Top 50 SAP HANA Interview Questions And Answers Pdf
1. Can an SAP HANA One backup be restored into an on-premise instance of SAP HANA?
Answer: Yes, as long as SAP HANA One and SAP HANA on-premise licenses are valid, and the SAP HANA versions match, backup data can be transferred. Please follow your license agreements carefully before you transfer any data between SAP HANA One and SAP HANA on-premise.
2. What are the business benefits of SAP Collections Insight?
Answer: The SAP Collections Insight web and mobile apps give you access to rich, dynamic account profiles and enable real-time analysis of payments and payment trends across years of data. With Collections Insight, sales and service teams can support collections activities with access to dashboards and collaborative tools to help manage, track, quickly resolve collections issues, and get paid on outstanding accounts faster.
3. How is the solution delivered?
Answer: SAP Collections Insight is delivered as mobile and web applications, powered by SAP HANA, letting our customers access the power of SAP HANA in an easy-to-consume model. This leads to radical reductions in capital expenditure and quicker innovation cycles.
4. Describe SAP HANA Database Architecture in brief?
Answer: The SAP HANA database is developed in C++ and runs on SUSE Linux Enterprise Server. SAP HANA database consists of multiple servers and the most important component is the Index Server. SAP HANA database consists of Index Server, Name Server, Statistics Server, Preprocessor Server, and XS Engine.
5. So is SAP making/selling the software or the hardware?
Answer: SAP has partnered with leading hardware vendors (HP, Fujitsu, IBM, Dell etc) to sell SAP-certified hardware for HANA: SAP is selling licenses and related services for the SAP HANA product which includes the SAP HANA database, SAP HANA Studio and other software to load data in the database.
6. Mention what is the role of the transaction manager and session?
Answer: The transaction manager coordinates 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.
7. Explain how SQL statement is processed?
Answer: In the HANA database, each SQL statement is implemented in the reference of the transaction. A new session is allotted to a new transaction.
8. There is an analytic view which has calculated column defined. Which engine will be used when calling this view?
Answer: By default analytic view is executed in OLAP engine. But this changes when the analytic view has a calculated column.
If an analytic view has a calculated column then internally it is treated as calculation view and executed in calculation engine.
9. What is a text table in SAP? What is the purpose of creating a text table?
Answer:
Table A is a text table of table B if the key of A comprises the key of B and an additional language key field (field of data type LANG). Table A may, therefore, contain explanatory text in several languages for each key entry of B.
Purpose: Text Join is used to fetch the description based on the user’s session language. Once we implement the text join in SAP HANA, it automatically finds out the user’s language and gives a description in that language.
To know more about Text table, read SAP HANA Text Join
10. Can we call an analytic view or calculation view inside another calculation view?
Answer:
Yes. We can call all the views (attribute, analytic and calculation view) inside a calculation view.
Note: Calculation views are composite views and can be used to combine other views. It can consume other Analytical, Attribute, other Calculation Views & tables. It can perform complex calculations not possible with other views.
11. Explain what is schema mapping?
Answer: Schema mapping is done when the physical schema in the target system is not the same as the physical schema in the source system.
As mentioned earlier, suppose we are moving components from Development System (DEV) to Production System (PROD).
The tables in DEV reside in DEV_SCHEMA and the same tables reside in PROD system in PROD_SCHEMA schema. If an attribute view is transported from DEV to PROD, it will not work because the schema name is referenced in the definition of attribute view. In order for the promoted objects to work in PROD, schema mapping needs to be set up in the target system.
In this scenario, the schema mapping to be created is
Authoring Schema
Physical Schema
DEV_SCHEMA
PROD_SCHEMA
12. What is the difference between attribute and measure?
Answer:
Columns of modeling view can be classified as Attribute or Measure.
Attribute: Non-measurable, Descriptive data, such as customer ID, city, and country
Measure: Quantifiable data, such as revenue, quantity sold and counters.
Let us take an example of an organization’s sales tables. The table contains columns like SALES, PROFIT, PRODUCT, CUSTOMER NAME, YEAR, COUNTRY, etc.
The important business use cases will be like. (SAP HANA Online Training)
13. What is the profit for product ‘XYZ’ for country USA?
Answer: The SALES and PROFIT columns are numeric values. These columns are measurable and can be aggregated. While the columns PRODUCT, CUSTOMER NAME, YEAR and COUNTRY are descriptive and non-measurable.
Here PRODUCT, CUSTOMER NAME, YEAR and COUNTRY are attributes, while SALES and PROFIT are measures.
14. What is a Private Attribute in HANA?
Answer: Private attributes are the attributes used inside modeling views and cannot be used outside the view. These are used in a modeling view to customize the behavior of an attribute for only that view.
15. What are the different types of measures in the modeling view?
Answer:
There are 3 types of measures in HANA:
Simple Measure:
Simple Measure is a measurable analytical element that is derived from the data foundation.
