what is batch data communication?

[Former Member]

hi all,

please tell what is batch data communication ?

[Former Member]

Hi,

BDC allows you to perform database updates in the background using standard SAP transactions. The resultant entries will be as if the user had manually entered the data via SAP. This means that you do not bypass any of the standard SAP consistency checks, authorisations etc. There are two main methods of ABAP BDC, these are Call Transaction and Batch Input. Other methods of update include Direct update, Idoc and BAPI. Format date field for BDC screen entry

call transaction:

http://www.sapdevelopment.co.uk/bdc/bdc_call.htm

rgds,

bharat.

[arvind_pereira]

This link has been moved buddy

[former_member699750]

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.

we will use BDC in two methods..

Session method.

1) synchronous processing.

2) can tranfer large amount of data.

3) processing is slower.

4) error log is created

5) data is not updated until session is processed.

Call transaction.

1) asynchronous processing

2) can transfer small amount of data

3) processing is faster.

4) errors need to be handled explicitly

5) data is updated automatically

reward if useful

Regards

Sugumar G

Edited by: Sugumar Ganesan on Apr 3, 2008 7:04 AM

Edited by: Sugumar Ganesan on Apr 3, 2008 7:05 AM

[prasanth_kasturi]

What is BDC

BDC ( Batch Data Communication ) is used for uploading mass data into SAP system. In SAP system BDC also referred to batch input or data tranfer.

Typical Uses

Typical uses of batch input include the one-time import of data from a legacy system into a newly installed R/3 System. Another typical use is for periodic transfers of data from external systems or legacy systems that are still in use into SAP.

Background of BDC

To ensure data consistency in SAP system, we must not update SAP data directly from ABAP program. We must upload data through similar program flow compared to manual input by user. SAP provide this by BDC. BDC works by simulating the user input from transactional screen via an ABAP program. This means that you do not bypass any of the standard SAP consistency checks, authorisations, update conjunction tables, etc.

How it works

Data input entered by user simulated in BDC by data packet. The transaction then started using this internal table as the input and executed in the background.

Data packet is an internal table has a structure of BDCDATA, it has fields:

1. PROGRAM (program name)

2. DYNPRO (screen number)

3. DYNBEGIN (New screen start) X=new screen

4. FNAM (Field name)

5. FVAL (Field value)

Data packet contain of screen by screen packets. One screen packet contain:

1. Screen no

2. Cursor position

3. User command

4. Input fields

It implemented in internal table in this format:

PROGRAM DYNPRO DYNBEGIN FNAM FVAL

program1 screen1 X

BDC_CURSOR pos1

BDC_OKCODE comm1

fieldname1 fieldvalue1

fieldname2 fieldvalue2

program2 screen2 X

BDC_CURSOR pos1

BDC_OKCODE comm1

fieldname1 fieldvalue1

fieldname2 fieldvalue2

For example, we want to create a BDC to change ABAP program title.

Here is what we do manually: Go to screen SE38, enter program, select radiobutton "Attributes", then click "Change". After that, change title then press "Save" button.

In BDC, we simulate this by following internal table:

PROGRAM DYNPRO DYNBEGIN FNAM FVAL

SAPLWBABAP 100 X

BDC_CURSOR RS38M-FUNC_HEAD

BDC_OKCODE =CHAP

RS38M-PROGRAMM ZAALTESTBDC

RS38M-FUNC_EDIT

RS38M-FUNC_HEAD X

SAPLSEDTATTR 200 X

BDC_CURSOR RS38M-REPTI

BDC_OKCODE =CONT

RS38M-REPTI Test change title BDC

TRDIR-SUBC 1

TRDIR-FIXPT X

SAPLWBABAP 100 X

BDC_CURSOR RS38M-PROGRAMM

BDC_OKCODE =BACK

RS38M-PROGRAMM ZAALTESTBDC

RS38M-FUNC_HEAD X

To accomodate you to build data packet, SAP provide BDC recording in tcode SHDB.

Do following action:

1. Go to tcode SHDB

2. click "New recording", enter recording name to identified your record, and TCode to be recorded.

3. You will enter recording mode of the transaction, simulate action you want to perform in this transaction

4. At the end it will result internal table ready to upload to data transfer methods (Call transaction or BDC sessions).

After internal table created then we pass this to data transfer methods. There are two alternatives of data transfer methods, using Call Transaction or BDC session.

Call transaction performed by calling command ‘Call Transaction’. ABAP program must do the error handling based on returning table from call transaction command. It is used for real-time interfaces and custom error handling & logging features. This is suitable when processing sequential update, it means, next data will depend on previous data.

