Call Transaction MethodDescribe the Call Transaction Method for Batch Input.
Differentiate the different batch input methods.
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SAPMF02K 0106 X
BDC_OKCODE =UPDA
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In a batch input program, the contents of the BDC table can be used three ways to perform the data transfer to the SAP system:
Use the BDC table to create a batch input session.
In this case, the batch input program is often called a BDC program.
Use the BDC table in a “CALL TRANSACTION USING” statement.
Use the BDC table in a “CALL DIALOG” statement (outdated).
In chapter 5, we covered the first method – creating a batch input session with the contents of the BDC table.
In this chapter, we will cover the batch input method – using the BDC table in the “CALL TRANSACTION USING”.
When you perform batch input, you will generally be deciding between the first two methods – creating a batch input session or using the “CALL TRANSACTION USING” statement.
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How are errors handled?
Create batch
input session
(BDC Program):
During the processing of the batch input session
Automatically by the system during the processing of the batch input session
CALL TRANSACTION:
CALL DIALOG:
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Two questions illustrate the main differences between creating a batch input session and using the “CALL TRANSACTION/DIALOG”:
When is the SAP database updated?
How are errors handled?
When is the SAP database updated?
If you create a batch input session in a BDC program, the SAP database is updated during the processing of the batch input session, not the execution of the BDC program.
If you use the “CALL TRANSACTION” or “CALL DIALOG” statement, the SAP database is updated during the execution of the batch input program. In other words, the timing issue we covered in the previous chapter is not an issue with these two alternatives because the database is updated during the execution of the batch input program.
How are errors handled?
If you create a batch input session in a BDC program, errors are handled automatically by the system during the processing of the batch input session. Errors are recorded in a log and with the batch input session error is kept.
If you use the “CALL TRANSACTION” or “CALL DIALOG” statement, errors are not handled automatically by the system. Errors must be handled in the batch input program.
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City
Boston
To illustrate the “CALL TRANSACTION” and “CALL DIALOG” methods, we will use the example to change vendors coming from a sequential file.
Example - Change Vendors
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To illustrate the “CALL TRANSACTION” and “CALL DIALOG” methods, we will use the example to change vendors coming from a sequential file on the application server.
In chapter 5, we used this example to create a batch input session. In this chapter, we will first use this example with the “CALL TRANSACTION” method. Then, we will use it with the “CALL DIALOG” method.
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“CALL TRANSACTION USING” Statement
<update mode>
S: synchronous
A: asynchronous
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The “CALL TRANSACTION” statement executes an online program. When this transaction is completed, processing returns to the “calling” program. To perform batch input with the “CALL TRANSACTION” statement, the “USING” addition is required to send the contents of the BDC table to the transaction:
CALL TRANSACTION <transaction code>
The <bdc table> must be declared “LIKE BDCDATA”.
The only required addition for batch input is “USING”. The other additions are only valid in conjunction with the “USING” addition.
The <display mode> determines how the transaction will be processed: ‘A’ (display all), ‘E’ (display errors only), or ‘N’ (no display). The default is ‘A’.
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<display mode>
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The <update mode> determines how database update will occur: ‘S’ (synchronous) or ‘A’ (asynchronous) or L (local update). The default is ‘A’.
Synchronous updating indicates that an update is completed for the transaction before processing returns to the “calling” program.
Asynchronous updating indicates that processing returns to the “calling” program immediately after the transaction is completed, even before the update is completed.
Local update indicates that updates of the called program are executed in such a way as if the SET UPDATE TASK LOCAL statement had been executed in it.
System messages issued during the transaction can be stored in the <msg int. table>. This internal table must be declared “LIKE BDCMSGCOLL”.
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DATA: BDC_TAB TYPE STANDARD TABLE OF BDCDATA INITIAL SIZE 6,
WA_BDC_TAB TYPE BDCDATA.
INFILE(20) VALUE ‘./bc180_file4’.
Step #1
Step #2
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To perform batch input using the “CALL TRANSACTION USING” statement with multiple records from a sequential file on the application server, perform the following steps in a batch input program:
Step #1: Create the BDC table.
This internal table must be declared “TYPE BDCDATA”.
Step #2: Define the structure in which the file’s records will be read.
