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ABAP 정의 및 FAQ(영문)

sapjoy 2008.05.26 21:14 조회 수 : 5751 추천:1


What is an ABAP?
ABAP (Advanced Business Application Programming) is a high level programming language created by the German software company SAP. It is currently positioned as the language for programming SAP's Web Application Server, part of its Net Weaver platform for building business applications. Its syntax is somewhat similar to COBOL.



1. What is an ABAP data dictionary?
ABAP 4 data dictionary describes the logical structures of the objects used in application development and shows how they are mapped to the underlying relational database in tables/views.



2. What are domains and data element?
Domains: Domain is the central object for describing the technical characteristics of an attribute of an business objects. It describes the value range of the field. Data Element: It is used to describe the semantic definition of the table fields like description the field. Data element describes how a field can be displayed to end-user.



3. What is foreign key relationship?
A relationship which can be defined between tables and must be explicitly defined at field level. Foreign keys are used to ensure the consistency of data. Data entered should be checked against existing data to ensure that there are now contradiction. While defining foreign key relationship cardinality has to be specified. Cardinality mentions how many dependent records or how referenced records are possible.



4. Describe data classes.
Master data: It is the data which is seldomly changed. Transaction data: It is the data which is often changed. Organization data: It is a customizing data which is entered in the system when the system is configured and is then rarely changed. System data: It is the data which R/3 system needs for itself.



5. What are indexes?
Indexes are described as a copy of a database table reduced to specific fields. This data exists in sorted form. This sorting form ease fast access to the field of the tables. In order that other fields are also read, a pointer to the associated record of the actual table are included in the index. Yhe indexes are activated along with the table and are created automatically with it in the database.



6. Difference between transparent tables and pooled tables.
Transparent tables: Transparent tables in the dictionary has a one-to-one relation with the table in database. Its structure corresponds to single database field. Table in the database has the same name as in the dictionary. Transparent table holds application data. Pooled tables. Pooled tables in the dictionary has a many-to-one relation with the table in database. Table in the database has the different name as in the dictionary. Pooled table are stored in table pool at the database level.



7. What is an ABAP/4 Query?
ABAP/4 Query is a powerful tool to generate simple reports without any coding. ABAP/4 Query can generate the following 3 simple reports: Basic List: It is the simple reports. Statistics: Reports with statistical functions like Average, Percentages. Ranked Lists: For analytical reports. - For creating a ABAP/4 Query, programmer has to create user group and a functional group. Functional group can be created using with or without logical database table. Finally, assign user group to functional group. Finally, create a query on the functional group generated.



8. What is BDC programming?
Transferring of large/external/legacy data into SAP system using Batch Input programming. Batch input is a automatic procedure referred to as BDC(Batch Data Communications).The central component of the transfer is a queue file which receives the data vie a batch input programs and groups associated data into “sessions”.



9. What are the functional modules used in sequence in BDC?
These are the 3 functional modules which are used in a sequence to perform a data transfer successfully using BDC programming: BDC_OPEN_GROUP - Parameters like Name of the client, sessions and user name are specified in this functional modules. BDC_INSERT - It is used to insert the data for one transaction into a session. BDC_CLOSE_GROUP - This is used to close the batch input session.



10. What are internal tables?
Internal tables are a standard data type object which exists only during the runtime of the program. They are used to perform table calculations on subsets of database tables and for re-organising the contents of database tables according to users need.
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11. What is ITS?
What are the merits of ITS?- ITS is a Internet Transaction Server. ITS forms an interface between HTTP server and R/3 system, which converts screen provided data by the R/3 system into HTML documents and vice-versa. Merits of ITS: A complete web transaction can be developed and tested in R/3 system. All transaction components, including those used by the ITS outside the R/3 system at runtime, can be stored in the R/3 system. The advantage of automatic language processing in the R/3 system can be utilized to language-dependent HTML documents at runtime.



12. What is DynPro?
DynPro is a Dynamic Programming which is a combination of screen and the associated flow logic Screen is also called as DynPro.



13. What are screen painter and menu painter?
Screen painter: Screen painter is a tool to design and maintain screen and its elements. It allows user to create GUI screens for the transactions. Attributes, layout, filed attributes and flow logic are the elements of Screen painter. Menu painter: Menu painter is a tool to design the interface components. Status, menu bars, menu lists, F-key settings, functions and titles are the components of Menu painters. Screen painter and menu painter both are the graphical interface of an ABAP/4 applications.



