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SAP TERMINOLOGY

Master data is a collection of information about a person or an object, e.g. a cost object, vendor, or G/L account. For example, a vendor master record contains not only general information such as the vendor's name and address, but also specific information, such as payment terms and delivery instructions. Generally for end users, master data is reference data that you will look up and use, but not create or change.

Transactional data is data related to a single business event such as a purchase requisition or a request for payment. When you create a requisition, for example, SAP creates an electronic document for that particular transaction. SAP gives the transaction a document number and adds the document to the transaction data that is already in the system. Whenever you complete a transaction in SAP, that is, when you create, change, or print a document in SAP, this document number appears at the bottom of the screen.

Workflow A routing tool in SAP that forwards documents for review or approval. For example, a requisition that needs to be approved is sent to the appropriate approver's inbox.Workflow is also used to route journal vouchers, credit card charges, and other documents in SAP.

Cost Object: A Cost Object collects expenses and revenues for a particular purpose, such as a research project. In SAP there are three types of cost objects: Cost Center, Internal Order, and WBS (Work Breakdown Structure) Element (see below for definition).

Cost Center: General or operating Cost Objects are known in SAP as Cost Centers. Cost Centers are budgeted on the fiscal year.

Internal Order: A non-sponsored Cost Object (for example, funding from the MIT Provost) used to track costs over periods other than fiscal years. Internal Orders are often created to track gifts or endowments at MIT.

WBS Element: WBS Elements are funded by outside sponsors and are used to track costs of a particular research project over the entire span of its activity. They may also be created to track other sponsored activities, such as gifts.

G/L Account: G/L accounts are also called Cost Elements in SAP. They are a classification by expense or revenue type. In the CO (Controlling) module of SAP, the term Cost Element is used. In the FI(Financial) module, the term G/L Account is used. These terms are used interchangeably for reporting, requisitions, and journal vouchers.

Database tables and open SQL Add a single record to a database table insert into values Inserting all lines from an internal table into a database table: insert from table Delete all records Select * from zmellemtab. delete zmellemtab. endselect. Deleting records using records from an internal table delete employees from table itab.

Q & A BASIS LAYER

What are the central interfaces of the R/3 system ?
Presentation interface
Database interface
Operating system interface

Which interface controls what is shown on the p.c. ?
Presentation interface

Which interface converts SQL requirements in the SAP development system to those of the database ?
Database interface

What is SAP dispatcher ?
SAP dispatcher is the control agent which manages the resources for the R/3 applications.

What are the functions of dispatcher ?
Equal distribution of transaction load to the work processes
Management of buffer areas in main memory Integration of the presentation levels
Organization of communication activies

What is a work process ?
A work process is where individual dialog steps are actually processed and the work is done. Each work process handles one type of request.

Name various work processes of R/3 system ?
1) Dialog or Online ( processes only one request at a time )
2) Background ( started at a specified time ) 3) Update ( primary or secondary ) 4) Enque( lock mechanism ) 5) Spool ( generated online or during back ground processing For printing )

What are the types of Update requests ?
An update request can be divided into one primary (V1) and several Secondary update components (V2). Time-critical operations are placed in V1 component and those whose timing are less critical are placed in V2 components. If a V1 update fails, V2 components will not be processed.

What are the roll and page areas ?
- Roll and page areas are SAP R/3 buffers used to store user contexts (process requests) . The SAP dispatcher assigns process requests to work processes as they are received. If the work process is unavailable the process requests are queued in the roll and page areas. Paging area holds data from the application programs. Roll area holds data from previous dialog steps and data that characterizes user.

What is a Spool request ?
Spool requests are generated during dialog or background processing and placed in the spool database with information about the printer and print format. The actual data is placed in the Tem Se (Temporary Sequential objects).

What are the different database integrities ?
- Semantic integrity
- Relational integrity
- Primary key integrity
- Value set integrity
- Foreign key integrity and
- Operational integrity.

