Zusammenfassung der Ressource
ABAP Dictionary
- Activities
- Create user-defined types, such as data
elements, structures, and table types, for use
in ABAP programs or in interfaces of function
modules, object methods, and so on
- Create the database objects such as tables,
indexes, and views in the ABAP Dictionary
- Provides a number of services that support
program development. For example, the
ABAP Dictionary supports setting and
releasing locks. defining an input help, and
attaching a field help to a screen field.
- functions
- Define the tables and database views. the
system creates these tables and views in the
underlying database with the definition in
ABAP Dictionary. Changes to the definition
of a table or database view are also
automatically made in the database.
- Define indexes in the ABAP Dictionary to
speed up access to data in a table. the
system also creates these indexes in the
database when the table is activated.
- Categories
- Data
elements
- Structures
- Deep
Structures
- contains a least
one field with a
table type
- Nested
Structures
- structures that
include another
structures
- Include
Structures
- mechanism exits to
avoid redundant
structures
- Table types
- Transparent Tables
- Fragmentation in tables
- Fragmented Indexes
- delete and create the indexes again
- Fragmented tables
- to reduce fragmentation you have to convert the table
- Size Category
- expected storage
requirements
- Data Class
- Master Data
- data that is seldom modified
- Transaction Data
- data that is frequently modified
- Organizational data
- data you can define when you
customize and install the system
- System data
- Data that SAP systems need
- WARRING: defines which tablespace is
use for a specific table
- data modifications LOG (SCU3)
- Cluster Tables
- store functionally depend data. the intersection of the key fields of the cluster tables form the key of the
table cluster, knows as the cluster key and stored in the VARDATA field. PAGNO field guarantees the
uniqueness within the table cluster. TIMESTAMP and PAGELG fields contains administrative informtation
- Pooled Tables
- stores data records from the tables defined in the ABAP Dictionary that are not dependent on one
another. combine small SAP tables in on database table. TABNAME field is the name of the pooled table.
VARKEY field consists of the concatenation of key fields of the pooled table. DATALN field store the lenght
of the VARDATA. VARDATA stores the non-key.fields of the pooled tables.
- services support
program
development
- input helps for secreen fields
- Field help for screen fields
- input check
- Set and release locks
- Data buffering
- Logging
- Others
- Domains
- WARRING: Domains manage the technical
properties of data elements centrally. They cannot
be used directly in programs, tables, and so on
- Types Groups
- can be used to define tour own global,
complex data types and global constants.
the are obsolete since release 4.5a.
- WARRING: the name of the
type group can contain a
maximum of five characters.
- STATMENT : Type-POOL and
the name of data types and
constants begins with zmytp_