SAP S4HANA Interview Questions and answers 2018

1) Mention what is SAP HANA?

SAP HANA stands for High-Performance Analytical Appliance- in-memory computing engine. HANA is linked to ERP systems; Frontend modeling studio can be used for replication server management and load control.

2) Mention the two types of Relational Data stored in HANA?

The two types of relational data stored in HANA includes

Row Store
Column Store

3) Mention what is the role of the persistence layer in SAP HANA?

SAP HANA has an in-memory computing engine and access the data straightaway without any backup. To avoid the risk of losing data in case of hardware failure or power cutoff, persistence layer comes as a savior and stores all the data in the hard drive which is not volatile.

4) Mention what is modeling studio?

Modeling studio in HANA performs multiple task like

Declares which tables are stored in HANA, first part is to get the meta-data and then schedule data replication jobs
Manage Data Services to enter the data from SAP Business Warehouse and other systems
Manage ERP instances connection, the current release does not support connecting to several ERP instances
Use data services for the modeling
Do modeling in HANA itself
essential licenses for SAP BO data services

5) Mention what are the different compression techniques?

There are three different compression techniques

Run-length encoding
Cluster encoding
Dictionary encoding

6) Mention what is latency?

Latency is referred to the length of time to replicate data from the source system to the target system.

7) Explain what is transformation rules?

Transformation rule is the rule specified in the advanced replication setting transaction for the source table such that data is transformed during the replication process.

8) Mention what is the advantage of SLT replication?

SAP SLT works on trigger based approach; such approach has no measurable performance impact in the source system
It offers filtering capability and transformation
It enables real-time data replication, replicating only related data into HANA from non-SAP and SAP source systems
It is fully integrated with HANA studios
Replication from several source systems to one HANA system is allowed, also from one source system to multiple HANA systems is allowed.

9) Explain how you can avoid un-necessary information from being stored?

To avoid un-necessary information from being stored, you have to pause the replication by stopping the schema-related jobs

10) Mention what is the role of master controller job in SAP HANA?

The job is arranged on demand and is responsible for

Creating database triggers and logging table into the source system
Creating Synonyms
Writing new entries in admin tables in SLT server when a table is replicated/loaded

11) Explain what happens if the replication is suspended for a longer period of time or system outage of SLT or HANA system?

If the replication is suspended for a longer period of time, the size of the logging tables increases.

 

12) Mention what is the role of the transaction manager and session?

The transaction manager co-ordinates database transactions and keeps a record of running and closed transactions. When transaction is rolled back or committed, the transaction manager notifies the involved storage engines about the event so they can run necessary actions.

13) Explain how you can avoid un-necessary logging information from being stored?

You can avoid un-necessary logging information from being stored by pausing the replication by stopping the schema-related jobs.

14) Explain how SQL statement is processed?

In the HANA database, each SQL statement is implemented in the reference of the transaction. New session is allotted to a new transaction.

15) Name various components of SAP HANA?

SAP HANA DB
SAP HANA Studio
SAP HANA Appliance
SAP HANA Application Cloud