This structure should match the structure of the
file’s records.
The sequential file we are reading has the same format as the one from chapter 5 (see page 12 of chapter 5). It is structured in lines, so we will open it “IN TEXT MODE”.
These steps are continued on the next page.
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DO.
IF SY-SUBRC <> 0.
Step #3
Step #4
Step #5
Step #6
Step #7
Step #8
Step #9
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Steps to perform batch input using the “CALL TRANSACTION USING” statement (continued from previous page):
Step #3: Open the file “FOR INPUT”.
Step #4: Read a record from the file into the structure.
To read the complete file, you must code the “READ DATASET” statement in a DO loop.
Step #5: Code a way out (EXIT) of the DO loop.
If SY-SUBRC is not 0, the end of the file has already been reached.
Step #6: Fill the BDC table with the appropriate data for the transaction (see next page).
This step will be executed for each record in the sequential file.
Step #7: Insert a transaction’s data (from the BDC table) into the transaction directly by using the “CALL TRANSACTION USING” statement.
This step will be executed for each record in the sequential file.
The display mode determines how this transaction is processed
(i.e., will you see the transaction’s screens or not).
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DO.
IF SY-SUBRC <> 0.
** This program is continued on the next slide **
Step #3
Step #4
Step #5
Step #6
Step #7
Step #8
Step #9
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Step #8: Check SY-SUBRC to determine if an error occurred during the transaction (SY-SUBRC <> 0).
The system does not automatically handle these errors like it does during the processing of a batch input session. You must handle these errors in the program (see page 8).
Step #9: Close the file.
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Example #1 - Subroutines
Notice that the vendor number and street values are coming from the file’s records read into the “INREC” structure.
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The two subroutines above are used to fill the BDC table. These two subroutines are executed just before the BDC table’s contents are passed to the transaction with the “CALL TRANSACTION USING” statement.
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Create a batch input session with the record(s) in error.
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With the “CALL TRANSACTION USING” statement (and the “CALL DIALOG” statement), errors are not handled automatically by the system. Therefore, you must handle these errors in the batch input program.
After a “CALL TRANSACTION USING” statement (or a “CALL DIALOG” statement), the value of SY-SUBRC indicates the success or failure
of the transaction:
If SY-SUBRC is zero, the transaction (or dialog module) was successful.
If SY-SUBRC is not zero, the transaction (or dialog module) was
not successful.
Write an error report.
Create a batch input session with the record(s) in error.
This list of error handling methods is not complete. The exact method chosen will depend on your specific requirements. Also, these methods can be combined (i.e., you can create an error report and send the records in error to an error file).
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Synchronous versus Asynchronous
With synchronous updating, we can check SY-SUBRC to determine the success of the transaction and the actual update to the database.
With asynchronous updating, we can check SY-SUBRC to determine the success of the transaction only, not the actual update to the database.
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In the “CALL TRANSACTION USING” statement, you can specify the update mode as synchronous or asynchronous. To restate the difference:
Synchronous updating indicates that an update is completed for the transaction before processing returns to the “calling” program.
Asynchronous updating indicates that processing returns to the “calling” program immediately after the transaction is completed, even before the update is completed.
The difference in these update modes creates a trade-off between the execution speed and the meaning of the return code.
With respect to the execution speed:
Synchronous updating is slower than asynchronous updating because processing does not return to the “calling” program until the update is complete.
Remember that the update mode when processing batch input sessions is always synchronous.
With respect to the meaning of the return code:
The return code (SY-SUBRC) after synchronous updating indicates the success or failure of the actual update. The return code after asynchronous updating only indicates the success or failure of the transaction, not the update.
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Demonstration
Creation of a custom BDC program and changing customer address with transaction XD02 (Change Customer) using the Call transaction method.
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Practice
Creation of a custom BDC program and changing customer address with transaction XD02 (Change Customer) using the Call transaction method.
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Summary
If you use the “CALL TRANSACTION” or “CALL DIALOG” statement, errors are not handled automatically by the system. Errors must be handled in the batch input program.
The “CALL TRANSACTION” statement executes an online program. When this transaction is completed, processing returns to the “calling” program.
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Questions
What are the different batch input methods present in SAP for data upload?
What is the difference between synchronous and asynchronous update?
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