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Saturday 5 May 2018

SAP HANA Modeling Interview Questions & Answers


1. What Is Sap HANA Modelling?
Answer:
SAP HANA Modeling at a glance:
SAP HANA Information Modeling which also known as SAP HANA Data Modeling is the heart of HANA application development. You can create modeling views on top of database tables and implement business logic to create a meaningful report.

2. Which Non-sap System Can Sap HANA Connect?
Answer:
Oracle Enterprise, IBM Informix.

3. What Are The Views Available In The Quick Launch Of Information Modeler?
Answer:
Navigator, Where-used list, Job log, Properties.

4. For What Life Cycle Management Perspective Is Used?
Answer:
We use Life cycle management perspective to Upgrade/Updates for HANA studio.

5. Opd For Data Replication Api Is Used In Which Replication?
Answer:
Data services 4.0.

6. How Can You Ensure That Data Is Consistent In Source System And HANA System?
Answer:
Since any changes in the source system are tracked in dedicated logging tables, the replication status for each changed data record is transparent. An entry of logging table is deleted after a successful commit statement from HANA database and this procedure ensures the data consistency between a source system and HANA system.

7. Which Section Controls The Data Processing In The HANA Db?
Answer:
Transaction Manager controls the data processing in the HANA DB.

8. What Is The Component Present In Persistence Layer In The HANA Db?
Answer:
The component present in Persistence layer in the HANA DB is Page management & Logger.

9. What Are The Types Of Joins Are Possible In Attribute View?
Answer:
o       Referential join
o       Inner join
o       Outer join

10. What Is The Role Of Persistence Layer?
Answer:
It ensures that the database is restored to the most recent committed state after a restart and that transactions are either completely executed or completely undone. The persistence layer offers interfaces for writing and reading data. It also contains SAP HANA‘s logger that manages the transaction log.  Log entries can be written implicitly by the persistence layer when data is written via the persistence interface or explicitly by using a log interface.

11. What Does HANA Db Performs During Power Outage?
Answer:
Recovers log between last data save point & time of failure.

12. What Is The Operating System Of Imdb?
Answer:
SUSE Linux Enterprise Server.

13. Which Is The Default Perspective Of Imce Studio?
Answer:
Administrator console

14. Name The Editions Of Sap HANA Software?
Answer:
o       Platform edition.
o       Enterprise edition.
o       Enterprise extended edition.

15. What Are The Benefits Of Implementing Sap HANA With Sap Erp?
Answer:
o       Performance optimization for operational reporting.
o       Processing of large volumes of data.
o       Provision of real-time analytics.

16. Do We Need A Special Driver To Access Data Within HANA?
Answer:
HANA provides both a 32-bit and 64-bit ODBC and JDBC drivers. SAP Business Objects 4.0, Data Services 4.0 and many other SAP based tools have built-in support for these drivers to help support all the features HANA has to offer.

17. How Can We Load Data In HANA And How To Access The Data Stored In HANA?
Answer:
Loading data:  There are several options available to get data into HANA. SAP provides a real-time replication server called SLT Replication. With this server you can replicate data from a SAP system or non-SAP RDBMS systems into HANA. The data is copied in its native format and will then need to be de-normalized on HANA using information views (attribute views, analytic views and calculation views). According to the documentation, you can also leverage the Sybase Replication Server for log based replication. In addition, Data Services 4.0 can be used to move data into HANA and can update data at near real time if needed.  Data Services 4.0 can also de-normalize the data given its abundance of data transforms and provide data quality and cleansing transforms that will help clean the data before it is loaded into HANA.
Access the data:  There are several ways to access the data within HANA. The ideal way to access data is through SAP Business Objects 4.0. There are multiple tools within the Business Objects 4.0 platform for accessing HANA data. You can utilize Web Intelligence, Crystal Reports, Explorer, “Analysis Edition for Microsoft Office”, Mobile and Dashboard (Xcelsius). In short, any tool in the platform that supports ODBC or a Universe can be utilized to access data within HANA. These options work for SAP BW (powered by HANA) or for HANA (Standalone). If you have SAP BW powered by HANA, you can utilize any of the traditional query tools. For those that like viewing raw data results, you can utilize HANA Studios to execute SQL statements and view the results.