Calculated Measure:
Calculated Measures are created using some calculation on top of existing measures or attributes.
Private Measures:
Private Measures are measures used inside modeling views and cannot be used outside the view.
16. What is the difference between Variable and Input parameter in HANA?Answer: Variables are bound to columns and are used for filtering using WHERE clauses. As such, they can only contain the values available in the Columns they relate to. Variables do not impact the execution
HANA Input parameters used to manipulate the execution based on user input. Sometimes you might not want a variable to just restrict the data of a view. But you also want to take input from the user and process it, returning dynamic data based on the user selection. Input Parameters makes this possible.
To know more about Variables and Input Parameter, read Variables and Input Parameters in HANA.
17. Mention what is the role of the persistence layer in SAP HANA?
Answer: SAP HANA has an in-memory computing engine and accesses the data straightaway without any backup. To avoid the risk of losing data in case of hardware failure or power cutoff, the persistence layer comes as a savior and stores all the data in the hard drive which is not volatile.
18. Mention what is modeling studio?
Answer:
Modeling studio in HANA performs multiple tasks like
Declares which tables are stored in HANA, the 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
19. What is the difference between Raw Data, Distinct values, and Analysis while doing the Data Preview?
Answer:
Raw Data: It displays all attributes along with data in tabular format.
Distinct Values: It displays all attributes along with data in graphical format.
Analysis: It displays all attributes and measures in graphical format.
20. How does SAP HANA support Massively Parallel Processing?
Answer: With the availability of Multi-Core CPUs, higher CPU execution speeds can be achieved.
Also, HANA Column-based storage makes it easy to execute operations in parallel using multiple processor cores.
In a column store data is already vertically partitioned. This means that operations on different columns can easily be processed in parallel. If multiple columns need to be searched or aggregated, each of these operations can be assigned to a different processor core.
In addition operations on one column can be parallelized by partitioning the column into multiple sections that can be processed by different processor cores. With the SAP HANA database, queries can be executed rapidly and in parallel.
21. What are the different types of Input parameters supported?
Answer:
The following types of Input parameters are supported.
Currency:
Use this during currency conversion where the end-user should specify a source or target currency.
Date:
Use this to retrieve date from the end-user using a calendar type input box.
Static List:
Use this when the end-user should have a set list of values to choose from.
Attribute Value:
When an Input Variable has this type, it serves the same purpose as a normal Variable.
None:
If none of the above applies you do not have to specify an Input Variable type. The Type can be left blank.
22. List the different compression techniques in HANA?Answer:
- Run-length encoding
- Cluster encoding
- Dictionary encoding
23. What happens when you activate an object in HANA?
Answer: When we activate an object, it becomes available for reporting and analysis.
After successful activation of a view, a run-time object is created in _SYS_BIC schema.
For example, suppose there is a calculation view CV_VIEW1 in package “MyPackage”. After activating this view, a run time object (column view) will be created in _SYS_BIC schema with the name “MyPackage/CV_VIEW1”. This column view is used when we do the data preview of the calculation view. (Interview Questions and Answers)
24. What is the difference between Activate and Redeploy?
Answer:
Activate – Deploys the inactive objects.
Redeploy – Deploys the active objects in one of the following scenarios:
If your runtime object gets corrupted or deleted, and you want to create it again.
In case of runtime problems during object activation, and the object status is still active.
25. How do we control row-level access in HANA?
Answer: Analytic privilege can be used to maintain row-level access. It is used to grant different users access to different portions of data in the same view depending on their business role.
26. Suppose we want to give minimum authorization to end users so that they can only see the output of modeling views. The users should not be able to perform any other activities. What are the privileges that should be assigned to the user?
Answer:
We need to assign the following privileges:
Read access to the package containing modeling view
Execute & Select access on _SYS_BI
Execute & Select access on _SYS_BIC
Execute on REPOSITORY_REST
27. What are the types of schema in HANA?
Answer:
In HANA, there are 3 types of schemas.
User-Defined Schema: These are created by the user (DBA or System Administrator)
SLT Derived Schema: When SLT is configured, it creates the schema in the HANA system. All the tables replicated into HANA system are contained in this schema
System Defined Schema: These schemas are delivered with the SAP HANA database and contain HANA system information. There are system schemas like _SYS_BIC, _SYS_BI, _SYS_REPO, _SYS_STATISTICS, etc.
28. If tables of a schema are used to build modeling views then it’s necessary to grant SELECT privilege to user _SYS_REPO. Why?
Answer:
If tables of a schema (say SCHEMA_ABC) are used to build modeling views, then following SQL statement must be executed before activating any such modeling views.
