Thursday, November 28, 2013

SAP ABAP Interview Questions and Answers - 2

DATA DICTIONARY
1. What are the layers of data description in R/3?
• The external layer.
• The ABAP/4 layer.
• The database layer.
2. Define external layer?
The external layer is the plane at which the user sees and interacts with the data, that is, the data
format in the user interface. This data format is independent of the database system used.
3. Define ABAP/4 layer?
The ABAP/4 layer describes the data formats used by the ABAP/4 processor.
4. Define Database layer?
The database layer describes the data formats used in the database.
5. What is a Data Class?
The Data class determines in which table space the table is stored when it is created in the
database.
6. What is a Size Category?
The Size category describes the probable space requirement of the table in the database.
7. How many types of size categories and data classes are there?
There are five size categories (0-4) and 11 data classes only three of which are appropriate for
application tables:
• APPL0- Master data (data frequently accessed but rarely updated).
• APPL1- Transaction data (data that is changed frequently).
• APPL2- Organizational data (customizing data that is entered when system is configured and
then rarely changed).
The other two types are:
• USR
• USR1 – Intended for customer's own developments.
8. What are control tables?
The values specified for the size category and data class are mapped to database-specific values
via control tables.
9. What is the function of the transport system and workbench organizer?
The function of the transport system and the Workbench Organizer is to manage any changes
made to objects of the ABAP/4 Development Workbench and to transport these changes between
different SAP systems.
10. What is a table pool?
A table pool (or pool) is used to combine several logical tables in the ABAP/4 Dictionary. The
definition of a pool consists of at least two key fields and a long argument field (VARDATA).
11. What are pooled tables?
These are logical tables, which must be assigned to a table pool when they are defined. Pooled
tables can be used to store control data (such as screen sequences or program parameters).
12. What is a table cluster?
A table cluster combines several logical tables in the ABAP/4 Dictionary. Several logical rows
from different cluster tables are brought together in a single physical record. The records from
the cluster tables assigned to a cluster are thus stored in a single common table in the database.
13. How can we access the correction and transport system?
Each time you create a new object or change an existing object in the ABAP/4 Dictionary, you
branch automatically to the Workbench Organizer or correction and transport system.
14. Which objects are independent transport objects?
Domains, Data elements, Tables, Technical settings for tables, Secondary indexes for transparent
tables, Structures, Views, Matchcode objects, Matchcode Ids, Lock objects.
15. How is conversion of data types done between ABAP/4 & DB layer?
Conversion between ABAP/4 data types and the database layer is done within the database
interface.
16. How is conversion of data types done between ABAP/4 & external level?
Conversion between the external layer and the ABAP/4 layer is done in the SAP dialog manager
DYNP.
17. What are the Data types of the external layer?
ACCP, Char, CLNT, CUKY, CURR, DATS, DESC, FLTP, INT1, INT2, INT4, LANG, LCHR,
LRAW, NUMC, PREC, QUAN, RAW, TIMS, UNIT,VARC.
18. What are the Data types of the ABAP/4 layer?
Possible ABAP/4 data types:
C: Character.
D: Date, format YYYYMMDD.
F: Floating-point number in DOUBLE PRECISION (8 bytes).
I: Integer.
N: Numerical character string of arbitrary length.
P: Amount of counter field (packed; implementation depends on h/w platform).
S: Time Stamp YYYYMMDDHHMMSS.
V: Character string of variable length, length is given in the first two bytes.
X: Hexadecimal (binary) storage.
19. How can we set the table spaces and extent sizes?
You can specify the extent sizes and the table space (physical storage area in the database) in
which a transparent table is to be stored by setting the size category and data class.
20. What is the function of the correction system?
The correction system manages changes to internal system components. Such as objects of the
ABAP/4 Dictionary.
21. What are local objects?
Local objects (Dev class$TMP) are independent of correction and transport system.
22. What is a Development class?
Related objects from the ABAP/4 repository are assigned to the same development class. This
enables you to correct and transport related objects as a unit.
23. What is a data dictionary?
Data Dictionary is a central source of data in a data management system. Its main function is to
support the creation and management of data definitions. It has details about
• What data is contained?
• What are the attributes of the data?
• What is the relationship existing between the various data elements?
24. What functions does a data dictionary perform?
In a data management system, the principal functions performed by the data dictionary are
• Management of data definitions.
• Provision of information for evaluation.
• Support for s/w development.
• Support form documentation.
• Ensuring that the data definitions are flexible and up-to-date.
25. What are the features of ABAP/4 Dictionary?
The most important features are:
• Integrated to aABAP/4 Development Workbench.
• Active in the runtime environment.
26. What are the uses of the information in the Data dictionary?
The following information is directly taken from the Data dictionary:
• Information on fields displayed with F1 help.
• Possible entries for fields displayed with F4 help.
• Matchcode and help views search utilities.
27. What are the basic objects of the data dictionary?
• Tables
• Domains
• Data elements
• Structures
• Foreign Keys
28. What are the aggregate objects in the data dictionary?
• Views
• Match codes
• Lock objects.
29. In the ABAP/4 Dictionary Tables can be defined independent of the underlying
database (T/F).
True.
30. ABAP/4 Dictionary contains the Logical definition of the table.

No comments:

Post a Comment