what function does data dictionary perform

[Former Member]

what function does data dictionary perform

[Former Member]

Data definitions (metadata) are created and managed in the ABAP Dictionary. The ABAP Dictionary permits a central description of all the data used in the system without redundancies. New or modified information is automatically provided for all the system components. This ensures data integrity, data consistency and data security.

You can create the corresponding objects (tables or views) in the underlying relational database using these data definitions. The ABAP Dictionary therefore describes the logical structure of the objects used in application development and shows how they are mapped to the underlying relational database in tables or views.

The ABAP Dictionary also provides standard functions for editing fields on the screen, for example for assigning a screen field an input help.

The most important object types in the ABAP Dictionary are tables, views, types, domains, search helps and lock objects.

Tables are defined in the ABAP Dictionary independently of the database. A table having the same structure is then created from this table definition in the underlying database.

Views are logical views on more than one table. The structure of the view is defined in the ABAP Dictionary. A view on the database can then be created from this structure.

Types are used in ABAP programs. The structure of a type can be defined globally in ABAP programs. Changes to a type automatically take effect in all the programs using the type.

Lock objects are used to synchronize access to the same data by more than one user. Function modules that can be used in application programs are generated from the definition of a lock object in the ABAP Dictionary.

Different fields having the same technical type can be combined in domains. A domain defines the value range of all table fields and structure components that refer to this domain.

The ABAP Dictionary also contains the information displayed with the F1 and F4 help for a field in an input template. The documentation about the field is created for a data element that describes the meaning of the contents of a table field. The list of possible input values that appears for the input help is created by a foreign key or a search help.

Ckeck this link for any help:

ABAP in 21 days Book:

http://cma.zdnet.com/book/abap/ch03/ch03.htm

http://help.sap.com/saphelp_40b/helpdata/en/4f/991f82446d11d189700000e8322d00/applet.htm SAP Online Help For Dictionary.

Bellow links are for ABAP Dictionary

http://www.daneprairie.com/

http://www.sapbrainsonline.com/TUTORIALS/TECHNICAL/ABAP_tutorial.html

[Former Member]

Hi

In a data management system, the main functions performed by the data dictionary are as follows:

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.

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Thank You

Nikunj Shah

[Former Member]

hi,,..

PLZ REWARD IF USEFUL

ABAP Dictionary

Purpose

Data definitions (metadata) are created and managed in the ABAP Dictionary. The ABAP Dictionary permits a central description of all the data used in the system without redundancies. New or modified information is automatically provided for all the system components. This ensures data integrity, data consistency and data security.

You can create the corresponding objects (tables or views) in the underlying relational database using these data definitions. The ABAP Dictionary therefore describes the logical structure of the objects used in application development and shows how they are mapped to the underlying relational database in tables or views.

The ABAP Dictionary also provides standard functions for editing fields on the screen, for example for assigning a screen field an input help.

What Information is Stored in the ABAP Dictionary?

The most important object types in the ABAP Dictionary are tables, views, types, domains, search helps and lock objects.

Tables are defined in the ABAP Dictionary independently of the database. A table having the same structure is then created from this table definition in the underlying database.

Views are logical views on more than one table. The structure of the view is defined in the ABAP Dictionary. A view on the database can then be created from this structure.

Types are used in ABAP programs. The structure of a type can be defined globally in ABAP programs. Changes to a type automatically take effect in all the programs using the type.

Lock objects are used to synchronize access to the same data by more than one user. Function modules that can be used in application programs are generated from the definition of a lock object in the ABAP Dictionary.

Different fields having the same technical type can be combined in domains. A domain defines the value range of all table fields and structure components that refer to this domain.

The ABAP Dictionary also contains the information displayed with the F1 and F4 help for a field in an input template. The documentation about the field is created for a data element that describes the meaning of the contents of a table field. The list of possible input values that appears for the input help is created by a foreign key or a search help.

Integration in the ABAP Workbench

The ABAP Dictionary is completely integrated in the ABAP Workbench. The R/3 System works interpretatively, permitting the ABAP Dictionary to be actively integrated in the development environment. Instead of the original objects, the interpreters see only internal representations of these objects.

These internal representations are adjusted automatically when the system finds that changes have been made in the ABAP Dictionary. This ensures that the screen and ABAP interpreters, input help, database interface, and development tools always access current data.

The following ABAP program lists the airline carriers (see Flight model) and carrier IDs contained in table SCARR.

DATA: SCARR_TAB TYPE SCARR.

SELECT * INTO SCARR_TAB FROM SCARR.

WRITE: / SCARR_TAB-CARRID, SCARR_TAB-CARRNAME.

ENDSELECT.

Only structure SCARR_TAB is declared in the program. All the information about this structure, such as the field names, data types and field lengths, are copied from table SCARR, which is defined in the ABAP Dictionary. This information about table SCARR is called from the ABAP Dictionary when the program is generated.