GRANT SELECT ON SCHEMA SCHEMA_ABC TO _SYS_REPO WITH GRANT OPTION
Think of _SYS_REPO as “the activation guy”. It takes your models and creates the necessary runtime objects from them. Therefore user _SYS_REPO needs the allowance to select YOUR tables/views. (If _SYS_REPO user cannot select on the tables specified in the from-clause of the view-definition, it cannot define that view)
If other users need to select this view (obviously this is always the case, otherwise the views would not make sense), then _SYS_REPO needs to have the additional allowance to grant the select further (WITH GRANT OPTION).
Therefore after having activated all your models that access data in your schemas, _SYS_REPO wants to give you (and probably other users) read access to the activated models.
29. What is SAP Collections Insight?
Answer: SAP Collections Insight powered by SAP HANA allows you access to real-time mobile collaboration and collections account information anywhere and anytime, allowing you to resolve collections issues, better manage your collections efforts, tighten business relationships and get paid faster.
30. What are the benefits of having a collections management solution powered by SAP HANA?
Answer: SAP HANA is able to bring massive amounts of detailed data from source systems, directly into memory, where translation, mapping, and synchronization can be done in real-time, without the need for pre-aggregations and data duplication. This allows users to plan rapidly and iteratively using their complete, detail-level data-spending less time collecting and assembling data and more time making the critical decisions that drive their business.
31. What are the different user parameters that can be defined in the Semantic layer?
Answer:
- Measure and Attribute
- Hierarchies
- Parameters/Variables
- New Calculated Column
32. What is the Hierarchy? What are the types of hierarchy supported in HANA?
Answer:
Hierarchies are used to structure and define the relationships among attributes in a modeling view.
Organizations define hierarchies for information classification, allowing roll-up and drill-down analysis. For example, a sales organization might allocate a salesperson to a country and a country to a region. Sales data can then be aggregated and analyzed by region, country, or salesperson.
There are two types of hierarchies:
Level Hierarchies are hierarchies that are rigid in nature, where the root and the child nodes can be accessed only in the defined order. For example, organizational structures, and so on.
Parent/Child Hierarchies are value hierarchies, that is, hierarchies derived from the value of a node. For example, a Bill of Materials (BOM) contains Assembly and Part hierarchies, and an Employee Master record contains Employee and Manager data. The hierarchy can be explored based on a selected parent; there are also cases where the child can be a parent.
33. Explain the column and Row store in HANA?
Answer: HANA supports both types of data store in the database. Row store is used when you need to use Select statement and no aggregations are performed.
Column store is used to perform aggregations and HANA Modeling is supported only on Column based tables.
34. What’s the purpose of Generating Time Data?
Answer: Generate Time Data option under Quick Launch helps the user to generate the Time data so that it can be used for the creation of Time-based Attribute Views.
When you click Generate Time Data, you will be provided with two options
Gregorian: Mainly the data will be generated based on From and To years along with the granularity (Hour, Minute, Second, Day, Month) mentioned.
Fiscal: In this case, the time data will be generated based on the variant defined (some companies may use their own time period).
Standard tables T005T, T005U, T009 and T009B in SAP HANA are required if you go for FISCAL type.
35. What is the difference between Copy and derived from option while creating a new SAP HANA Attribute information view?
Answer: Copy option allows you to copy an existing Information view and to make changes to it.
The derived option allows to create a copy of an existing view and you can’t make any changes to it.
36. Which companies are providing SAP HANA hardware appliances?
Answer:
There is a total of 11 vendors for SAP HANA hardware appliances. Most common are −
Dell
IBM
HP
Cisco
Lenovo
37. What is the use of SAP HANA studio?
Answer: HANA studio is an eclipsed based tool and provides support for development and administration in the HANA system. You can perform HANA Modeling on the top of tables in the database, Data provisioning, HANA Administration and various other activities using HANA studio.
38. What do you understand by SAP HANA In-Memory Computing Engine IMCE?
Answer: In-Memory concept of SAP HANA means that all the data is stored in RAM memory. A conventional database transfer data from memory in 5 milliseconds, however, SAP HANA In-memory takes 5 nanoseconds to read data.
SAP HANA uses multicore CPU architecture and stores data in row and column-based storage in the HANA database.
39. What is the functional difference between Row and Column based storage? Where do we use Row-based storage and column-based storage?
Answer:
Consider the below table- FCTSales
Country Product Units Sold
England iPhone 6 107
India Samsung Note 6 250
US Lenovo A110 110
Row Based Storage −
England
Iphone6
107
India
Samsung Note 6
250
US
Lenovo A110
110
Column Based Storage −
England
India
US
Iphone6
Samsung Note6
Lenovo A110
107
250
110
40. List advantages of using SAP HANA database?
Answer: With the HANA technology, you can create gen-next applications giving effective and efficient results in the digital economy.
