This document provides an overview of data dictionaries and data modeling in ABAP. It discusses key concepts like data types, domains, data elements, tables, structures, and aggregated objects. Data dictionaries are described as central sources of information that define and manage metadata. Domains specify value ranges for fields, while data elements describe field roles and semantics. Tables represent database tables, structures are like user-defined types, and views summarize distributed data. Search helps assist with searching and locks synchronize simultaneous data access. Common ABAP dictionary transactions and syntax for declaring variables and structures are also included.

1. Presented By
GOKUL

2. DATA
Data is information that has been translated into a
form that is efficient for movement or processing.
Metadata is data that describes other data.
METADATA

3. What is Data Dictionary?
• Data Dictionary is a central source of
information for the data in a information
management system.
• Its main function is to support the creation and
management of data definitions (or
"metadata").

4. OVERVIEW

5. Data Types
• Variables are nothing but reserved memory
locations to store values.
• You may like to store information of various
data types like character, integer, floating
point, etc.
• Based on the data type of a variable, the
operating system allocates memory and
decides what can be stored in the reserved
memory.

6. Elementary Data Types
• Byte
• Numeric
• Character-like
http://www.byte-notes.com/bit-byte-nibble-kilobyte

7. LENGTH & RANGE

9. • Domains
• Data elements
• Tables and structures
ABAP Dictionary 3 levels

10. Domains
• Describes the technical characteristics of a table
field
• Specifies a value range which describes allowed
data values for the fields
• Fields referring to the same domain (via the data
elements assigned to them) are changed when a
change is made to the domain
• Ensures consistency

12. DOMAIN VIEW

13. Data Elements
• Describes the role played by a field in a technical
context
• Fields of same semantic meaning can refer to the
same data element
• Contains the field information

15. Tables
• Represent the Database Tables where data
actually resides.
• Tables can be defined independently of the
database in the ABAP Dictionary.
• The fields of the table are defined with their
(database-independent) SAP ABAP data types
and lengths.

17. Structures
• Are record declarations that do NOT correspond to
a Database Table.
• Just like user-defined data type.
• Defined like a table and can then be addressed
from ABAP programs.
• Structures contain data only during the runtime of
a program.

18. Aggregated Objects Of ABAP Dictionary
• Aggregated means consisting of several
components.
• In the ABAP Dictionary, aggregated objects are
objects which come from several different
transparent tables.
• Views
• Search Help
• Lock Objects

19. Views
• Views in SAP _ ABAP are used to summarize data
which is distributed among several tables
• The data of a view is not actually physically
stored. The data of a view is instead derived from
one or more other tables
• It is tailored to the needs of a specific application

21. Search Help
• A Search help is a tool to help you search for data
records in the system
• An efficient and user-friendly search assists users
where the key of a record is unknown

22. Lock Objects
• Simultaneous accessing of the same data record by two users
in the SAP system is synchronized by a lock mechanism.
• Locks are set and released by calling certain function modules.
These function modules are generated automatically from the
definition of so-called lock objects in the ABAP/4 Dictionary
• Function modules :
Enqueue_<obj name> - to lock the table
dequeue_<obj name> - to release the lock

23. T-CODES
• SE11
• SE16N
• SE38

24. DECLARING A VARIABLE
Syntax:
DATA VARIABLE_NAME TYPE DATA_TYPE.
EXAMPLE:
DATA LV_VAR1 TYPE I.
DECLARING A INTERNAL TABLE
Syntax:
DATA INTERNAL_TABLE_NAME TYPE STANDARD TABLE OF TABLE_NAME.
EXAMPLE:
DATA LT_VBAK TYPE STANDARD TABLE OF VBAK.

25. DECLARING A STRUCTURE
Syntax:
TYPES BEGIN OF TYPE_NAME,
VARIABLE_NAME TYPE VARIABLE_TYPE,
VARIABLE_NAME1 TYPE VARIABLE_TYPE,
END OF TYPE_NAME.
EXAMPLE:
TYPES BEGIN OF TY_VBAK,
VBELN TYPE VBELN_VA,
NETWR TYPE NETWR,
END OF TY_VBAK.

26. THANK YOU