14. What are the components of SAP scripts?
SAP scripts is a word processing tool of SAP which has the following components: Standard text. It is like a standard normal documents. Layout sets. - Layout set consists of the following components: Windows and pages, Paragraph formats, Character formats. Creating forms in the R/3 system. Every layout set consists of Header, paragraph, and character string. ABAP/4 program.



15. What is ALV programming in ABAP? When is this grid used in ABAP?
ALV is Application List viewer. Sap provides a set of ALV (ABAP LIST VIEWER) function modules which can be put into use to embellish the output of a report. This set of ALV functions is used to enhance the readability and functionality of any report output. Cases arise in sap when the output of a report contains columns extending more than 255 characters in length. In such cases, this set of ALV functions can help choose selected columns and arrange the different columns from a report output and also save different variants for report display. This is a very efficient tool for dynamically sorting and arranging the columns from a report output. The report output can contain up to 90 columns in the display with the wide array of display options.



16. What are the events in ABAP/4 language?
Initialization, At selection-screen, Start-of-selection, end-of-selection, top-of-page, end-of-page, At line-selection, At user-command, At PF, Get, At New, At LAST, AT END, AT FIRST.



17. What is CTS and what do you know about it?
The Change and Transport System (CTS) is a tool that helps you to organize development projects in the ABAP Workbench and in Customizing, and then transport the changes between the SAP Systems and clients in your system landscape. This documentation provides you with an overview of how to manage changes with the CTS and essential information on setting up your system and client landscape and deciding on a transport strategy. Read and follow this documentation when planning your development project.



18. What are logical databases? What are the advantages/ dis-advantages of logical databases?
To read data from a database tables we use logical database. A logical database provides read-only access to a group of related tables to an ABAP/4 program. Advantages: i)check functions which check that user input is complete, correct,and plausible. ii)Meaningful data selection. iii)central authorization checks for database accesses. iv)good read access performance while retaining the hierarchical data view determined by the application logic. dis advantages: i)If you donot specify a logical database in the program attributes,the GET events never occur. ii)There is no ENDGET command,so the code block associated with an event ends with the next event statement (such as another GET or an END-OF-SELECTION).



19. What is a batch input session?
BATCH INPUT SESSION is an intermediate step between internal table and database table. Data along with the action is stored in session ie data for screen fields, to which screen it is passed, program name behind it, and how next screen is processed.



20. How to upload data using CATT ?
These are the steps to be followed to Upload data through CATT: Creation of the CATT test case & recording the sample data input. Download of the source file template. Modification of the source file. Upload of the data from the source file.
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21. What is Smart Forms?
Smart Forms allows you to create forms using a graphical design tool with robust functionality, color, and more. Additionally, all new forms developed at SAP will be created with the new Smart Form solution.



22. How can I make a differentiation between dependent and independent data?
Client dependent or independent transfer requirements include client specific or cross client objects in the change requests. Workbench objects like SAPscripts are client specific, some entries in customizing are client independent. If you display the object list for one change request, and then for each object the object attributes, you will find the flag client specific. If one object in the task list has this flag on, then that transport will be client dependent.



23. What is the difference between macro and subroutine?
Macros can only be used in the program the are defined in and only after the definition are expanded at compilation / generation. Subroutines (FORM) can be called from both the program the are defined in and other programs . A MACRO is more or less an abbreviation for some lines of code that are used more than once or twice. A FORM is a local subroutine (which can be called external). A FUNCTION is (more or less) a subroutine that is called external. Since debugging a MACRO is not really possible, prevent the use of them (I’ve never used them, but seen them in action). If the subroutine is used only local (called internal) use a FORM. If the subroutine is called external (used by more than one program) use a FUNCTION.