DATA DICTIONARY

Type of a table or structure
The table type determines how the logical table description defined in the ABAP/4 Dictionary is reproduced on the database. There are the following table types:

1. transparent table
2. structure
3. append structure

For internal purposes, such as storing control data or update texts, there are in addition the following table types:

1. pooled table
2. cluster table
3. generated view structure

Transparent table There is a physical table on the database for each transparent table. The names of the physical tables and the logical table definition in the ABAP/4 Dictionary correspond. All business data and application data are stored in transparent tables.

Structure No data records exist in the database for a structure. Structures are used for the interface definition between programs or between screens and programs.

Append structure An append structure defines a set of fields which belong to another table or structure but which are treated in the correction administration as its own object. Append structures are used to support modifications.

Pooled table Pooled tables can be used to store control data (e.g. screen sequences, program parameters or temporary data). Several pooled tables can be combined to form a table pool. The table pool corresponds to a physical table on the database in which all the records of the allocated pooled tables are stored.

Cluster table Cluster tables contain continuous text, for example, documentation. Several cluster tables can be combined to form a table cluster. Several logical lines of different tables are combined to form a physical record in this table type. This permits object-by-object storage or object-by-object access. In order to combine tables in clusters, at least parts of the keys must agree. Several cluster tables are stored in one corresponding table on the database.

Generated view structure In activation a structure is generated for a view. This structure serves as interface for the runtime environment. It does not generally appear in the ABAP/4 Dictionary.

What is a Data Class?
The Data class determines in which tablespace the table is stored when it is created in the database. What is a Size Category? The Size category describes the probable space requirement of the table in the database. How Many types of size categories and data classes are there? There are five size categories (0-4) and 11 data classes, only three of which are appropriate for application tables:
- APPL0 - Master data (data frequently accessed but rarely updated)
- APPL1 - Transaction data (data that is changed frequnetly)
- APPL2 - Organisational data (customizing data that is entered when system is
configured and then rarely changed)

What are control tables?
The values specified for the size category and data class are mapped to database-specific values via control tables.

What is the function of the transport system and workbench organiser?
The function of the transport system and the Workbench Organizer is to manage any changes made to objects of the ABAP/4 Development Workbench and to transport these changes between different SAP systems.

What is a table pool?
A table pool (or pool) is used to combine several logical tables in the ABAP/4 Dictionary. The definition of a pool consists of at least two key fields and a long argument field (VARDATA).

What are pooled tables? These are logical tables which must be assigned to a table pool when they are defined. Pooled tables can be used to store control data (such as screen sequences or program parameters).

What is a table cluster?
A table cluster combines several logical tables in the ABAP/4 Dictionary. Several logical rows from different cluster tables are brought together in a single physical record. The records from the cluster tables assigned to a cluster are thus stored in a single common table in the database.
Which objects are independent transport objects?
Domains, Data elements, Tables, Technical settings for tables, Secondary indexes for transparent tables,
Structures, Views,
Matchcode objects, Matchcode IDs, Lock objects.

What are the Data types of the external layer?
ACCP, CHAR, CLNT, CUKY,CURR, DATS, DEC, FLTP, INT1,INT2, INT4, LANG, LCHR,LRAW, NUMC, PREC, QUAN,RAW ,TIMS, UNIT, VARC.

What are the Data types of the ABAP/4 layer?
Possible ABAP/4 data types: C: Character. D: Date, format YYYYMMDD. F: Floating-point number in DOUBLE PRECISION (8 bytes). I: Integer. N: Numerical character string of arbitrary length. P: Amount or counter field (packed; implementation depends on hardware platform). S: Time stamp YYYYMMDDHHMMSS. T: Time of day HHMMSS. V: Character string of variable length, length is given in the first two bytes. X: Hexadecimal (binary) storage.

How can we set the tablespaces and extent sizes ?
You can specify the extent sizes and the tablespace (physical storage
area in the database) in which a transparent table is to be stored by setting the size category and data class.

What is a data dictionary ?
Data dictionary is a central source of data in a data management system. Its main function is to support the .It has details about

- What data is contained ?
- What are the attributes of the data ?
- What is the relationship existing between the various data elements ?

