LSMW-Interview Questions With Answers-SAP ABAP-1.


1. What Is LSMW All About?

LSMW is a tool provided by SAP in order to upload huge amount of data from legacy file to R/3 system. The Legacy System Migration Workbench (LSMW) is a tool to transfer data from legacy systems (Non SAP System) into an R/3 System (SAP System).

LSMW supports a step-by-step procedure; if one step is executed and saved then next step automatically follows.

Apart from creation of project/ subproject/ object and recording, there are 14 basic steps included in LSMW.

Through LSMW one can create Master data, create transactional data, modify existing master data etc. This tool is very useful when some mass changes are to be carried out and no standard SAP transactions are available for that.

There are few standard objects available in LSMW e.g. material master, vendor master, customer master, purchasing info record, purchase requisitions, purchase orders etc. Using these standard objects one can do mass data upload and mass transactions.

Apart from this LSMW provides another functionality of recording the transaction and then carrying that out many times with large data. Examples are mass deletion of purchase requisitions, mass deletion of planned orders etc.


2. State The Difference Between LSMW and BDC?
  • LSMW is basically designed for functional consultants who do not do much coding but need to explore the functionality while BDC is designed for a technical consultant.
  • LSMW offers different technique for migrating data: Direct input, BAPI, I-Doc, Batch input recording while BDC basically uses recording.
  • LSMW mapping is done by SAP while in BDC we have to do it explicitly.
  • LSMW is basically for standard SAP application while BDC basically for customized application.
  • Coding can be done flexibly in BDC when compared to LSMW.

3. When Should We Prefer Using LSMW Over Other Legacy Data Transfer Methods?
  • In case if you trust the data in the flat file and know there is not much coding to be done, then we can use LSMW. On the other hand if there is a lot of validations to be done go for BDC.
  • Also LSMW can be preferred for uploading Master Data records and standard SAP applications. Since LSMW is a tool and generally it makes use of standard program/objects, the execution would be faster, and less effort is needed to upload master data.

4. What Are The Advantages Of LSMW?
  • It's a code free tool (however if required coding can be done) - Therefore it helps functional people to upload data from legacy to SAP system.
  • Since it's an uploading tool provided by SAP, it has a structured way of working. You will have to finish every step before starting the next step.
  • Since it is integrated in R/3 it is independent of individual platform. The entire project can be downloaded and uploaded in any environment unlike BDC which has to be developed in development server and then transported to Production Server.
  • It can be preferred when there is a need to upload large volume of data.
  • It is preferred only if there is a requirement for one time transfer of data.

5. What is The Disadvantages Of LSMW?

LSMW is not suitable for frequent data transfer as there are a number of steps that are to be repeated every time.


6. What Are The Import Methods Available In LSMW? State the Advantage & Disadvantage Of Each Method?

There are four standard import methods available in LSMW.

IDOC's:
  • Advantages: Fast to load, easy processing, low programming for standard IDOC’s.
  • Disadvantages: Good knowledge of IDOC processing required, time consuming if changes have to be made to a created IDOC.

BAPI’s:
  • Advantages: Fast to load, easy processing, logical interface for functional/end user based on the business processes involved.
  • Disadvantages: Not always complete with all input fields of a transaction.

STANDARD/DIRECT INPUT:
  • Advantages: Well tested method, Fast to load, easy processing.
  • Disadvantages: No enjoy transactions, not always complete with all input fields of a transaction.

BATCH INPUT:
  • Advantages: Easy modifiable, all fields are available, easy re-processing.
  • Disadvantages: Comparatively slow, to use new screens or tabs a new recording has to be created, not easily usable for enjoy transactions, dependent on user settings, difference in foreground and background processing may occur.