What is the differrences between structure and table in data dictionary in ABAP?
Structure and table both are 2/2 matrices but there are many differences between table and structure.
1. Table can store the data physically but a structure dose not store.
2. Table can have primary key but a structure dose not have.
3. Table can have the technical attribute but a structure dose not have.
structure does't contain technical attributes.
structure does't contain primary key.
structure does't stores underline database level.
What is the difference between collect and sum?
SUM.
When processing an internal table in a block starting with LOOP and concluded by ENDLOOP , SUM calculates the control totals of all fields of type I , F and P (see also ABAP/4 number types ) and places them in the LOOP output area (header line of the internal table or an explicitly specified work area).
When you use SUM in a LOOP with an explicitly specified output area, this output area must be compatible with the line type of the internal table.When using LOOP to process a sorted extract (see SORT ), the control total of f at the end of the group appears in the field SUM(f) - - if f is type I , F or P .
COLLECT.
COLLECT is used to create unique or compressed datsets. The key fields are the default key fields of the internal table itab .
If you use only COLLECT to fill an internal table, COLLECT makes sure that the internal table does not contain two entries with the same default key fields.
If, besides its default key fields, the internal table contains number fields,the contents of these number fields are added together if the internal table already contains an entry with the same key fields.
If the default key of an internal table processed with COLLECT is blank, all the values are added up in the first table line.
If you specify wa INTO , the entry to be processed is taken from the explicitly specified work area wa . If not, it comes from the header line of the internal table itab .
After COLLECT , the system field SY-TABIX contains the index of the - existing or new - table entry with default key fields which match those of the entry to be processed.
COLLECT can create unique or compressed datasets and should be used precisely for this purpose. If uniqueness or compression are unimportant, or two values with identical default key field values could not possibly occur in your particular task, you should use APPEND instead. However, for a unique or compressed dataset which is also efficient, COLLECT is the statement to use.
If you process a table with COLLECT , you should also use COLLECT to fill it. Only by doing this can you guarantee that the internal table will actually be unique or compressed, as described above and COLLECT will run very efficiently.
If you use COLLECT with an explicitly specified work area, it must be compatible with the line type of the internal table.



How we format the data beofore before write statment in report ?
We can format the reports output by using the loop events like:
1.at first
2.at new
3.at last
etc check docu



What is the difference between Table and Template?
table is a dynamic and template is a static



When do we use End-of-selection?
End-of-selection event are mostly used when we are writing HR-ABAP code. In the HR-ABAP code, data is retrived in the Start-of-selection event and Printing on the list and all will be done in End-of-selection event.



In evevts start-of-selection is default event. When we have to use this event explicitly? Why?
The default event in the ABAP is Start-of-selection.We have to call explicitely this event when you are writing other than ths event , that is when you write AT SELECTION-SCREEN EVENTS OR INITIALIZATION EVENT etc,you have to explicitely mention the Start-of-selection event while you are writing the logic.
Before these events called ,all the code you have written come into this default Start-of-selection screen event.



What is the differences between ABAP and OOABAP. In which situation we use OOABAP?
OOABAP is used to develop BSP/PCUI applications and also anthing involved object oriented like BADIs, SmartForms..etc.where as ABAP is used to develop traditional programs in R/3.



What is table buffer? Which type of tables used this buffer?
buffer is nothing but a memory area. table is buffered means that table information is available on application server. when you call data from database table it will come from application server.
transperent and pooled tables are buffered. cluster tables can not buffered.
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What is the use of pretty printer ?
Exactly where can we link the functional module to abap coding.
Pretty Printer is used to format the ABAP Code we write in ABAP Editor ,like KEY WORDS in Capitals and remaining are in small letters which is also depend on system settings.
We can call the function module in the ABAP Code .Press the Pattern button on Appl. tool bar then u will get box where u write the function module NAME which u want to call in the code by selecting the radio button CALL FUNCTION. In this way we link function module to ABAP Code.



What is the difference between SAP memory and ABAP memory?
Answer1:
data sending between main sessions using get parameter and set parameter is sap memory
data sending between internal sessions using import or export parameters is abap memory
Answer2:
sap memory is a global memory whereas abap memory is local memory.
For example, we have four programs in abap memory and assigned some varibles to a particular program in abap memory then those varibles can't be used by anyother program in abap memory i.e., the variables are only for that program and also local to that memory,whereas sap memory can access all the abap memory or else it can perform any kind of modifications.
Answer3:
SAP memory is available to the user during the entire terminal session.
ABAP memory is available to the user during life time of external session.