What functions does a data dictionary perform ?
In a data management system, the principal functions performed by the data dictionary are
- Management of data definitions
- Provision of information for evaluation
- Support for software development
- Support form documentation
- Ensuring that the data definitions are flexible and up-to-date.

A field containing currency amounts (data type CURR) must be assigned to a reference table and a reference field. Explain.
As a reference table, a system table containing all the valid currencies is assigned or any other table which contains a field with the currency key format. This field is called as reference field. The assignment of the field containing currency amounts to the reference field is made at runtime. The value in the reference field determines the currency of the amount.

What is the significance of Technical settings (specified while creating a table in the data dictionary) ?
By specifying technical settings we can control how database tables are created in the database. The technical settings allows us to - optimize storage space requiremnets
- table access behaviour
- buffering required
- changes to entries logged

What is the significance of Delivery Class ?
- The delivery class controls the degree to which the SAP or the customer is responsible for table maintenance
- whether SAP provides the table with or without contents.
- determines the table type. - determines how the table behaves when it is first installed, at upgrade, when it is transported, and when a client copy is performed.

What is the maximum number of structures that can be included in a table or structure
- Nine.

What are the two methods of modifying Sap standard tables ?
- Append Structures and
- Customizing Includes.

What is the difference between a Substructure and an Append Structure ?
- In case of a substructure, the reference originates in the table itself, in the forma of a statement .include... . - In case of an append structure, the table itself remains unchanged and the refrence originates in the append structure.

What are the two ways for restricting the value range for a domain?

- By specifying fixed values.
- By stipulating a value table.

What is a Match Code ?
Match Code is a tool to help us to search for data records in the system. Match codes are an efficient and user-friendly search aid where key of a record is unknown. What are the two levels in defining a Match Code ?
- Match Code object
- Match Code Id.

What is the maximum number of match code Id's that can be defined for one Match code object ?
- 36. A match code Id is a one character ID which can be a letter or a number.

Can we define our own Match Code ID's for SAP Matchcodes ?
Yes, the numbers 0 to 9 are reserved for us to create our own Match Code IDs for a SAP defined Matchcode object.

What is an Update type with reference to a Match code ID?
If the data in one of the base tables of a matchcode ID changes, the matchcode data has to be updated. The update type stipulates when the matchcode is to be updated and how it is to be done. The update type also specifies which method is to be used for Building matchcodes . You must specify the update type when you define a matchcode ID.

What are conversion routines ?
- Non standard conversions from display format to sap internal format and vice-versa are implemented with so called conversion routines.
Aggregated Objects Views, matchcodes, and lock objects are also called aggregate objects because they are formed from several related tables.

What is a View ?
- A view is a logical view on one or more tables. A view on one or more tables i.e, the data from a view is not actually physically stored instead being derived from one or more tables. A view can be used to summarize data which is distributed among several tables

How many types of Views are there ? - Database View (SE11)
Database views are implement an inner join, that is, only records of the primary table (selected via the join operation) for which the corresponding records of the secondary tables also exist are fetched. Inconsistencies between primary and secondary table could, therefore, lead to a reduced selection set. In database views, the join conditions can be formulated using equality relationships between any base fields. In the other types of view, they must be taken from existing foreign keys. That is, tables can only be collected in a maintenance or help view if they are linked to one another via foreign keys.

- Help View ( SE54)
Help views are used to output additional information when the online help system is called. When the F4 button is pressed for a screen field, a check is first made on whether a matchcode is defined for this field. If this is not the case, the help view is displayed in which the check table of the field is the primary table. Thus, for each table no more than one help view can be created, that is, a table can only be primary table in at most one help view.

- Projection View
Projection views are used to suppress or mask certain fields in a table (projection), thus minimizing the number of interfaces. This means that only the data that is actually required is exchanged when the database is accessed. A projection view can draw upon only one table. Selection conditions cannot be specified for projection views.

Maintenance View ( SE54 )
Maintenance views enable a business-oriented approach to looking at data, while at the same time, making it possible to maintain the data involved. Data from several tables can be summarized in a maintenance view and maintained collectively via this view. That is, the data is entered via the view and then distributed to the underlying tables by the system.