18. Why We Need To Go For Going In-memory?
Answer:
One reason is the number of CPU cycles per second is increasing and the cost of processors is decreasing. For managing the data in memory, there is five-minute rule which is based on the suggestion that it costs more to wait for the data to be fetched from disk than it costs to keep data in memory so it depends on how often you fetch the data.
For example: there is a table and no matter how large it is and this table is touched by a query at least once every 55 minutes, it is less expensive (in hardware costs) to keep it in memory than to read it from memory and if it is frequently accessed it is less expensive to store it in memory.

19. What Are The Advantages Of Column Based Tables And Row-based Tables?
Answer:
   Advantages of Column based tables:
o  Calculations are typically executed on single or a few columns only.
o  The table is searched based on values of a few columns.
o  The table has a large number of columns.
o  The table has a large number of rows and columnar operations are required (aggregate, scan, etc.).
o  High compression rates can be achieved because the majority of the columns contain only a few distinct values (compared to a number of rows).
Advantages of Row-based tables:
o  The application needs to only process a single record at one time (many selects and/or updates of single records).
o  The application typically needs to access a complete record (or row).
o  The columns contain mainly distinct values so that the compression rate would be low.
o  Neither aggregations nor fast searching is required.
o  The table has a small number of rows (e. g. configuration tables).

20. What Is Derived Attribute Views?
Answer:
In some business cases, it is required to use the same attribute view more than once.
In such cases, one can derive an attribute view using the base view which acts as reference to the base attribute view. The derived attribute view will be opened in the read-only mode. The only editable field will be its description. The derived attribute view will act as a reference to its base attribute view.

SAP HANA BI Development Interview Question & Answers


1. What Are the Different Sap Business objects Reporting and Dashboard Tools?
Answer:
o       Web Intelligence
o       Dashboard Designer (Earlier known as XCelsius)
o       Universe Designer (For Semantic Layer)
o       SAP Crystal Reports
o       SAP Lumira
o       SAP Design Studio
o       Business Objects Explorer
o       Analysis for OLAP
2. What Is the Use of Sap Bi Launch pad?
Answer:
BI Launch pad has the following important options:
Home: Displays the recent messages, alerts, documents, and applications that can be run.
Documents: Displays the available documents and folders, making it easier to view, organize, and manage the documents.
Any Open Document: Displays each open document.
3. What Is The Use Of Relational Connection And An Olap Connection?
Answer:
Relational Connection: A Relational connection is used to connect to the Database layer in HANA. You can connect to database objects - tables, views, and design Data Foundation layer in the Information Design tool. You can also import tables and joins from the data source.
OLAP Connection: OLAP is a multidimensional connection that directly points to the business layer in a data model. It allows to connect to multidimensional schema directly and later, they can be used with SAP Business Objects reporting tools.
4. What Is the Difference Between .cns And .cnx Connection?
Answer:
.cns − Secured Repository connection
.cnx-local unsecured − If you use this connection, it will not allow you to publish anything to the repository.
5. What Are The Different Types Of HANA Information Views?
Answer:
SAP HANA provides the following three types of Information Views :
o   Attribute View
o   Analytic View
o   Calculation View
6. What Are The Different Input Parameters Types In Sap HANA?
Answer:
Direct: Using this parameter type, you can pass any value for the parameter.
Column: This parameter type allows you to select any value from the list of distinct values available in a column in HANA view.
Derived From Table: It is also possible to create dynamic values in a table. This allows you to select any of the available values from the list.
Static List:It is also possible to create a static list of values and provide user input during execution.
7. What Are The Different Features Of Analytic Views In Sap HANA?
Answer:
Following are the properties of SAP HANA Analytic View:
o    Analytic Views are used to perform complex calculations and Aggregate functions such as Sum, Count, Min, Max, etc.
o    Analytic Views are designed to run Start schema queries.
o    Each Analytic View has one Fact table surrounded by multiple dimension tables. Fact table contains a primary key for each Dim table and measures.
o    Analytic Views are similar to Info Objects and Info sets of SAP BW.
o    SAP Business Objects reporting tools can connect to Analytic view using an OLAP connection for reporting and dashboard.
8. Which Bo Tools Can Connect To HANA System Using A Universe?
Answer:
All Business Objects tool - Webi, Dashboard Designer, Lumira, Crystal Reports, Design Studio that provide Universe connectivity as data source can be used to connect to HANA system.

