topic diff between BDC and LSMW in Application Development and Automation Discussions

diff between BDC and LSMW

Former Member — Tue, 20 Nov 2007 15:01:21 GMT

hai gurus

wat is the diff between BDC and LSMW?where can i use batch input and standard input?

Re: diff between BDC and LSMW

Former Member — Tue, 20 Nov 2007 15:33:48 GMT

Hi,

BDC - besides the literal meaning (Batch data communication) - usually refers to the procedure where u record a process (transaction) and then run it numerous times while changing the data each run in order to enter the system large amounts of data (batches) but still avoid doing it manually. In this method there is a process that does the same as was recorded - goes through all the screens and fills the fields with data, very much like doing it online only much quicker.

LSMW is a tool with the same purpose - enter the system large amounts of data, only it has some options of how to do it: one of them is batch input recording, which is exactly like BDC, but there are also standard batch or direct input, BAPI and IDoc. LSMW also gives a very nice frame of how to develop the complete process step by step - starting with reading the data files in the right structure and ending with monitoring the number of successful entries in the system, which u have to develop in code writing in BDC.

Hopes this helps (pls reward points if so)

Igal

Re: diff between BDC and LSMW

Former Member — Tue, 20 Nov 2007 18:01:41 GMT

hi,

where can i use batch input and standard input?

Batch Input

With the Batch Input method, an ABAP program reads the external data that is to be entered in the R/3 System and stores the data in a “batch input session”. The session records the actions that are required to transfer data into the system using normal SAP transactions.

When the program has generated the session, you can run the session to execute the SAP transactions in it. You can explicitly start and monitor a session with the batch input management function (by choosing System - Services - Batch Input), or have the session run in the background processing session.

It offers management of sessions, support for playing back and correcting sessions that contain errors, and detailed logging. Your program prepares the data and stores it in a batch input session. A session is a collection of transaction data for one or more transactions. Batch input sessions are maintained by the system in the batch input queue. You can process batch input sessions in the background processing system.

Your program must open a session in the queue before transferring data to it, and must close it again afterwards. All of these operations are performed by making function modules calls from the ABAP program.

The most important aspects of the session interface are:

Asynchronous processing

Transfer 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 batch input program must not open a session until it has closed the preceding session.

Direct Input (DINP)

With direct input, the SAP function modules execute the consistency checks. However with batch input, these consistency checks are executed with help of the screens. This means that direct input has considerable performance advantages. But there are a few programs for direct input, you can use them if it accomplishes your goal. Direct Input programs work like that they update database tables directly. As you know that it is forbidden to update SAP database tables directly, since consistency and security should be considered. Exceptions are these direct input programs. So you are not able to write custom ABAP direct input programs. But of course you can write ABAP programs to update custom database tables (Z tables), if you are sure all about consistency.

So why SAP has created direct input programs? Because SAP wanted to enhance the batch input procedure, since batch input is slower. SAP offers the direct input technique, especially for transferring large amount of data. In contrast to batch input, this technique does not create sessions, but stores, updates, inserts data directly. To enter the data into the corresponding database tables directly, the system calls a number of function modules that execute any necessary checks. In case of errors, the direct input technique provides a restart mechanism. However, to able to activate the restart mechanism, direct input programs must be executed in the background only. To maintain and start these programs, use program RBMVSHOW or transaction BMV0.

Reward if this helps you.

siva

Re: diff between BDC and LSMW

Former Member — Wed, 21 Nov 2007 08:36:29 GMT

Main reasons for LSMW

Data transfor to be same for LSMW & BDC But LSMW for ERROR handling very crtical, all going for BDC and valdition checking very crtical.

LSMW is mainley used for Master Data Transation onley.

BDC Automaticalley provided for ERROR logs. So easely handling Error handling and valdition checking also. All clients will be accept for BDC.

Right now onley prefer for BAPI's

Re: diff between BDC and LSMW

Former Member — Wed, 21 Nov 2007 08:42:50 GMT

main diff

LSMW offers different technique for migrating data: Direct input, BAPI, Idoc, Batch input recording. While BDC basically uses batch input sessions and CALL TRANSACTION method.

Limit on number of records which can be uploaded in one session of BDC (999 records). No such limit in LSMW.

LSMW is more to do with configuration while BDC involves programming.

3. 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.

4. 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, dependant on user settings, difference in foreground and background processing may occur.

Use the CALL TRANSACTION USING statement

Summary: With CALL TRANSACTION USING, the system processes the data more quickly than with batch input sessions. Unlike batch input sessions, CALL TRANSACTION USING does not automatically support interactive correction or logging functions.

Your program prepares the data and then calls the corresponding transaction that is then processed immediately.

The most important features of CALL TRANSACTION USING are:

Synchronous processing

Transfer of data from an individual transaction each time the statement CALL TRANSACTION USING is called

You can update the database both synchronously and asynchronously

The program specifies the update type

Separate LUW (logical units of work) for the transaction

The system executes a database commit immediately before and after the CALL TRANSACTION USING statement

No batch input processing log

Create a session on the batch input queue.

Summary: Offers management of sessions, support for playing back and correcting sessions that contain errors, and detailed logging.

Your program prepares the data and stores it in a batch input session. A session is a collection of transaction data for one or more transactions. Batch input sessions are maintained by the system in the batch input queue. You can process batch input sessions in the background processing system.

Your program must open a session in the queue before transferring data to it, and must close it again afterwards. All of these operations are performed by making function module calls from the ABAP program.

The most important aspects of the 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 batch input program must not open a session until it has closed the preceding session.

Hope this is helpful, DO reward.

Re: diff between BDC and LSMW

Former Member — Wed, 21 Nov 2007 14:02:32 GMT

hai sivakumar

can u give me the advantage of BDC over LSMW?

Re: diff between BDC and LSMW

Former Member — Wed, 21 Nov 2007 14:07:48 GMT

Hi,

Go through this link, will get some info on advantages of BDC over LSMW.

eg: Use BDC when handling table control. etc.

Reward points if this helps.

Manish

Re: diff between BDC and LSMW

Former Member — Wed, 21 Nov 2007 14:11:46 GMT

BDC is just one of several methods to upload data the LSMW tool is using. With LSMW you do very little programming because staff like handling the input file is done by the lsmw, therefore lsmw creates a text file in the format needed by the standard program and create a bdc to be run via sm35

Re: diff between BDC and LSMW

Former Member — Wed, 21 Nov 2007 18:56:31 GMT

LSMW very useful for migrating master data .

the programming effort is less when compared to BDC.

BDC we can handle several exceptions there are several transactions where in they are table controls,only with the proper designing of the flat file the best use of the tool can be made.and the error handling methods are available.