What is Locking ?
When two users simultaneously attempt to access the same data record, this is synchronised by a lock mechanism.
When dialog transactions are programmed, locks are set and released by calling certain function modules. These function modules are generated automatically from the definition of so-called lock objects in the ABAP/4 Dictionary. To synchronize the access to a table by setting and removing locks, a Lock object has to be defined in the ABAP/4 Dictionary. Activating the lock object automatically creates #function modules for setting and removing locks. These function modules must be included when programming interactive transactions.

Lock Mechanism : To set locks, a lock object must be defined in the ABAP/4 Dictionary. In this lock object, those tables in which data records are to be locked by calling a lock are determined. All tables included in a lock object must be connected to each other via foreign keys. The key fields of the tables in a lock object form the Lock arguments for the tables. The lock arguments are the basis for formulating the logical condition for identifying the records to be locked. When activating this lock object, two function modulesB with the names ENQUEUE_ and DEQUEUE_ are generated.

Example :
Problem : You wish to prevent a user from being able to change the name of a course or the name of the professor with responsibility for the course at a time when another user is editing the course description (which contains this information).

Solution : The problem described above can be solved by defining a lock object E_UKURS. This is done by defining primary and secondary tables in the lock object. Table UKURS is check table of table UKRSB, so UKURS should be selected as primary table and UKRSB as secondary table of the lock object. The Lock argument in this case is the field combination FABNR, KRSNR, and SPRAS (i.e Primary Key Combination). The Lock mode Shared is to be selected here. This allows several users to access the data simultaneously in display mode. The lock mode in the generated function modules for setting (ENQUEUE_E_UKURS) and releasing (DEQUEUE_E_UKURS) locks is therefore set to shared as default, but can be overridden by calling the function modules. If the function module ENQUEUE_E_UKURS is called with FABNR = '1' and KRSNR = '3', the record for course 3 in faculty 1 is locked in table UKURS. Furthermore, all the course descriptions for this course are locked in table UKRSB since field SPRAS was not specified when the function module was called. In such cases, the lock is made generically for a field which is not defined. If the function module DEQUEUE_E_UKURS is now called with FABNR = '1', KRSNR = '3' and SPRAS = 'D', the German course description is unlocked. All other course descriptions remain locked.

What is database utility ?
Database utility is the interface between the ABAP/4 Dictionary and the underlying the SAP system. The database utility is the interface between the ABAP/4 Dictionary and the relational database underlying the SAP system. You can call the database utility from the initial screen of the ABAP/4 Dictionary with Utilities ® Database utility. The database utility allows you to create, delete and convert objects from the ABAP/4 Dictionary in the database.

MODULARIZATION

What is Modularization and its benefits?

If the program contains the same or similar blocks of statements or it is required to process the same function several times, we can avoid redundancy by using modularization techniques. By modularizing the ABAP/4 programs we make them easy to read and improve their structure. Modularized programs are also easier to maintain and to update.

How can we create callable modules of program code within one ABAP/4 Program?
A. By defining macros. B. By creating include programs in the library.

What are subroutines?
Subroutines are program modules which can be called from other ABAP/4 programs or within the same program.

What are the types of Subroutines?
A. Internal Subroutines: The source code of the internal subroutines will be in the
same ABAP/4 program as the calling procedure (internal call).
B. External Subroutines: The source code of the external subroutines will be in an
ABAP/4 program other than the calling procedure.

What are the different types of parameters?
Formal parameters: Parameters which are defined during the definition of subroutine with the FORM statement. Actual parameters: Parameters which are specified during the call of a subroutine with the PERFORM statement.

How can one distinguish between different kinds of parameters?
A. Input parameters are used to pass data to subroutines. B. Output parameters are used to pass data from subroutines.