9. Which Version Of Sap Business objects Provide Direct Connectivity Of Web Intelligence To HANA System?
Answer:
Business Objects 4.2

10. In Business objects 4.2, What Are the Different Ways to Connect Webi to HANA Views?
Answer:
o    Using Universe on top of HANA Modeling views
o    Direct Webi connection with HANA Modeling views
o    SAP HANA Online connectivity
o    Using Free-Hand SQL

11. How Do You Connect Dashboard Designer To HANA Database For Dashboard Creation?
Answer:
You can connect to SAP HANA using Universe connectivity from the Dashboard. SAP Dashboard supports SAP HANA backed with Universe created on top of HANA views and tables. You can consume Universe Designer .unx files using the Query Browser option to develop the dashboard.

12. What Are The Different Data Sources Option Available Under Crystal Reports?
Answer:
Crystal Reports can connect to multiple data sources that include:
o    Universe
o    SAP BEx Query
o    HANA view
o    Excel Spreadsheets

13. While Using Sap HANA Bi Development, Which HANA View Can Be Used To Implement Star Queries?
Answer:
Analytic View

14. What Are The Different Ways To Create Calculation Views To Be Used In Bi Reporting?
Answer:
o    Using GUI option
o    Using SQL Script

15. What Are The Different Geographic Chart Types Available Under Sap Lumira?
Answer:
o    Geo Bubble Chart
o    Geo Choropleth Chart
o    Geo Pie Chart
o    Geo Map

16. How Do You Connect Sap HANA Views To Ms Excel For Creating Interactive Pivots And Charts?
Answer:
Using MDX Provider option

17. Is It Possible To Publish Datasets From Lumira To HANA Platform?
Answer:
Yes, you can publish SAP Lumira dataset and stories to HANA platform for sharing with other users.


18. How Do You Connect Sap Design Studio To HANA Views For Bi Reporting And Dashboard Development?
Answer:
Using Universe option - add as data source
Using direct backend connection to HANA

19. What Are The Other Bi Tools That Can Be Connected To HANA For Reporting?
Answer:
Tableau, MS Excel, Cognos and SSRS

20. How Do You Create An Olap Connection To Provide Direct Connectivity To HANA Views?
Answer:
OLAP connection can be created in CMC or IDT

21. Is It Possible To Expose Only A Particular Cube/HANA View To Bo Reporting Tool And Not The Entire Repository?
Answer:
Yes, while creating an OLAP connection you have an option to select if you want the connection to point to a particular view or to the entire repository.

22. A Crystal Report Developer Uses Sap Crystal Report For Enterprise. To Connect HANA Which Connection Type Is Preferred?
Answer:
If Universe is available, you can use Universe Connectivity.
23. What Are The Advantages Of Using Sap HANA Db Over Other Traditional Database For Bi Reporting?
Answer:
SAP HANA in-memory concept: SAP HANA in-memory database services provide the capability of processing high-speed transactions and analytics. It helps in managing large database volumes using multitenant database containers and dynamic tiering across multi-tier storage.
Analytics Processing: Using HANA in-memory processing capability - text, predictive, spatial, graph, streaming, and time series - you can get answers to any business  and make smart decisions in real time.
App Development : Using SAP HANA, you can develop next-generation applications that combine analytics and transactions, and deploy them on any device.
Data Access:SAP HANA helps organizations in getting accurate and complete view of business by accessing data from different sources. HANA provides real-time data replication and data quality to improve decision making from internal and external data sources.
Administration:SAP HANA ensures application availability and tools to monitor the processes along with data and application security.
Security :SAP HANA provides a dashboard to monitor all KPIs related to security. It helps in keeping communications, data storage, and application services secure with robust identity and access management controls.