5 elements. I think you may wish to use HANA Information models (Analytic / Calc views) which can be easily integrated with UI5 elements.

Regards,

Ravi

[rama_shankar3]

Chris,

  If you are looking at data migration from BW to HANA to re-build logic in SAP HANA, then you should look at raw data that is fed into BW and then make note of all the data transformations within BW that you have to recreate in SAP HANA as models.

The BEx query in your case is not a real migration if you plan to retire BW for on-going data loads within HANA. If this is a POC only, then you can do this provided you tell your clients the scope.

  In one of my projects, I used BW open HUB to  dump raw data ( un- transformed data) into flat files and then loaded them using loader script. In another project I used BODS ( data services).

Hope this helps.

Rama

[nikhil_joy2]

Hi Christoph,

Since your requirement is to develop SAP HANA XS application from BW data, you have to get your BW data into HANA system. So your first point is the solution. For that you have multiple options.

If you require only few tables from BW to create your HANA XS application and rest of the BW system runs for other purpose, you can fetch those tables into HANA directly from ECC avoiding the BW layer using ETL based BODS or trigger based SLT. If you are looking for real time capability of HANA , then SLT is the solution else BODS would do. You have the option of Director Extractor Connection (DXC) where your existing extractors can be used to get data into HANA system.

which option to choose is purely based on your scenario. If you can provide more details, i think experts here can suggest you the exact solution.

Hope it helps.

Regards,

Nikhil Joy