What are the different methods of passing data?
A. Calling by reference: During a subroutine call, only the address of the actual
parameter is transferred to the formal parameters. The formal parameter has no memory of its own, and we work with the field of the calling program within the subroutine. If we change the formal parameter, the field contents in the calling program also change.
B. Calling by value: During a subroutine call, the formal parameters are created as
copies of the actual parameters. The formal parameters have memory of their own. Changes to the formal parameters have no effect on the actual parameters.
C. Calling by value and result: During a subroutine call, the formal parameters are
created as copies of the actual parameters. The formal parameters have their own memory space. Changes to the formal parameters are copied to the actual parameters at the end of the subroutine.
The method by which internal tables are passed is By Reference.

What is the difference between the function module and a normal ABAP/4 subroutine?
In contrast to normal subroutines function modules have uniquely defined interface. Sub routines do not return values.
Sub routines do not return exceptions. Sub routines cannot be tested independently. Declaring data as common parts is not possible for function modules. Function modules are stored in a central library. What is a function group? A function group is a collection of logically related modules that share global data with each other. All the modules in the group are included in the same main program. When an ABAP/4 program contains a CALL FUNCTION statement, the system loads the entire function group in with the program code at runtime. Every function module belongs to a function group.

What is the difference between internal tables and extract datasets?
A. The lines of an internal table always have the same structure. By using extract
datasets, you can handle groups of data with different structure and get statistical figures from the grouped data.
B. You have to define the structure of the internal table at the begining. You need
not define the structure of the extract dataset.
C. In contrast to internal tables, the system partly compresses extract datasets
when storing them. This reduces the storage space required.
D. Internal tables require special work area for interface whereas extract datasets
do not need a special work area for interface.

LOGICAL DATABASE
What are logical databases?
What are the advantages/disadvantages of logical databases? Ans :- A Logical Database is a hierarchical structure of tables. Use the GET statement to process Logical Databases. - LDB consists of logically related tables grouped together ­ used for reading and processing data.
- Advantages = 1. No need of programming for retrieval , meaning for data selection
- 2. Easy to use standard user interface, have check completeness of user input.
Disadvantages = 1. Fast in case of lesser no. of tables But if the table is in the lowest level of hierarchy, all upper level tables should be read so performance is slower.

Preparation of the data records by the L.D.B and reading of the data records in the actual report are accomplished with the command pair.
- Put and Get.

The three main elements of LDB are - Structure, Selections, Database Program.

What sort of tables one can use in designing the hierarchy of a LDB ?
- Tables which are having Foreign key relations.

The structure of Logical Databases relfects the ________________ dependencies of hierarchical tables in the SAP System.
- Foreign key

If you want to improve the response time ( time to access data ) Logical DataBases permits you to achieve this using ______________
- VIEWS.

What are the advantages of Logical DataBases ?
It offers an easy-to-use selection screen.
You can modify the pre-generated selection screen to your needs. It offers check functions to check whether user input is complete, correct, and plausible.
It offers reasonable data selections.
It contains central authorization checks for database accesses.
Enhancements such as improved performance immediately apply to all report programs that use the logical database.

Report FORMATTING

In order to suppress the leading zeros of a number field the keywords used are - NO-ZERO.

The Command that allows for vertical alignment of fields one below the other -UNDER.

In order to concatenate strings only for output purposes the command _________ can be used in conjunction with the 'Write' statement.

NO-GAP.

Data can be moved from one field to another using a 'Write:' Statement and stored in the desired format. True or False.

TRUE.

Write : Date_1 to Date_2 format DD/MM/YY. In order to have boldfaced text as output the command used is

Write : INTENSIFIED. Background and foreground colors can be interchanged using the command Format inverse.

Which datatype cannot be used to define parameters.

Type F.

For each new event, the system resets all formatting options to their default values. TRUE.

The processing block following END-OF-PAGE is processed only if you reserve lines for the footer in the LINE-COUNT option of the REPORT statement.

To execute a page break under the condition that less than a certain number of lines is left on a page is acheived by ________________________.

RESERVE n lines.

What is the limit for the length of a page if the page length is not specified in the report statement.

60,000 Lines.

How can Symbols or R/3 icons be output on the screen?

WRITE AS SYMBOL. WRITE AS ICON.

REPORTING – GENERAL

What are reports? and how do you set up reports?

