SAP ABAP Interview Questions and Answers

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).

ABAP (Advanced Business Application Programming) is a high-level programming language created by the German software company SAP. It is currently positioned as the language for programming SAP’s Web Application Server, part of its NetWeaver platform for building business applications. Its syntax is somewhat similar to COBOL.

ABAP data dictionary is a central repository where all data descriptions, also known as metadata, are stored. The system ensures that there are no redundant data in the dictionary and makes the data available for all system components automatically.

The ABAP dictionary has several object types. They are

Tables- Represents DB tables where data is present

Types– This is defined globally and any change to type is automatically reflected in all the programs that make use of the same type

Views- Data is usually distributed among different tables. Views are used to summarize these

Lock Objects– These are used to synchronize simultaneous data access of the same data by different users

Domains: Domain is the central object for describing the technical characteristics of an attribute of a business object. It describes the value range of the field.

Data Element: It is used to describe these mantic definitions of the table fields like description the field. Data element describes how a field can be displayed to end-user.

A relationship which can be defined between tables and must be explicitly defined at field level. Foreign keys are used to ensure the consistency of data. Data entered should be checked against existing data to ensure that there is now contradiction. While defining foreign key relationship cardinality has to be specified. Cardinality mentions how many dependent records or how referenced records are possible.

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.

Basic List: For simple reports

Statistics:  For Percentage, Average etc.

Ranked List: For analytical reports

Transferring of large/external/legacy data into SAP system using Batch Input programming. Batch input is an automatic procedure referred to as BDC (Batch Data Communications). The central component of the transfer is a queue file which receives the data vie a batch input programs and groups associated data into “sessions”.

These are the 3functional modules which are used in a sequence to perform a data transfer successfully using BDC programming:

BDC_OPEN_GROUP – Parameters like Name of the client, sessions and user name are specified in this functional module.

BDC_INSERT – It is used to insert the data for one transaction into a session.

BDC_CLOSE_GROUP – This is used to close the batch input session.

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

Transparent Table: A transparent table contains only a single table. It has a 1-1 relation with the table in DB and stores data directly.  A single table can have either one or multiple primary keys. You can access them via native as well as open SQL. These tables are generally used to hold master data. It is possible to create secondary indexes in case of transparent tables.

Cluster Table: Instead of a single large table, cluster tables hold multiple small tables. The relationship is many to one in this case. Each table will have a primary key and it does not begin with the same fields. It’s not possible to create secondary indexes for cluster tables. They are used for performance improvement purposes such as when several tables have to be opened at the same time.

Pooled Tables: This is a combination of cluster and transparent data. This table is mainly used to store system data and contains data from a few large tables. The relationship here is again many-to-one as in cluster table. It is not possible to create secondary indexes and can be accessed only via open SQL. The primary key of each field begins with the same field as well.

Smart forms allow you to create forms using a graphical design tool.

For SAP, SAP scripts are a word processing tool. It has a function like standard text and layout sets. Its layout set consists of: Windows and pages, Character formats, Paragraph formats etc.

1. In ABAP dictionary, select object type Table, enter a table name and choose create
2. A field maintenance screen for the table is displayed. Table type Transparent table, set it as a default
3. Make the necessary entries in the short description and delivery classified on the Attributes page. Then define the fields of the table.
4. Proceed as when creating a transparent table. Now save your entries
5. Now choose EXTRAS Change table category
6. When a dialogue box appears, you have to select the table type ‘Pooled table’ or ‘Cluster table’
7. After selecting the table, return to the field maintenance screen for the table. Field pool or cluster name is displayed on the Attributes tab page in addition to the standard fields.
8. Now enter the name of the table cluster or table pool to which you want to assign the cluster table.

By using the loop event the reports output can be formatted

1. .at first
2. .at new
3. .at last

The difference between the table and template is that, table is a dynamic and template is a static.

ALV stands for Application List Viewer.  To enhance the output of the report, SAP provides a set of ALV function modules which can be used, and it also improves the functionality and readability of any report output.  It is an efficient tool used for arranging the columns in a report output.

End of the selection event is mostly used when we are writing HR-ABAP code.   In the HR-ABAP code, data is retrieved in the start of selection event and printing on the list and all will be done at the end of the selection event.

ABAP is used to develop traditional programs in R/3, while OOABAP is used to develop BSP/ PCUI applications and also anything that an involved object oriented like BADI’s and Smart Forms etc.

Over here, buffer means memory area, table buffer means the table information is available on the application server.  When you call data from database table, it will come from application server.  Transparent tables and pool tables are buffered, while cluster table cannot be buffered.

To format the ABAP code ‘pretty printer’ is used.

‘Type’:  You assign data type directly to the data object while declaring.

‘Like’:  You assign the data type of another object to the declaring data object.

‘Type’ refers the existing data type while ‘Like’ refers to the existing data object.

The 2 editors are SE38 and SE80 and both have the ABAP editor in place.   In SE38, you can create programs and view online reports and basically do all the development of objects in this editor.  In SE80, there are additional features such as creating packages, function group, module pool, classes, programs and BSP applications.

A report is an executable program; dialog is a module pool program. It has to be executed via a transaction only.  Dialog programming is used for customizations of screens.

To synchronize access of several users using same data Lock objects are used.

A cluster table contains data from multiple DDIC tables.  It stores data as name value pair.

To debug a script form, you have to follow

SE71–>give the form name->utilities->activate debugger

The different types of data dictionary objects are:

1. Tables
2. Views
3. Domain
4. Data Element
5. Type Groups
6. Search Helps/Match code Objects
7. Lock Objects
8. Structures
9. Table Types

Tuning can be done in three ways disk i/o, Sql tuning and memory tuning.  Before tuning, you have to get the status of your database using oracle utility called stat pack and tkprof.

To fetch the data from the table by the specified field Group by Clause is used.

A control agent referred as SAP dispatcher, manages resources for the R/3 applications.

There are two methods for modifying SAP standard tables

1. Append structures
2. Customizing includes

‘Database Index’ contains fields from one table while ‘Match Code’ contain fields from several tables. Match code objects can be built on cluster tables, transparent tables and pooled tables.

By using modularization techniques, you can avoid redundancy if the program contains the same or similar blocks of statements or it is required to process the same function several times.  By modularizing the ABAP/4 programs, we make them easy to read and improve their structure.  Modularized programs are also easier to maintain and update.

1. By defining Macros
2. By creating include programs in the library

The different types of parameters are

Formal Parameters:  It is defined during the definition of subroutine with the ‘FORM’ statement

Actual Parameters:  It is specified during the call of a subroutine with the ‘PERFORM’ statement

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

Macros can only be used in the program they are defined in and only after the definition are expanded at compilation / generation. Subroutines (FORM) can be called from both the program they are defined in and other programs. A MACRO is more or less an abbreviation for some lines of code that are used more than once or twice. A FORM is a local subroutine (which can be called external). A FUNCTION is (more or less) a subroutine that is called external. Since debugging a MACRO is not really possible, prevent the use of them (I’ve never used them, but seen them in action). If the subroutine is used only local (called internal) use a FORM. If the subroutine is called external (used by more than one program) use a FUNCTION.

Advantages:

• view is used to retrieve the data very fastly from the database tables
• memory wastage is reduced
• faster than joins to retrieve the data from database tables

Disadvantages:

• view is not a container, it will not hold the data
• view memory is not permanent memory

There are four types

1. function exit
2. menu exit
3. screen exit
4. field exit