Online Tutorials & Training Materials | STechies.com
Register Login

SAP HANA Data Aging Interview Questions and Answer

|| 0

SAP HANA Data Aging Interview Questions and Answer
Stechies

FAQ HANA Data Aging in SAP S/4HANA

Are there any fundamentals for using Data Aging in SAP S/4HANA?

Data Aging is mainly available in SAP Business Suite on HANA and S/4HANA Applications (starting with SAP NetWeaver 7.4 SP05). For applying Data Aging in SAP HANA, there are a few prerequisites on ABAP side:

  • The SAP application has to provide Data Aging Objects
  • The Profile Parameter abap/data_aging needs to be set to ‘on’
  • The Data Aging business function (DAAG_DATA_AGING) has to be switched on
  • Relevant authorizations for Data Aging activities are to be provided

SAP HANA is ready to manage Data Aging without any further configuration. More pre-conditions are listed in the SAP Help Portal Data Aging - Prerequisites for Data Aging.

Do I need an additional License for Data Aging?

Data aging is not a licensed product. The Data Aging framework is accessible with NetWeaver version 740 SP05 onwards.

Are there any fundamentals specifically for a table for participating in Data Aging in SAP S/4HANA?

A table can partake in Data Aging if it is part of one or many Data Aging Objects (Transaction DAGOBJ) and it is part in one Partition Object (Transaction DAGPTC).

Besides this it has to have the additional column _DATAAGING, which is known as the basis for the time selection partitioning. Once the table is assigned for Data Aging, this column is automatically added.

What are the authorizations required to perform Data Aging?

The SAP Help Portal lists all the relevant information regarding authorizations and roles.

During sizing, what all should you consider?

The latent on how much the SAP HANA memory footprint can be condensed by the usage of Data Aging is assessed by the sizing report which is available in SAP doc. 1872170 - Business Suite on HANA and S/4HANA sizing report.

How can you include Data Aging statistics into the Early Watch Alert (EWA)?

A chapter on data aging has been designed. In this One can see the activation status and the ratio between current (hot) and historical (cold) data. This ratio provides an indication on the extent to which data aging has been implemented. The prerequisite has a software component ST-PI with Support Package 4 or higher.

On which Technology is Data Aging based in SAP HANA?

Data Aging in SAP HANA utilizes:

Time selection partitioning: The column, _DATAAGING, is used for splitting tables into one hot and some cold partitions.

No uniqueness checks: The uniqueness checks on the cold data is switched off (the application will enforce uniqueness) for improving performance

Page-loadable columns/Paged attributes: The memory management of an attribute is largely based on pages so that partitions can partially be loaded into memory (used to store data in the cold partitions)

What Data Aging Objects are presently available?

Only the basis Documents which are available for Data Aging like e.g. Application Log, IDocs, and Workflow. In SAP S/4HANA Basis and Application Documents are available in SAP Business Suite on HANA. There is a complete list of all available objects which can be found in the SAP Help Portal Data Aging - Available Data Aging Objects and under ABAP transaction DAGOBJ.

Can a customer define own Data Aging Objects?

The SAP application allows you to suggest and brings the Data Aging Objects and Partition Objects. The customer does have the option to find a list of Data Aging objects along with enhancements which are provided by the individual SAP application mentioned in the transaction Data Aging Objects (DAGOBJ). Customers are then able to deploy their own Aging-Objects however this is only for custom tables. The Data Aging Framework offers APIs to implement-Aging Objects.

What are the common tools meant for administering Data Aging in SAP S4/HANA?

There are many ABAP transactions available for Data Aging. You can get a detailed in the SAP Help Portal Data Aging - Data Aging Transactions.

Besides this, Data Aging can also be administered via the following Fiori applications:

  • Manage Data Aging Groups
  • Monitor Data Aging Objects
  • Database Table Growth

Can data access of cold data in ABAP be allowed?

Yes, data access is permitted from the historical area by utilizing the classes CL_ABAP_SESSION_TEMPERATURE and CL_ABAP_STACK_TEMPERATURE.

Can the data in cold partition be modified?

Yes, historical data can be altered. However, in business complete data is aged typically, because of which modifications are very rare.

If cold data is accessed, can the partition(s) be loaded to the in-memory part of SAP HANA?

Cold partitions generally use Paged Attributes. Paged Attributes are loaded page-wise and the ordinary columns are loaded entirely into memory upon first access.
Typically, only the pages which hold the requested rows are being loaded. Columns which have indexes, as the primary keys, are not paged in the cold partitions.

Will the Data Aging Framework resolve for moving the data from the hot partition to the cold partition(s) automatically?

By using its knowledge about the object’s life cycle, the application logic determines when current data turns historical. From a business standpoint, the application logic authenticates the conditions at the object level based on the execution of existence checks, status, and verification of cross-object dependencies. The framework implements the move.

When should a new partition for the cold data be created?

A new partition range should be created when the data to be aged is not enclosed by an existing partition range in historical area. A new partition range can also be formed, when the maximum capacity threshold for an existing partition has been attained.

Why is the exclusivity check for cold data switched off in SAP HANA per default?

SAP HANA has set exclusive checks for ABAP applications which use the Data Aging Framework, the default has been set to “no uniqueness check”.

There are unique restraints for primary keys or unique indexes which are generally checked across all partitions if the partitioning is done over the artificial temperature, which is not part of the primary key column of a table. This related to the cold partitions which are required to be accessed when the data is either inserted or updated. A database application can switch off the uniqueness check for cold data by setting an option in the partition specification, for preventing a negative impact on performance. It is up to the application for either preventing duplicates (e.g. via GUIDs or number ranges) or to cope with duplicates. In case the unique checks for cold data have been switched off, then SAP HANA only guarantees unique values in the hot partition. In such a scenario, conflicts between records in hot and cold, between two cold partitions, and between records in the same cold partition, cannot be erased and prevented on database level. it is up to the application to either prevent duplicates (e.g. via GUIDs or number ranges) or to cope with duplicates.