LSMW_ Ppt by Mallik

LEGACY SYSTEM MIGRATION

WORKBENCH <LSMW>Mallikarjuna G

November 16, 2010

<LSMW> LEGACY SYSTEM MIGRATION WORKBENCH

LSM Workbench: What is it? • The LSMW is an R/3-based tool that supports us when transferring data

from non-SAP systems (Legacy Systems) to SAP systems once or periodically. It is a cross-platform component of the SAP system.

The Main functions of the LSMW are…

1. Import data from a legacy system ( legacy data in spreadsheet tables and/or sequential files).

2. Converting data from its original (legacy system) format to the target (SAP) format

3. Importing the data using the standard interfaces of SAP (IDoc inbound processing, batch input, direct input)

Legacy System Migration Workbench

Significance of Data Migration

Managing large amounts of data can be a significant challenge to most organizations. Some of the common data management tasks include:

•Data migration, e.g., loading legacy systems data into SAP applications during initial SAP implementation or M&A activity (mergers and acquisitions ).

• Data maintenance, e.g., mass changes to SAP data for price changes and payroll changes

• Data integration, e.g., loading vendor invoices or bank statements into SAP applications

• Mass data creation, e.g., creating new master data (materials, vendors, customers, etc.), or transactional data (journal vouchers, invoices, etc) in SAP systems.

Principles of the LSM Workbench


The quality and consistence of the data imported into R/3 should be more important than speed and performance of data migration.

Existing knowledge and coding should be used.

The developed ”mapping" and rules should be reusable and thus be used repeatedly in projects.

• Make sure that SAP customizing is finished.

• Determine the data contained in your legacy system and which of the data will be required in thefuture (with respect to business operation).

• Decide whether it makes sense to use this tool with respect to the data volume to be transferred. Itmay be easier to transfer very small data volumes into the SAP system manually. In the case of avery large data volume, batch input or IDoc techniques may cause extremely long runtimes.

• Run the relevant transaction in the SAP system manually with test data from the legacy systemand see which fields must be filled. There may be required fields that do not correspond to datafields in the legacy system. In such a case, you should better assign a fixed value or establish anoptional field for data transfer.

• • In which way will the data be extracted from the non-SAP system? Note: The LSMW does notextract data.

• In which form is the legacy data available? Determine accordingly which of the LSMW functionswill be applied.

• If only a part of your legacy system will be replaced by SAP, determine which function will beprovided by the SAP system and which by the legacy system.


Some of the Important Tips, before applying the LSMW tool


Features of LSMW

•LSMW is basically designed for a functional consultant who do not do much coding .

• The import technique to be used in an individual case, depends on the business object as well as on the availability of standard input programs

• Data consistency due to standard import techniques: Batch input Direct input BAPIs (Business Application Programming Interfaces) IDocs (Intermediate Documents)

• Structured way of working, because you have to finish every step before starting the next step

• LSMW is possible for only Standard transaction codes.

• Mapping is done by SAP itself.

• LSMW input file is always TEXT file.


Brief Description of Uploading methods

Batch Input: Uses classical BDC approach, but doesn't required an ABAP program to be written to format the BDC DATA. The user has to format the data using predefined structures and store it in a flat file. Yet it is a slower updation method.

Direct Input: Works similar to Batch Input programs. The difference is, instead of processing screens they validate fields and directly load the data into tables using standard function modules. Much faster and suits for large volume of data.

BAPI's : When the Data has to be distribute whith in the R/3.

ALE/IDOC : When the data has to be distribute with external system non-SAP or third party package.


Graphical representation

SAP AG July 1999 21

Accelerating Data Migration: LSM Workbench

One or severalfiles

R/3

Sta

nd

ard

Convert data

Batch Inputprocessing

Legacy dataon PC

Read data

Converteddata

Read dataLegacy data

on applicationserver

IDoc inboundprocessing

Direct Inputprocessing

How LSM Workbench works

Structurerelations

Field mapping

Conversionrules


Getting Started

Here is an example showing the way to use the conversion tool LSMW in SAP. It starts in the start-up screen of LSMW transaction and ends with a screen on which the results of the conversion are displayed

If you want to create or change objects, make sure that you are working in change mode. To activate this mode, click Change in the corresponding processing step. Only this mode provides all functions required for changing objects


Step 1 - Enter transaction LSMW


Step 2 – project, subproject, objects

At the initial screen, you can create a new project, corresponding subprojects and objects via Edit -> Create new entry. Alternatively you can select from an existing project

