Definitin

[former_member329386]

Hi Experts

Please let me know the Exact technical definition of TRANSACTION and EVENT.

Explain it ?

thanks

[Former Member]

Transaction

To emulate a business transaction, a program may need to perform several steps. A financial program, for example, might transfer funds from a checking account to a savings account with the steps listed in the following pseudocode:

begin transaction

debit checking account

credit savings account

update history log

commit transaction

Either all three of these steps must complete, or none of them at all. Otherwise, data integrity is lost. Because the steps within a transaction are a unified whole, a transaction is often defined as an indivisible unit of work.

A transaction can end in two ways: with a commit or a rollback. When a transaction commits, the data modifications made by its statements are saved. If a statement within a transaction fails, the transaction rolls back, undoing the effects of all statements in the transaction. In the pseudocode, for example, if a disk drive crashed during the credit step, the transaction would roll back and undo the data modifications made by the debit statement. Although the transaction failed, data integrity would be intact because the accounts still balance.

In the preceding pseudocode, the begin and commit statements mark the boundaries of the transaction. When designing an enterprise bean, you determine how the boundaries are set by specifying either container-managed or bean-managed transactions.

https://www.sdn.sap.com/irj/sdn/go/portal/prtroot/docs/library/uuid/d329d190-0201-0010-e7a1-96a9f893...

Events:

Let us take you developed a program then LOAD-OF-PROGRAM and INITIALIZATION these will be fired first when running the program, before the selection screen, if there is one, is fired.

If there is a selection screen, AT SELECTION-SCREEN OUTPUT event will be fired automatically before the screen is shown.

Also, if there is a selection screen, the START-OF-SELECTION event will only be fired when the user clicks the "Execute" button on the selection screen.

TOP-OF-PAGE will automically be fired when you use the first WRITE statement as well as anytime the line count is reached.

http://help.sap.com/saphelp_scm50/helpdata/en/69/b4393c95b04325e10000000a11405a/frameset.htm

Regards.

Edited by: Sravan Prakash.V on Jan 10, 2008 10:38 AM

[Former Member]

transaction: transaction is nothing but a series of dialog screens or simply

we can say that as application.But strictly speaking it is a series of screens

used in a module pool.

Event : Event is nothing but the situational control passing from one block of

code to another block of code.

start-of-selection will trigger automatically.

if you use any other event like initialization it will trigger befor selection

screen display.

means according to situation this will fire.Once the event is trigger then the

code below that will execute.

Regards,

swami