This means that the source text of the program need not be adjusted when a change is made to table SCARR, for example when the length of a table field is changed. The next time the program is called, the system automatically determines that the structure of table SCARR has changed. The program is simply regenerated, thereby retrieving up-to-date information about table SCARR from the ABAP Dictionary.

N.REKHA

[prasanth_kasturi]

hi,

Data definitions (metadata) are created and managed in the ABAP Dictionary. The ABAP Dictionary permits a central description of all the data used in the system without redundancies. New or modified information is automatically provided for all the system components. This ensures data integrity, data consistency and data security.

You can create the corresponding objects (tables or views) in the underlying relational database using these data definitions. The ABAP Dictionary therefore describes the logical structure of the objects used in application development and shows how they are mapped to the underlying relational database in tables or views.

The ABAP Dictionary also provides standard functions for editing fields on the screen, for example for assigning a screen field an input help.

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prasanth

[Former Member]

Hello Srikanth,

ABAP Data Dictionary centrally describes and manages all the data definations used in the system. The ABAP dictionary is completly integrated in the ABAP workbench. All the other components of the workbench can actively access the definations stored in the ABAP dictionary.

-> AS name describes, it acts as a dictionary for all the components which are rellated to SAP.

For more detailed description, go through the link provided below :

http://abaptutorial.blogspot.com/2006/01/abap-data-dictionary.html

http://help.sap.com/saphelp_nw04/helpdata/en/cf/21ea31446011d189700000e8322d00/content.htm

http://www.sapbrainsonline.com/TUTORIALS/default.html

FAQ's on DATA DICTIONARY :

http://www.sapbrainsonline.com/FAQs/TECHNICAL/SAP_ABAP_DATADICTIONARY_FAQ.html

Go through all these links / go through the SAP Help link...U will find lot of useful information.

Have a great day!

Regards,

Krishna Chaitanya

[Former Member]

hi there..

following are the main functions of data dictionary::

Central information repository for application and system data. The ABAP Dictionary contains data definitions (metadata) that allow you to describe all of the data structures in the system (like tables, views, and data types) in one place. This eliminates redundancy.

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[Former Member]

Hi Friend,

if u want to become a familiar in abap dictionary first of all u can read abap 21 days..In Interview point of view also it is enough ...

Regards,

Bixamaiah.

[Former Member]

hi,

A data dictionary is a centralized storage location for information about the data that is stored in a database. This information is often called “metadata” (data about data).

The ABAP Dictionary :

Enforces data integrity

Manages data definitions without redundancy

Is tightly integrated with the rest of the ABAP Workbench

When a dictionary object is changed, a program that references the changed object will automatically reference the new version the next time the program runs. Because ABAP is interpreted, it is not necessary to recompile programs that reference changed dictionary objects.

The basic objects of ABAP Dictionary are Tables , Data elements and Domains.

[manubhutani]

Hi

data integrity

Manages data definitions without redundancy

integration with workbench

please reward points

[Former Member]

Hi Sreekanth,

ABAP Dictionary is a repository that contains defininitions of all the data objects that we create in SAP R/3 and to ensure data consistency & data integrity.

There are six objects in ABAP Dictionary.

1.Structure: Group of related components.

2.View:It contains set of fields or columns from one or more tables

3.Lock Object: Using this lock the object to ensure data security.

4.Type group:Using this we can define user defined data types in addition to the built in data types.

5.Onlinehelp: It enables to define the documentation for the table fields.

6.Searchhelp:It displays the list of input values for a field.

we can define & assign to the field.

In dictionary we can create tables using Database Table.

In creation of tables we have DOMAIN and DATAELEMENT.

We can define characteristics of field there itself or

we can assign the domain to dataelement and dataelement to a field of table

Dataelement defines the characterstics of a field like datatype,length,decimal length(these are technical characteristics)short description,fieldlabel and documentation.

Domain is parent for dataelement it has data type,length and decimal length.It defines the value range.

Reward points if useful...

[Former Member]

Hi Sreekanth,

ABAP Dictionary is a repository that contains defininitions of all the data objects that we create in SAP R/3 and to ensure data consistency & data integrity.

There are six objects in ABAP Dictionary.

1.Structure: Group of related components.

2.View:It contains set of fields or columns from one or more tables

3.Lock Object: Using this lock the object to ensure data security.

4.Type group:Using this we can define user defined data types in addition to the built in data types.

5.Onlinehelp: It enables to define the documentation for the table fields.

6.Searchhelp:It displays the list of input values for a field.

we can define & assign to the field.

In dictionary we can create tables using Database Table.

In creation of tables we have DOMAIN and DATAELEMENT.

We can define characteristics of field there itself or

we can assign the domain to dataelement and dataelement to a field of table

Dataelement defines the characterstics of a field like datatype,length,decimal length(these are technical characteristics)short description,fieldlabel and documentation.

Domain is parent for dataelement it has data type,length and decimal length.It defines the value range.

Reward points if useful...