In BDC Sessions, the ABAP program creates a session with all the transactional data, and this session can be viewed, scheduled and processed (using Transaction SM35) at a later time. The latter technique has a built-in error processing mechanism too.

reward if helpful

regards

prasanth

[Former Member]

Hi Sanjay,,,,,,,

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.

Check this links where you can get lots of information on BDC ,,,,

http://www.sap-img.com/bdc.htm

http://www.sapbrainsonline.com/TUTORIALS/TECHNICAL/BDC_tutorial.html

http://aspalliance.com/1130_Batch_Data_Communication_BDC_in_SAP_R3

http://abap-gallery.blogspot.com/2007/08/bdc-batch-data-communication-tutorial.html - 61k -

Please Reward if found useful........

Regards ,,

Sreekar.K

[Former Member]

Hi,

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.

Go throgh this link....

http://www.sap-img.com/abap/learning-bdc-programming.htm

http://abap-gallery.blogspot.com/2007/08/bdc-batch-data-communication-tutorial.html

http://sapabap.iespana.es/sap/info/bdc/bdc01.htm

if its useful reward points

[Former Member]

Batch Data Communication

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.

Chk this..

BDC or Batch Input Program Tips and Tricks

http://www.sap-img.com/bdc.htm

Batch Data Communication (BDC) in SAP R/3

http://aspalliance.com/1130_Batch_Data_Communication_BDC_in_SAP_R3

[Former Member]

hi

SESSION METHOD

About Session method

In this method you transfer data from internal table to database table through sessions.

In this method, an ABAP/4 program reads the external data that is to be entered in the SAP System and stores the data in session. A session stores the actions that are required to enter your data using normal SAP transaction i.e., Data is transferred to session which in turn transfers data to database table.

Session is intermediate step between internal table and database table. Data along with its action is stored in session i.e., data for screen fields, to which screen it is passed, the program name behind it, and how the next screen is processed.

When the program has finished generating the session, you can run the session to execute the SAP transactions in it. You can either explicitly start and monitor a session or have the session run in the background processing system.

Unless session is processed, the data is not transferred to database table.

BDC_OPEN_GROUP

You create the session through program by BDC_OPEN_GROUP function.

Parameters to this function are:

• User Name: User name

• Group: Name of the session

• Lock Date: The date on which you want to process the session.

• Keep: This parameter is passed as ‘X’ when you want to retain session after

processing it or ‘ ‘ to delete it after processing.

BDC_INSERT

This function creates the session & data is transferred to Session.

Parameters to this function are:

• Tcode: Transaction Name

• Dynprotab: BDC Data

BDC_CLOSE_GROUP

This function closes the BDC Group. No Parameters.

Some additional information for session processing

When the session is generated using the KEEP option within the BDC_OPEN_GROUP, the system always keeps the sessions in the queue, whether it has been processed successfully or not.

However, if the session is processed, you have to delete it manually. When session processing is completed successfully while KEEP option was not set, it will be removed automatically from the session queue. Log is not removed for that session.

If the batch-input session is terminated with errors, then it appears in the list of INCORRECT session and it can be processed again. To correct incorrect session, you can analyze the session. The Analysis function allows to determine which screen and value has produced the error. If you find small errors in data, you can correct them interactively, otherwise you need to modify batch input program, which has generated the session or many times even the data file.

CALL TRANSACTION

About CALL TRANSACTION

A technique similar to SESSION method, while batch input is a two-step procedure, Call Transaction does both steps online, one after the other. In this method, you call a transaction from your program by

Call transaction <tcode> using <BDCTAB>

Mode <A/N/E>

Update <S/A>

Messages into <MSGTAB>.

Parameter – 1 is transaction code.

Parameter – 2 is name of BDCTAB table.

Parameter – 3 here you are specifying mode in which you execute transaction

A is all screen mode. All the screen of transaction are displayed.

N is no screen mode. No screen is displayed when you execute the transaction.

E is error screen. Only those screens are displayed wherein you have error record.

Parameter – 4 here you are specifying update type by which database table is updated.

S is for Synchronous update in which if you change data of one table then all the related Tables gets updated. And sy-subrc is returned i.e., sy-subrc is returned for once and all.

A is for Asynchronous update. When you change data of one table, the sy-subrc is returned. And then updating of other affected tables takes place. So if system fails to update other tables, still sy-subrc returned is 0 (i.e., when first table gets updated).