By using singe data-in memory, SAP HANA supports smooth transaction process and fault-tolerant analytics
Easy and simple operations using an open-source, unified platform in the cloud
High-level Data Integration to access massive amounts of data
Advanced tools for in-depth analysis of the present, past and the future.
41. What are the different components in SAP HANA Architecture? What is the use of the Index server?
Answer:
Index Server
Name Server
Statistical Server
Preprocessor Server
XS Engine
SAP Host Agent
LM structure
SAP Solution Manager Diagnostic Agent
Index server contains engine to process data in HANA database. These data engines are responsible to handle all SQL/MDX statement in HANA system. Index server also contains Session and Transaction Manager which is responsible to manage all running and completed transactions.
42. What is the use of the Persistence layer in SAP HANA system?
Answer: Persistence layer provides an inbuilt mechanism for disaster recovery in the HANA system. It ensures that the database is restored to the most recent state in case of a system failure.
Persistence layer also manages data, transaction and configuration logs and backup of these files. Backups of data and log files are performed at save points and is normally scheduled every 5-10 minutes.
43. List the merits and demerits of using row-based tables?
Answer: No data approach can be faster than row-based if you want to analyze, process and retrieve one record at one time.
Row-based tables are useful when there is a specific demand for accessing the complete record.
It is preferred when the table consists of less number of rows.
This data storage and processing approach are easier and effective without any aggregations and fast searching.
Demerits:
The data retrieval and processing operations involve the complete row, even though all the information is not useful.
Go through this in-depth SAP HANA training and master the powerful columnar database now!
44. What are the advantages and disadvantages of row-based tables?
Answer:
Row-based tables have advantages in the following circumstances:
The application needs to only process a single record at one time (many selects and/or updates of single records). The application typically needs to access a complete record (or row). Neither aggregations nor fast searching is required. The table has a small number of rows (e. g. configuration tables, system tables). Row-based tables have dis-advantages in the following circumstances: In the case of analytic applications where the aggregation is used and fast search and processing is required. In row-based tables, all data in a row has to be read even though the requirement may be to access data from a few columns.
45. What is the Delivery Unit?
Answer: A delivery unit could be regarded as a collection of several packages, used for
What are the different engines available in HANA?
transporting content from one HANA system to another.
Delivery unit (DU) is a container used by the Life Cycle Manager (LCM) to transport repository objects.
46. What are the different types of permanent license keys in the HANA system?
Answer:
There are two types of permanent License keys for HANA system −
Unenforced − If unenforced license key is installed and consumption of HANA system exceeds the license amount of memory, the operation of SAP HANA is not affected in this case.
Enforced − If Enforced license key is installed and the consumption of the HANA system exceeds the license amount of memory, the HANA system gets locked. If this situation occurs, the HANA system has to be restarted or a new license key should be requested and installed.
While activating SAP HANA Modeling view, you get an error message −
Repository: Encountered an error in repository runtime extension; Deploy Attribute View: SQL: transaction rolled back by an internal error: insufficient privilege: Not authorized
Grant SELECT privileges on schemas of the used data foundation tables to user “_SYS_REPO”
47. In SAP HANA Studio, what is the use of different folders when you add a HANA system to Studio?
Answer:
Backup −
It is used to perform for backup and recovery in the SAP HANA system. You can check backup configuration details, run a manual backup, check last successful back performed, etc. for data and log backup.
Catalog −
This contains RDBMS objects like schemas, tables, views, procedures, etc. You can open SQL editor and design database objects
Content −
This is used to maintain a design-time repository
You can create new packages and design Information views in HANA system. Various views can be created under the content tab to meet business requirement and to perform analytical reports on the top of the Modeling views.
Provisioning −
This is used for Smart data access to connect to other databases like HADOOP, TERADATA, and SYBASE
Security −
This is used to define users and to assign roles. You can define various privileges on different users using the Security tab. You can assign Database and Package privileges to different users to control the data access.
48. If you want to see all active alerts, description, and priority, where this can be checked?
Answer:
Go to Administration → alerts
In the Administration tab, you can check system overview, landscape, volumes, configuration, system information, etc.
49. What do you understand by trusted RFC connection? Which transaction is used to create and configure trusted RFC?
Answer: On your source SAP system, A1 you want to set up a trusted RFC to target system B1. When it is done it would mean that when you are logged onto A1 and your user has enough Authorization in B1, you can use the RFC connection and logon to B1 without having to re-enter user and password.
SM59 to create a trusted RFC
Ltr to configure the connection
50. What is Auto Documentation feature in HANA?
Answer:
When the user creates Views in HANA Studio under “Contents”, he can automatically generate the documentation about the views. This generated document will have the details about all the view belongs to a package which he selected for Auto Documentation.
The user can invoke the Auto Documentation from three places.
Right-click Context menu of the Package or the Views
On the top right corner of the opened view
Quick Launch->Content->Auto Documentation