Application Development Discussions
Join the discussions or start your own on all things application development, including tools and APIs, programming models, and keeping your skills sharp.
Showing results for 
Search instead for 
Did you mean: 

ABAP Questions

Former Member
0 Kudos

Hello all of you,

I am satish i have some Qs I dont know the proper Answers. so please any one answer to my Questions. those are very importent to me.

1. Define external layer.

2. What are control tables?

3. What is the function of the transport system and

workbench organizer?

4. What is a table pool?

5. What are pooled tables

6. What is a table cluster?

7. How can we access the correction and transport system?

8. Which objects are independent transport objects?

9. How is conversion of data types done between ABAP/4 & DB layer?

10. How is conversion of data types done between ABAP/4 & external level?

11. What are the Data types of the external layer?

those are the questions. Please answer those questions as soon as possible.

thanking you all,

by satish


Active Contributor
0 Kudos


Regarding pool and Cluster table:

Table Pools

The data is stored as a table pool in the database server which consists of

all the (physical) records from the tables present in that particular table pool.

Technically, The table name and the field name are the key fields in case

of pooled tables.

Table Clusters

Logical data records from different tables are stored as single PHYSICAL record

in the table clusters.

Technically. There can be n number keys (usually generated by the system ) for a

record in a cluster table and field called pageno is used to track the continuation

of the records.



Kindly reward points by clicking the star on the left of erply,if it helps.

Former Member
0 Kudos


For Que 7:

Correction system manages the internal system components like objects like only original version of the object exists. It stores all changes made to the object.

Transport system allows to transports the object from on SAP system to another (Development system to Production system). It allows to over write or delete existing object in target system and import new objects to target systems.

During development work we start by opening a task (correction) to which we can assign new and changed objects. Once changes have been made, transport new or changed objects to other SAP system by means of transport (Change) request.


If this helps u reward with points.

Former Member
0 Kudos

Pooled tables :

Pooled tables in the dictionary has a many-to-one relation with the table in database. Table in the database has the different name as in the dictionary.

A pooled table is used to combine several logical tables in the ABAP/4 dictionary. Pooled tables are logical tables that must be assigned to a table pool when they are defined.

Cluster tables:

Cluster table are logical tables that must be assigned to a table cluster when they are defined.

Cluster table can be used to store control data they can also used to store temporary data or text such as documentation

Transport system :

The Change and Transport System (CTS) is a tool that helps you to organize development projects in the ABAP Workbench and in Customizing, and then transport the changes between the SAP Systems and clients in your system landscape.

Workbench organiser :

Provides functions for organizing development programs . It is designed to support projects of all sizes.