SAP ABAP Interview Questions

SAP is a type of software known as ERP (Enterprise Resource Planning) that large company use to manage their day to day affairs. ABAP (Advanced Business Application Programming) is the coding language for SAP to develop RICEFW objects. (Reports, Interfaces, Extensions, Forms and Workflows).

To describe the logical structures of the objects that are used in application development ABAP 4 data dictionary is used. It is also used to show the underlying relational database in tables.

Transparent tables: It has one to one relation with the table in the database. Its structure corresponds to single database field.

Pooled tables: It has many to one relation with the table in the database. Pooled tables are stored at the database level.

1. Basic List: For simple reports
2. Statistics: For Percentage, Average etc.
3. Ranked List : For analytical reports

It is an automatic procedure to transfer large or external data into SAP system. Queue file is the central component of the transfer, which receives the data through batch input programs and groups that are associated into sessions.

The data classes are classified into following classes

• Master Data: The data in this class seldom change
• Transaction Data: The data can be changed often in this class
• Organization Data: This data is a customized data and is entered in the system when the system is configured. It is rarely changed.
• System Data: This data is used by R/3 system itself

Internal table exists only when the program is run. It is used for performing table calculations on subset of database tables and also for re-organizing the content of database tables as per the users need.

There are 3 functional modules which are used in sequence to perform data transfer successfully using BDC programming. They are

1. BDC_OPEN_GROUP
2. BDC_INSERT
3. BDC_CLOSE_GROUP

To ensure the consistency of data, foreign keys are used. The relationship established between the tables and must be explicitly defined at field level. Data entered should be checked against the existing data to ensure that there is no contradiction. Cardinality has to be specified while defining foreign key relationship.

The difference between structure and table is

1. Data can be stored physically in Table, but a structure cannot
2. Structure does not have primary key but table can have
3. Table can have the technical attribute but the structure does not have

The data classes are divided into the following -

1. Master data - The data of this class rarely changes.
2. Transaction data - This type of data often changes.
3. Organization data - The data of this class also rarely changes. The data gets customized and gets entered into the configured system.
4. System data - R/3 system uses this data.

SAP R/3 mainly refers to the processing structure having three types of layers namely, Presentation layer, application layer, and database layer. It is generally considered to be Systems Application for processing of data.

For the development of traditional programs in R/3, ABAP is used. On the other hand, OOABAP is used for the development of BSP/PCUI applications.

The word buffer here refers to the memory area. The information about the table is found on the application server and this is the meaning of table buffer. In fact, even the data of the database table actually comes from the application server. Cluster table cant be buffeted but however, transparent and pool tables can be buffered.

The main difference between Template and Table is that the former one is dynamic in nature whereas the latter one is static in nature.

The resources of the applications of R/3 are managed with the help of SAP dispatcher which is basically a control agent.

The standard table of SAP can be modified mainly by two methods -

1. Customizing includes
2. Append structures

The following are the events associated with Screen Programming -

1. Process Before Output (PBO) - This event gets processed long before displaying the screen.
   
2. Process After Input (PAI) - This event is processed while the interaction of a user with the screen continues.
   
3. Process On Help (POH) - This even gets process on request by a user after pressing F1. The program gets appropriately coded in various event blocks. The present screen gets processed by the system.
4. Process On Value (POV) - This gets processed by pressing F4 by users. Here also, the coding can be done in the various event blocks.

The main events used for Logical Database are as follows -

• GET - The programs used for Logical Database ads executed with the help of this event. It mainly takes place when a line from the node was read by the logical database. This has made it very much available towards the program and GET statements determine the depth of the logical database.
• PUT - The flow of the program is directed by the PUT event.

While writing the code of HR-ABAP, End of the selection event can be used. Right at the beginning of the skeleton event, the data gets retrieved. Printing of the same data is done at the end of the selection event.

ALV is the abbreviation of Application List Viewer. ALV functions are provided by SAP in order for enhancing the report output. These function modules help in improving the readability and the functionality of the output report. Even the columns can be arranged with the help of this tool.

Dialog program is considered to be a module pool program while a report is considered to be an executable program. The execution is mainly done through a transaction. Screens can be customized with the help of Dialog programming.

The following are the data dictionary objects -

1. Tables
2. Domain
3. Views
4. Data Element
5. Search Helps or Matchcode Objects
6. Type Groups
7. Look Objects
8. Table Types
9. Structure

There are mainly two types of parameters -

1. Formal parameters - This is basically defined when the subroutine gets defined alongside FORM statement.
2. Actual parameters - This is defined when the subroutine gets defined alongside the PERFORM statement.

The following are the different types of database integrities -

1. Semantic Integrity
2. Primary Key Integrity
3. Relational Integrity
4. Value Set Integrity
5. Operational Integrity
6. Foreign Key Integrity

ABAP memory is considered to be the memory area included in the ABAP program available in the internal section or the roll area of the ABAP program. Data is stored in the program calls which allow the data to be passed from one program calls to another.

It is possible for data to be passed from one session to another with the help of using SAP Memory. All the sessions of SAPgui have accused to the memory area known as SAP Memory. Data can be very easily transferred from one session of the programming system to another

Function module exits will exist in some SAP application programs to allow a customer to add some functionality to the SAP program. Search the SAP application program globally looking for the following search string: “CALL CUSTOMER” to determine if an exit exists.

BADI stands for Business add-in. BADI’s are a relatively new enhancement concept that make use of ABAP Object technology. This is a true object oriented approach to SAP enhancements using classes, interfaces and methods to implement the BADI

In order to enhance a SAP application program, the BADI must first be defined. The developer will create an interface for the BADI. An adapter class is created from this that will implement the interface. Developers will then create an instance of the adapter class in the SAP application program and create method calls as required.

• Functional areas and user groups are organizational elements used in SAP Query that must first be created in order to user the query environment.
• The data that a query will be based on is defined in a functional area. A functional area is typically - based on a logical database but can be any table and fields within that table.
• Users are assigned to user groups. Functional areas are also assigned for the user group allowing users to create and start queries based on the data in that functional area. Multiple functional areas can be assigned to a user group and a functional area can be assigned to several different groups.

The first WRITE statement encountered in an ABAP program will trigger list processing. Upon completion of the program, the list is output. The system will generate some standard headings for list output that includes the program name and a page number in the heading.