SAP Transactions

1. What is a transaction?
- A transaction is dialog program that modify data objects in a consistent way.

2. What are the necessities of a dialog program must complete?
A dialog program should fulfill the following requirements
- a user friendly user interface.
- Format and consistency checks for the data entered by the user.
- Easy alteration of input errors.
- Access to data by storing it in the data bases.

3. What are the fundamental components of dialog program?
- Screens (Dynpros)
- Each dialog in an SAP system is controlled by dynpros. A dynpros consists of a screen
And its flow logic and controls just one dialog step.
- ABAP/4 module Pool.
Each dynpro refers to exactly one ABAP/4 dialog program .Such a dialog program is also referred as module pool, since it consists of interactive modules.

4. What is PBO and PAI events?
PBO- Process Before Output-It find out the flow logic before displaying the screen.
PAI-Process After Input-It find out the flow logic after the display of the screen and after receiving inputs from the User.

5. What is dynpro? What are its components?
- A dynpro (Dynamic Program) consists of a screen and its flow logic and controls exactly one dialog steps.
- The different components of the dynpro are :
Flow Logic: calls of the ABAP/4 modules for a screen .
Screen layout: Positions of the text, fields, pushbuttons and so on for a screen
Screen feature: Number of the screen, number of the subsequent screen and others
Fields aspects: Definition of the attributes of the individual fields on a screen.

6. What is a ABAP/4 module pool?
-Each dynpro refers to exactly one ABAP/4 dialog program. Such a dialog program is also refer as
a module pool ,since it consists on interactive modules.

7..Can we use WRITE statements in screen fields if no then how is data relocate from field data to screen fields?
-We cannot write field data to the screen using the WRITE statement. The system instead shift data by evaluating screen fields names with ABAP/4 variable names. If both names are the same, it
transfers screen fields values to ABAP/4 programs fields and Vice Versa. This happens instantly after displaying the screen.

8. Can we make use of flow logic control key words in ABAP/4 and vice-versa?
- The flow control of a dynpro consists of a few statements that syntactically reassemble ABAP/4 statements .However ,We cannot use flow control keywords in ABAP/4 and vice-versa.

9. What is GUI standing? How to create /Edit GUI status?
-A GUI status is a subset of the interface elements used for a definite screen. The status comprises those elements that are at present needed by the transaction .The GUI status for a transaction may be composed of the following elements:
-Title bar.
-Mneu bar.
-Application tool bar
-Push buttons.

To generate and edit GUI status and GUI title, we use the Menu Painter.

10. How does the interface between the Dynpro and the ABAP/4 Modules takes place?
-A transaction is a set of screens and ABAP/4 routines, controlled and carry out by a Dialog processor. The Dilaog processor processes screen after the screen, thus triggering the proper ABAP/4 processing of each screen .For each screen, the system process the flow logic that contains the equivalent ABAP/4 processing. The controls passes from screen flow logic to ABAP/4 code and back.

11. How does the Dialog handle user requests?
- when an act is carried out ,the system triggers the PROCESS AFTER INPUT event. The data passed includes field screen data filled by the user and a function code. A function code is a technical name that has been allocated in a screen Painter or Menu Painter to a menu entry, a push button, the ENTER key or a function Key of a screen. An internal work field(ok-code)in the PAI module weigh up the function code, and the suitable action is taken.


12. What is to be defined for a push button fields in the screen attributes?
- A function code has to be defined in the screen attributes for the push buttons in a screen.

13. How the function code is handles in Flow Logic?
- When the User selects a function in a transaction, the system duplicate the function code into a specifically designated work field called OK_CODE. This field is Global in ABAP/4 Module Pool. The OK_CODE can then be calculated in the corresponding PAI module. The function code is always passed in exactly the same way, regardless of whether it comes from a screen’s pushbutton, a menu
option, function key or other GUI element.

14. What controls the screen flow?
- The SET SCREEN and LEAVE SCREEN statements controls screen flow.



15. The Function code at presently active is determined by what Variable?
- The function code presently active in a Program can be determined from the SY-UCOMM Variable.


16. What are the “field” and “chain” Statements?
- The FIELD and CHAIN flow logic declaration let you Program Your own checks. FIELD and CHAIN tell the system which fields you are checking and Whether the System should carry out Checks in the flow logic or call an ABAP/4 Module.

17. What is an “on input filed” statements?
- ON INPUT
The ABAP/4 module is called only if a field have the Value other than the initial Value. This first Value is determined by the field’s Data Type: blanks for character Fields, Zeroes for numeric. If the user modify the Fields Value back t o its initial value, ON INPUT does not trigger a call.


18. What is an “on request Field” statement?
- ON REQUEST
The ABAP/4 Module is called only if the client has entered the value in the field value since the last screen display .The Value counts as changed Even if the User simply types in the value that was previously there .In common ,the ON REQUEST condition is triggered through any
Form of” MANUAL INPUT’.

19. What is an on”*-input filed” statement?
ON *-INPUT
- The ABAP/4 module is called if the user has entered the “*” in the first character of the field, and the field has the feature *-entry in the screen Painter.You can use this option in Exceptionla cases where you want to check only fields with certain Kinds of Input.


20. What is conditional chain statement?
ON CHAIN-INPUT similar to ON INPUT.
The ABAP/4 module is called if any one of the fields in the chain contains a value other than its initial value (blank or nulls).
ON CHAIN-REQUEST
This state functions just like ON REQUEST, but the ABAP/4 module is called if any one of the fields in the chain changes value.

21. What is “at exit-command:?
The flowlogic Keyword at EXIT-COMMAND is a particular addition to the MODULE statement in the Flow Logic .AT EXIT-COMMAND lets you call a module ahead of the system executes the automatic fields checks.

22. Which Function type has to be used for using “at exit-command” ?
- To Use AT EXIT – COMMAND, We must allocate a function Type “E” to the applicable function in the MENU Painter OR Screen Painter.

23. What are the different message types available in the ABAP/4 ?
- There are 5 types of message types available.
- E: ERROR
- W-WARNING
- I –INFORMATION
- A-ABNORMAL TERMINATION.
- S-SUCCESS

Of the two “ next screen “ attributes the attributes that has more priority is -------------------.
Dynamic.


Navigation to a subsequent screen can be specified statically/dynamically .(TRUE/FALSE).
TRUE.


Dynamic screen chain for a screen can be set using ------------- and ----------------- commands

Set Screen, Call screen.

27. The commands through Which an ABAP/4 Module can “branch to “ or “call” the next screen are

1.------------,2--------------,3---------------,4------------.

- Set screen,Call screen ,Leave screen, Leave to screen .


28. What is difference between SET SCREEN and CALL SCREEN ?

- With SET SCREEN the present screen only spell out the next screen in the chain , control branches to this next screen as soon as the present screen has been processed .Return from next screen to present screen is not automatic .It does not interrupt processing of the current screen. If we want to branch to the next screen without finishing the current one ,use LEAVE SCREEN.

- With CALL SCREEN , the existing (calling) chain is suspended , and a next screen (screen chain) is called .The called can then return to the suspended chain with the statement LEAVE SCREEN TO SCREEN 0 .Sometime we might want to let an user call a pop up screen from the main application screen to let him enter secondary information. After they have completed their entries, the users should be able to close the popup and return directly to the place where they left off in the main screen. Here comes CALL SCREEN into picture .This statement lets us insert such a sequence into the current one.