Parameter – 5 when you update database table, operation is either successful or unsuccessful or operation is successful with some warning. These messages are stored in internal table, which you specify along with MESSAGE statement. This internal table should be declared like BDCMSGCOLL, a structure available in ABAP/4. It contains the following fields:

1. Tcode: Transaction code

2. Dyname: Batch point module name

3. Dynumb: Batch input Dyn number

4. Msgtyp: Batch input message type (A/E/W/I/S)

5. Msgspra: Batch input Lang, id of message

6. Msgid: Message id

7. MsgvN: Message variables (N = 1 - 4)

For each entry, which is updated in database, table message is available in BDCMSGCOLL. As BDCMSGCOLL is structure, you need to declare a internal table which can contain multiple records (unlike structure).

Steps for CALL TRANSACTION method

1. Internal table for the data (structure similar to your local file)

2. BDCTAB like BDCDATA

3. UPLOAD or WS_UPLOAD function to upload the data from local file to itab. (Considering file is local file)

4. Loop at itab.

Populate BDCTAB table.

Call transaction <tcode> using <BDCTAB>

Mode <A/N/E>

Update <S/A>.

Refresh BDCTAB.

Endloop.

(To populate BDCTAB, You need to transfer each and every field)

The major differences between Session method and Call transaction are as follows:

SESSION METHOD CALL TRANSACTION

1. Data is not updated in database table unless Session is processed. Immediate updation in database table.

2. No sy-subrc is returned. Sy-subrc is returned.

3. Error log is created for error records. Errors need to be handled explicitly

4. Updation in database table is always synchronous Updation in database table can be synchronous Or Asynchronous.

Error Handling in CALL TRANSACTION

When Session Method updates the records in database table, error records are stored in the log file. In Call transaction there is no such log file available and error record is lost unless handled. Usually you need to give report of all the error records i.e., records which are not inserted or updated in the database table. This can be done by the following method:

Steps for the error handling in CALL TRANSACTION

1. Internal table for the data (structure similar to your local file)

2. BDCTAB like BDCDATA

3. Internal table BDCMSG like BDCMSGCOLL

4. Internal table similar to Ist internal table

(Third and fourth steps are for error handling)

5. UPLOAD or WS_UPLOAD function to upload the data from the local file to itab. (Considering file is local file)

6. Loop at itab.

Populate BDCTAB table.

Call transaction <tr.code> using <Bdctab>

Mode <A/N/E>

Update <S/A>

Messages <BDCMSG>.

Perform check.

Refresh BDCTAB.

Endloop.

7 Form check.

IF sy-subrc <> 0. (Call transaction returns the sy-subrc if updating is not successful).

Call function Format_message.

(This function is called to store the message given by system and to display it along with record)

Append itab2.

Display the record and message.

DIRECT INPUT

About Direct Input

In contrast to batch input, this technique does not create sessions, but stores the data directly. It does not simulate the online transaction. 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 be able to activate the restart mechanism, direct input programs must be executed in the background only. Direct input checks the data thoroughly and then updates the database directly.

You can start a Direct Input program in two ways;

Start the program directly

This is the quickest way to see if the program works with your flat file. This option is possible with all direct input programs. If the program ends abnormally, you will not have any logs telling you what has or has not been posted. To minimize the chance of this happening, always use the check file option for the first run with your flat file. This allows you to detect format errors before transfer.

Starting the program via the DI administration transaction

This transaction restarts the processing, if the data transfer program aborts. Since DI document are immediately posted into the SAP D/B, the restart option prevents the duplicate document posting that occurs during a program restart (i.e., without adjusting your flat file).

Direct input is usually done for standard data like material master, FI accounting document, SD sales order and Classification for which SAP has provided standard programs.

First time you work with the Direct Input administration program, you will need to do some preparation before you can transfer data:

- Create variant

- Define job

- Start job

- Restart job

Common batch input errors

- The batch input BDCDATA structure tries to assign values to fields which do not exist in the current transaction screen.

- The screen in the BDCDATA structure does not match the right sequence, or an intermediate screen is missing.

- On exceptional occasions, the logic flow of batch input session does not exactly match that of manual online processing. Testing the sessions online can discover by this.

- The BDCDATA structure contains fields, which are longer than the actual definition.

- Authorization problems.

RECORDING A BATCH INPUT

A B recording allows you to record a R/3 transaction and generate a program that contains all screens and field information in the required BDC-DATA format.

You can either use SHDB transaction for recording or

EDIT&#61614; BATCH INPUT &#61614; SERVICES &#61614;SYSTEM

And from here click recording.

Enter name for the recording.

(Dates are optional)

Click recording.

Enter transaction code.

Enter.

Click Save button.