What is the difference between Type and Like?
Answer1:
TYPE, you assign datatype directly to the data object while declaring.
LIKE,you assign the datatype of another object to the declaring data object. The datatype is referenced indirectly.
Answer2:
Type is a keyword used to refer to a data type whereas Like is a keyword used to copy the existing properties of already existing data object.
Answer3:
type refers the existing data type
like refers the existing data object



What is Tcode SE16. For what is it used. Explain briefly?
Answer1:
SE16 is a T-code for object browser.
Generally used to search the fields of SAP Tables . and respective data.
Answer2:
se16 is a data browse and it is used to view the contents of the table and we cannot change or append new fields to the existing structure of the table as we cannot view the structure level display using the se16



What are different ABAP/4 editors? What are the differences?
The 2 editors are se38 and se80 both have the abap editor in place. In se38 you can go create programs and view online reports and basically do all thedevelopmet of objects in this editor. In se80 ( object navigator) there are additional features such as creating packages,module pool , function group ,classes, programs ( where you can create ur programs) and BSP applications .
What is difference between dialog program and a report?
Report is a excecutable program
Dialog is a module pool program.It has to be executed via a transaction only.
Dialog programming is used for customization ofscreens
How do you connect to the remote server if you are working from the office for the client in remote place.
WAS web application server or ITS are generally used for this purpose. If you are sitting at your office with a server which is in the system and the other server is at the clients place you can generate IDOC, intermidiate documents which carry the data you want to transfer or the documents you want to transfer, these IDOC are interpretted by the system at the recieving end with the message class with which it is bound with. If you want to logon a system which is very distant..then remote login can be used this depends on the internet speed.



Explain about roll area , Dispatcher, ABAP-Processor.
Answer1:
Roll area is nothing but memory allocated by work process. It holds the information needed by R/3 about programs execution such as value of the variables.
Dispatcher :All the requests that come from presentation server will be directed first to dispatcher. Further dispatcher sends this requests to work process on FIFO(First In and First Out) basis.
Answer2:
Dispatcher recieves the request from client and assigns the request to one of the work process.
Roll area: Each workprocess works in a particular memory that memory is known as Role Area, which consists of User context and session data.
ABAP- Processor :is an interpretor which can execute logic



Which one is not an exit comand ? (Exit, cancle, stop, back)
STOP.
Effect :The statement STOP is only to be used in executable programs
EXIT.
Effect :If the EXIT statement is executed outside of a loop, it will immediately terminate the current processing block.
BACK.
Effect : This statement positions the list cursor on the first position of the first line in a logical unit.
So "Cancle" is not an exit command



What is Field sysmbol ?
Answer1:
You can use field symbols to make the program more dynamic. In this exanmple the name of a table control is substituted by a field symbol. Thus you cal call the form with any internal table, using the name of the tablæe control as a parameter.
Example
form insert_row
using p_tc_name.
field-symbols <tc> type cxtab_control. "Table control
assign (p_tc_name) to <tc>.




  • insert 100 lines in table control


<tc>-lines = 100.
Answer2:
fieldsymbol has the same concept as pointer in c,
fieldsymbol don't point to a data type like char, num instead of that it points to the memory block. the syntax for fieldsymbol is
FIELD-SYMBOL <N>.
EG. FOR FIELD SYMBOL.
DATA: DAT LIKE SY-DATUM,
TIM LIKE SY-UZEIT,
CHAR(3) TYPE C VALUE 'ADF'.
FIELD-SYMBOL : <FS>.
MOVE DAT TO <FS>.
WRITE:/ <FS>.
MOVE TIM TO <FS>.
WRITE:/ <FS>.
MOVE CHAR TO <FS>.
WRITE:/ <FS>.
The output will be
Today's date
current time
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What is lock object ?
LockObjects used to synchornize access of several users using same data.



Why BAPI need then BDC ?
BAPI"S provide the standard interface to other applications apart from SAP and within differnt vesions of SAP too. Also it is OOD bases so dosen"t depends on screen flow. BDC gets failed if we make changes for screen changes through IMG customization



What are the advantages and disadvantages of using views in ABAP porgramming ?
dvantages: view is used to retrieve the data very fastly from the database tables
*memory wastage is reduced
*faster than joins to retrieve the data from database tables
disadvantages:
view is not a container,it will not hold the data
*view memory is not permanent memory



How data is stored in cluster table?
A cluster table conatins data from mulitple DDIC tables.
It stores data as a name value pair ( varkey, vardata)



Have you used performance tuning? What major steps will you use for these?
First of all tunning can be done
In three ways: disk i/o ,sql tunning , memory tunning,
Before tunning u have to get the status of your database using
Oracle utility called statpack , tkprof, then you should go for tunning



