What is BDC?

Batch Data Communication or BDC is a batch interfacing technique that SAP developed.  It is mainly used for uploading data into the SAP R/3 system.   BDC works by simulating the user input from transactional screen via an ABAP program.

The data input data file will come in the form of a flat file which the user save as file type txt file or prn file from the Microsoft Excel program.  An Abaper will create a program to read the text file and upload into the SAP system.

Normally, the tcode SHDB will be used to record the transaction code the user used.  After, the simulation, the Abaper can generate a sample program and modify from there.  It makes the programming easier and faster. 

Interview Questions on BDC

Q. What is BDC- its use, and how to use it?

It is Batch Data conversion used for transferring some data other than sap into sap ... this is also a work of an ABAPer.
     
Q. What is "UTS" Or may be it is "UST", something called Unit test?

Use:  After developing any object we should write a test case proving that the object is working properly or not.  This is done by the ABAPer. This is UNIT TEST CASE.

Q. In BDC how can we handle Table Controls?

When you do your recording you will have a tab for Next line or Insert. You have to capture that in your recording. If your transaction code doesn't have that in the recording then you have to set up a page down (=P+) and loop it based on the line entries u c on teh screen. 

Q. Suppose we are transfer data through BDC from leagacy to SAP and their is some duplicate data in legacy system but we don't want this in SAP system .So how can we check that this data is already exist? 

In BDC you would have all your legacy data in an internal table. Use Delete Adjacent dulpicates syntax to delete duplicate entries.

Q. Can we use two transaction code in one BDC like XK01 & XD01 if yes how?

Yes, we can do that by combining the two bdc program codes together.  Then you perform the program routine accordingly.  However, it will make your BDC program very long and complex.

Q. How can we handle errors in Function Module?

Exceptions is used to handle errors.

Q. Can we use Session method & Call transaction both in one BDC if yes please give me example and scenerio where we use this?

You start your dataload using Call Transaction and if any errors occur push all those errors in a session so that your dataload takes place uninterrupted and you can processs ur errors later.