You finally come to a screen where, you have all the information for each screen including BDC_OKCODE.

• Click Get Transaction.

• Return to BI.

• Click overview.

• Position the cursor on the just recorded entry and click generate program.

• Enter program name.

• Click enter

The program is generated for the particular transaction.

BACKGROUND PROCESSING

Need for Background processing

When a large volume of data is involved, usually all batch inputs are done in background.

The R/3 system includes functions that allow users to work non-interactively or offline. The background processing systems handle these functions.

Non-interactively means that instead of executing the ABAP/4 programs and waiting for an answer, user can submit those programs for execution at a more convenient planned time.

There are several reasons to submit programs for background execution.

• The maximum time allowed for online execution should not exceed 300 seconds. User gets TIMEOUT error and an aborted transaction, if time for execution exceeds 300 seconds. To avoid these types of error, you can submit jobs for background processing.

• You can use the system while your program is executing.

This does not mean that interactive or online work is not useful. Both type of processing have their own purposes. Online work is the most common one entering business data, displaying information, printing small reports, managing the system and so on. Background jobs are mainly used for the following tasks; to process large amount of data, to execute periodic jobs without human intervention, to run program at a more convenient, planned time other than during normal working hours i.e., Nights or weekends.

The transaction for background processing is SM36.

Or

Define jobs&#61614; Jobs &#61614; Administration &#61614;Tools

Or

&#61614;System Jobs&#61614;services

Components of the background jobs

A job in Background processing is a series of steps that can be scheduled and step is a program for background processing.

• Job name. Define the name of assigned to the job. It identifies the job. You can specify up to 32 characters for the name.

• Job class. Indicates the type of background processing priority assigned to the job.

The job class determines the priority of a job. The background system admits three types of job classes: A B & C, which correspond to job priority.

• Job steps. Parameters to be passed for this screen are as follows:

Program name.

Variant if it is report program

Start criteria for the job: Option available for this are as follows:

Immediate - allows you to start a job immediately.

Date/Time - allows you to start a job at a specific name.

After job - you can start a job after a particular job.

After event - allows you to start a job after a particular event.

At operation mode - allows you to start a job when the system switches to a particular operation mode.

Defining Background jobs

It is two step process: Firstly, you define the job and then release it.

When users define a job and save it, they are actually scheduling the report i.e., specifying the job components, the steps, the start time.

When users schedule program for background processing, they are instructing the system to execute an ABAP/4 report or an external program in the background. Scheduled jobs are not executed until they are released. When jobs are released, they are sent for execution to the background processing system at the specified start time. Both scheduling and releasing of jobs require authorizations.

HANDLING OF POP UP SCREEN IN BDC

Many times in transaction pop up screen appears and for this screen you don’t pass any record but some indication to system telling it to proceed further. For example: The following screen

To handle such screen, system has provided a variable called BDC_CURSOR. You pass this variable to BDCDATA and process the screen.

Usually such screen appears in many transactions, in this case you are just passing information, that YES you want to save the information, that means YES should be clicked. So you are transferring this information to BDCDATA i.e., field name of YES which is usually SPOT_OPTION. Instead of BDC_OKCODE, you are passing BDC_CURSOR.

BDC_CURSOR is also used to place cursor on particular field.

[Former Member]

Hi

The early versions of R/3, SAP has been providing batch interfacing techniques. Among these techniques, Batch Data Communication (BDC) is the oldest one. BDC is not bi-directional; it is an integration tool in its typical form. It can only be used for uploading data into RJ3. BDC works through an ABAP program and works on the principle of simulating user input for transactional screen.

The purpose of the Batch Data Communication is to transfer data. The BDC can transfer data from one SAP System to another SAP System or can transfer data from non-SAP System to SAP System too. To transfer data BDC uses normal transaction codes. Two methods are provided to BDC to do this work.

SAP has provided two different types of methods for BDC to do its work. Among these, the first one is called the classical method or session method. Through this method the data can be read by the BDC program from a sequential dataset file. This sequential dataset file is stored in batch-input session. In order to .run the transaction in this session, what one needs is to execute the session. For this, follow these few steps: you can start and subsequently monitor the session firstly from – System à Services à Batch Input or have the session run in the background. In this method to generate the required session, you have to use the function module BDC _ NSERT and BDC _CLOSE.

In the second method the BDC has to use the ABAP statement CALL TRANSACTION USING statement to run a transaction. In the second method, unlike in the first type, you do not need BDC to create a session.

http://www.sapbrainsonline.com/TUTORIALS/TECHNICAL/BDC_tutorial.html