How to create client independent tables?
client independent tables:
the table in which the first field is not mandt is the client independent tables
*mandt is the field with mandt as the data element
*automatically client which we login is populated to mandt
What type of user exits have you written?
there are four types
1.function exit
2.menu ixit
3.screen exit.
4.field exit.
these are the user exits



How can you debugg a script form?
SE71 -> give the form name -> utilities -> activate debugger



How do we debug sapscript?
First we need to put Break point in Print program where ever you want to stop the execution.
After in SE71 give your form name and go to Utilities-->Active De-bugger.
Then go to your transcation like VF03(for Invoice or Credit memo) etc to see the print preview or print the form execute it.
When you execute it the the form Debugging will get activated and you can see your Form execution step by step.



What are the different types of data dictionary objects?
Answer1
Data Dictionary Objects




  • Tables
  • Views
  • Domain
  • Data Element
  • Type Groups
  • Search Helps/Matchcode Objects
  • Lock objects
  • Structures
  • Table Types


Answer2
the dictionary objects are:
domain
dataelements
tables
views
structures
typegroups
search helps
lock objects etc which are data base related objects in sap



What is the step by step process to create a table in data dictionary?
Answer1
steps to create database tables
1.go to se11
2.give name the database table
3.give short description for the table
4.Give delivery class name as A and data browser / table view maint as Display/maintenence allowed
5.select fields tab
6.give field name data type(user defined element type/built-in-type),short text
7.select technical settings tab ,give data class as appl0 and size category as 0
8.save it
9.go utillities menu click table contents select create and enter the field values then select display in table contents and u can view the table values with field lables
Answer2
bottom to top approach:
_________________________
step 1:
creating a domain:
*se11,select the object type as domain ,name it ,create,description,enter the datatype and length(size),save ,activate
step2:
creating a dataelement;
se11,select the object type as :date element,name it ,create,desc,assign it with a domain what we created now,save,activate it.
step3:
creating a table;
se11,select the object type as table,name it, create,
enter the field name and assign it with the data element instead of assigning a datatype to it,
like this create req fields:
on behalf of this:
table maintainence:
assign the type of the table ie.,A C G L S
NEXT
maintaince:
allowed,not allowed ,allowed with restricions
______________________________________________
fields of a table:(as descripted above)
___________________________________________
techical settings:
A0
OR
A1
AND
BUFFERED OR NON-BUFFERED



Can a transparent table exist in data dictionary but not in the data base physically?
Answer1
NO. TRANSPARENT TABLE DO EXIST WITH THE SAME STRUCTURE BOTH IN THE DICTIONARY AS WELL AS IN THE DATABASE,EXACTLY WITH THE SAME DATA AND FIELDS.
No,
at the point you will activate your table a same transparent table is going to be create in database
Answer2
Yes, a transparent table(definition) can exist in the data dictionary and not in the database. In this case, it is not activated
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What are the domains and data elements?
domains:
___________
domains are the dictionary objects that are assigned with constants and data types
data elements:
______________
data elements are dictionary objects that are assigned with the domains.
uses:'




  • data elements are used to create relation between tables.
  • data elements are used to transfer the data from one R/3 to another R/3.
  • to create search helps.


What is a collect statement? How is it different from append?
APPEND :
IT IS USED TO GET THE RECORD FROM THE INTERNAL TABLE HEADER TO THE BODY AREA
IT ALLOWS DUPLICATION
COLLECT:
IT IS USED TO A GET A RECORD FROM HEADER TO THE BODY AREA BUT IT WILL NOT ALLOW ANY DUPLICATION EXCEPT IF THERE IS ANY NUMERIC FIELS IT ADDS THAT FIELDS DATA BUT NOT AS A NEW RECORD
On ABAP: Did you set up a workflow? Are you familiar with all steps for setting up a workflow?
Yes.
Execute the Txn SWDD(Creating a new Workflow).
In the header of the Workflow, define the Business Object and Event you refer to for triggering the Wf.
Create the Steps required for your workflow(Activity).
Inside the Activity, Create the task and assign the Business Object and the related method for that business object.
Activate the Workflow.


 



In the ‘select’ statement what is “group by”?
Group by clause is used to fetch the data from the table by the specified field
ex.select count (*) from emptable group by deptno where deptno = 1.
It is used to find the number of employees present in the specified department no.