• Project: An ID with a maximum of 10 characters to name your data transfer project. If you want to transfer data from several legacy systems, you may create a project e.g. for every legacy system• Subproject: An ID with a maximum of 10 characters that is used as further structuring attribute• Object: An ID with a maximum of 10 characters to name the business object


Next Step : Execute

Once the project and subproject along with the object are determined we

execute to find the list of steps to be performed for data transfer


Process Steps

• The number of process steps is dynamic and shall depend on factors like input method

• By clicking the ‘User menu’ button one can select – deselect the Process steps

• To proceed through the processing steps one needs to start from the first one and execute each of them

• A step can be skipped by selecting the next available processing steps’ radio button


Step 1: Maintain object attributes

Choose if the data

transfer is once or periodic

Choose method for input of data.

In the method to input data from a BAPI, one needs to select the Business Object and the corresponding method.


Step 2: Maintain Source Structures

Give a name and a description to the source structure (Nothing but giving an Internal table name & description)

Source Structure


Step 3: Maintain Source Fields

In this step, you need to list what fields are present in the source structure. The easiest way is to click on ‘Table Maintenance’ icon to enter Fieldname, Type and Length for each field


Step 4: Maintain Structure Relations

Execute a step to ‘Maintain Structure Relations’. (See below Figure ) Since, there is only one Source and Target Structure, the relationship is defaulted automatically.


Step 5: Maintain field mapping and conversion rules

Select the Field (if the field is coming from Internal table, then click on ‘Source Field’ and select the field. Otherwise click on Rule Select the Radio Button ‘Constant’ and provide the Constant value . Eg. Like as ‘0004’.

Legacy System Migration Workbench Step 6: Maintain fixed values, translations, user-defined routines.

You can also maintain re-usable translations and user-defined routines, which can be used across conversion tasks. In this case, that step is not required.

Step 7: Specify Files.In this step, we define how the layout of the input file is. The input file is a [Tab] delimited with the first row as field names. It is present on my PC (local drive) as C:\XD02.txt. (Note: Just Execute->Click on change mode ->Save -> come back)

Legacy System Migration Workbench Step 8: Assign File

Execute step ‘Assign Files’ and the system automatically defaults the filename to the source structure(Note: Just Execute->Execute->back -> back)

Step 9: Read DataIn this step, LSMW reads the data from the source file (from your PC’s local drive). You have the option to read only selected rows and convert data values to Internal format.(Note: Just Execute->Execute->Back ->Back)

Step 10: Display Read Data

This step is optional. If required, you can review the field contents for the rows of data read(Note: Just Execute->Execute->Back )


Step 12: Display Converted Data

Step 11: Convert DataThis is the step that actually converts the source data (in source format) to a target format. Based on the conversion rules defined, source fields are mapped to target fields.(Note: Just Execute->Execute->back -> back)

Again this is an optional step to view how the source data is converted to internal SAP(Note: Just Execute->Execute->Back )

Step 13: Create batch input session

Once the source data is converted in an internal format, you can create a batch session to process updates (Note: Just Execute->Execute-)

Step 14: Run batch input session

You can execute the BDC session by Run Batch input session. Executing a batch input session is a standard SM35 transaction for managing BDC sessions. Once you have successfully executed the batch input session, the customer master records are updated in the system. You can confirm this by viewing the customer master records (XD03)


Events in LSMW

1. Global Data

2. Begin _ of _ Processing.

3. Begin _ of _ Transaction.

4. End _ of_ Transaction.

5. End _ of_ Processing.

Legacy System Migration Workbench Global Data

Global Data is used to Declare the variables, work area and Internal tables, which we need to implement the logic.

Begin _ Of_ ProcessingBegin _ of _ processing is an Event, which is triggered at the time of Processing of an Entire Flat File.

Begin _ Of_ TransactionBegin _ of _ transaction is an Event, which is triggered at Each record of Flat file.

End _ Of_ Transaction

End_ of _ transaction is an Event, which is triggered after completion of Each and Every record in the Flat file.

End _ Of_ Processing

End_ of _ processing is an Event, which is triggered after completion of Entire flat file processing.


X54321 MALLIK MK 123 ATPX54322 VENKAT VK 321 CHIX54323 Shiksha SS 456 ATPX54324 PRAVEEN PV 654 AMPX54321 SAILEELA SL 789 ATPX54322 MADHURI MD 987 KURX54323 ANUSHA AR 741 HYD

Begin _ of _ ProcessingBegin _ of _

Transaction

End _ of _ Transaction

End _ of _ Processing

THANK YOU.