14/11/2011

BDC Question And Answers

BDC Q & A

1.       What is full form of BDC Session ?
-      Batch Data Communications Session.

2.      What are the steps in a BDC session ?
-      The first step in a BDC session is to identify the screens of the transaction that the program will process. Next step is to write a program to build the BDC table that will be used to submit the data to SAP. The final step is to submit the BDC table to the system in the batch mode or as a single transaction by the CALL TRANSACTION command.

3.      How do you find the information on the current screen ?
-      The information on the current screen can be found by System à Status command from any menu.

4.      How do you save data in BDC tables ?
-      The data in BDC tables is saved by using the field name ‘BDC_OKCODE’ and field value of ‘/11’.

5.      What is the last entry in all BDC tables ?
-      In all BDC tables, the last entry is to save the data by using the field name BDC_OKCODE and a field value of ‘/11’.

6.      What is a multiple line field ?
-      A multiple line field is a special kind of field which allows the user to enter multiple lines of data into it.

7.      How do you populate data into a multiple line field ?
-          To populate data into a multiple line field, an index is added to the field name to indicate which line is to be populated by the BDC session (Line index ).

8.      Write the BDC table structure.
-      BDC table structure

      

       FIELD                                    TYPE                          DESCRIPTION

       Program                       CHAR(8)                    Program name of transaction
       DynPro                        CHAR(4)                    Screen number of transaction
       DynBegin                    CHAR(1)                    Indicator for new screen
       Fnam                           CHAR(35)                  Name of database field from Screen
       Fval                             CHAR(80)                  Value to submit to field

9.      Does the CALL TRANSACTION method allow multiple transactions to be processed by SAP ?
-      No. The CALL TRANSACTION method allows only a single transaction to be processed by SAP.

10.   Does the BDC_INSERT function allow multiple transactions to be processed by SAP ?
-      Yes.

11.   What is the syntax for ‘CALL TRANSACTION’ ?
-      CALL TRANSACTION trans [ using bdctab MODE mode ].
Three possible entries are there for MODE.
                               A         -           show all screens
                               E          -           show only screens with errors
                               N         -           show no screens

12.   Which mode of ‘CALL TRANSACTION’ method allows background processing ?
-      N is the only mode that allows background processing.

13.  Is it possible to use ‘CALL TRANSACTION’ without a BDC table ?
-      Yes, it is possible to use ‘CALL TRANSACTION’ without a BDC table. In such case, the current program is suspended, the transaction specified is brought up, and a user must enter the data into the screens.

14.  What is TCODE ?
-      TCODE is the transaction code for the transaction that should be used to process the data in the BDC table being inserted.

15.   What are the function modules that need to be called from BDC program to submit the transactions for processing ?
-      BDC_OPEN_GROUP
-      BDC_INSERT
-      BDC_CLOSE_GROUP

16.   How many sessions will be opened using BDC_OPEN_GROUP ?
-          Only one session can be created using the BDC_OPEN_GROUP functon.

17.  What is ‘BATCH INPUT’ or ‘BDC’ ?
-          The SAP system offers two primary methods (BDC SESSION METHOD, CALL TRANSACTION METHOD) for transferring data into the system from other systems and Non-SAP systems. These two methods are collectively called as ‘BATCH INPUT’ or ‘Batch Data Communication’ (BDC).

18.  What are the advantages in Batch Input ?
-          The Batch Input ensures Data integrity.
-          No manual interaction is required during Data transfer.

19.  What is the functionality of ‘Classical Batch Input’ ?
-          In ‘Classical Batch Input’ an ABAP/4 program reads the external data that is to be entered in the SAP system and stores the data in a Batch Input session. This session stores the actions that are required to enter your data using normal SAP transactions.

20.  Which Function Modules are used in ‘Classical Batch Input’ ?
-          BDC_OPEN_GROUP , BDC_INSERT, BDC_CLOSE_GROUP.

21.  Can we use the ABAP/4 dictionary to generate data structures for SAP tables with the programming languages ?
-          Yes, we can use COBOL, PL/1, AND ‘C’.

22.  What is the use of ‘Structure Identifiers’ in SAP ?
-          With ‘Structure Identifier’ we can generate a listing of all of the table fields that are required by the corresponding Batch Input program. We do not need to find out which tables are required for the Batch Input program and generate their structures individually.

23.  What is the use of RFC or CPI-C in SAP ?
-          With RFC or CPI-C we can transfer data between two R/3 systems.

24.  What is Synchronous Database update ?
-          During the processing no transaction is stored until the previous transaction has been written to the Database. This is called Synchronous Database update.

25.  What are the differences between CALL TRANSACTION and BATCH INPUT SESSION ?
-      The most important aspects of the batch session interface are:
-      Asynchronous processing
-      Transfers data for multiple transactions
-      Synchronous database update
During processing, no transaction is started until the previous transaction has been written to the database.
-      A batch input processing log is generated for each session
-      Sessions cannot be generated in parallel
The most important aspects of the CALL TRANSACTION USING interface are:
-      Synchronous processing
-      Transfers data for a single transaction
-      Synchronous and asynchronous database updating both possible
The program specifies which kind of updating is desired.
-      Separate LUW for the transaction
The system performs a database commit immediately before and after the CALL TRANSACTION USING statement.
-          No batch input processing log is generated

26.  What are the types of Batch Input ?
-          Classical Batch Input
-          Call Transaction
-          Call Dialog

27.  What is BDC_OKCODE ?
-          The command field is identified by a special name in batch input called BDC_OKCODE. This name is constant and always identifies the command field.

28.  How can we execute a function in a BDC session ?
-          We can execute a function in a transaction by entering the function code or function key number in the command field of an SAP session. A function key number must be prefixed with the / (slash) character. A function code must be prefixed with the = character. Example:
BDCDATA-FNAM = 'BDC_OKCODE'
BDCDATA-FVAL = '=UPDA'

29.  How can we position the cursor on a particular field ?
-          BDCDATA-FNAM = ‘BDC_CURSOR’
BDCDATA-FVAL = <FIELDNAME>

30.  Who are Dialog users and who are Background users ?
-          Dialog users are normal interactive users in the SAP system. Background users are user master records that are specially defined for providing authorizations for background processing jobs.

31.  What is the use of BDC_INSERT ?
-          We add a transaction to a Batch Input Session by using this function.

32.  What are the update modes in CALL TRANSACTION ?
-          S : Synchronous
-          A : Asynchrnous
-          L : Local

33.  What does the message parameter indicates ?
-          The message parameter indicates there all system messages issued during a CALL TRANSACTION are written into the internal table <itab>. The internal table must have the structure of BDCMSGCOLL.

34.  What is Direct Input ?
-          To enhance the batch input procedure, the system offers the direct input technique especially for transferring large amount of data. This technique doesn’t create sessions but stores the data directly. The direct input programs must be executed in the back ground only. To maintain and start these programs, use program RBMVSHOW or the transaction BMVO.

35.  What are the features of Recording Function ?
-          recording transaction runs
-          creating batch input sessions from the recorded transaction runs.
-          Generating a batch input program from the recorded data.

36.  What is synchrnous database update ?
-          During the processing, no transaction is stored until the previous transaction has been written to the database. This is called Synchronous database update.