A report program reads and analyzes data from one or more database tables without modifying the database. Usually, the result of such a report program is in the form of a list which is output to the screen or sent to a printer.

What are the different types of programs?

I   Include Program
M Module Pool
F  Function Modules
S  External Subroutines
1  Online program

Events in Reporting ? Explain ?
The following events occur at runtime of a typical report program which uses logical databases: Get Event

INITIALIZATION
Point before the selection screen is displayed
When you start a program in which a selection screen is defined (either in the program itself or in the linked logical database program), the system normally processes this selection screen first. If you want to execute a processing block before the selection screen is processed, you can assign it to the event keyword INITIALIZATION.

AT SELECTION-SCREEN
Point after processing user input on the selection screen while the selection screen is still active
The event keyword AT SELECTION-SCREEN provides you with several possibilities to carry out processing blocks while the system is processing the selection screen.

START-OF-SELECTION
Point after processing the selection screen
The event START-OF-SELECTION gives you the possibility of creating a processing block after processing the selection screen and before accessing database tables using a logical database. You can use this processing block, for example, to set the values of internal fields or to write informational statements onto the output screen. At the START-OF-SELECTION event, also all statements are processed that are not attached to an event keyword except those that are written behind a FORM-ENDFORM block .

GET
Point at which the logical database offers a line of the database table

The most important event for report programs with an attached logical database is the moment at which the logical database program has read a line from a database table. To start a processing block at this event, use the GET statement as follows:

Syntax

GET

[FIELDS ].

[FIELDS ]. After this statement, you can work with the current line of the database table. The data is provided in the table work area

GET LATE

Point after processing all tables which are hierarchically subordinate to the database table in the structure of the logical database.
To start a processing block at the moment after the system has processed all database tables of a logical database that are hierarchically inferior to a specific database table, use the event keyword GET as follows:

Syntax :

GET LATE [FIELDS ]

In analogy to report programs that use only SELECT statements (see table in Comparison of Access Methods ), the processing block of a GET

LATE statement would appear directly before the ENDSELECT statement in the SELECT loop for the database table.

END-OF-SELECTION
Point after processing all lines offered by the logical database.
To define a processing block after the system has read and processed all database tables of a logical database, use the keyword END-OF-SELECTION. The following events occur during the processing of the output list of a report program: Event keyword

TOP-OF-PAGE
Point during list processing when a new page is started

END-OF-PAGE
Point during list processing when a page is ended
The following events occur during the display of the output list of a report program: Event keyword

AT LINE-SELECTION
Point at which the user selects a line

AT USER-COMMAND
Point at which the user presses a function key or enters a command in the command field.

AT PF
Point at which the user presses the function key with the function code PF

With the selection screen, ABAP/4 offers an interactive element also for report programs. You can define a selection screen without having to bother about all the details required in dialog programming. The selection screen is always processed directly after a report program is started. The user can enter field values and selection criteria on this screen. The main purpose of the selection screen is to enable the user to control the database selections of the report program. If a report program is started from another ABAP/4 program with the SUBMIT statement (see Calling Reports), the selection screen objects also serve as a data interface, With a selection screen defined in the report program, you can enable the user to assign values to variables with the PARAMETERS statement determine selection criteria with the SELECT-OPTIONS statement

How do you read selected lines of database table into an internal table in packages of predefined size?

SELECT * FROM INTO TABLE PACKAGE SIZE .
where 'n' is variable.
Name the WILDCARD characters which are used for comparisions with character strings & numeric strings.
'%' and '_'.

How to specify a client for database table processing.

TABLES SPFLI.
SELECT * FROM SPFLI CLIENT SPECIFIED
WHERE MANDT BETWEEN '001' AND '003'.
...
ENDSELECT.

Activation ­ During activation, the runtime object of aggregate object or tables is created. The runtime object is buffered so that the application program can access it quickly. Runtime object has information about the following objects of table - domain ­ data elements ­ field definition ­ table definition

Lock Mechanism ­ prevents a new database operation being started an existing one has been correctly completed. When conversion is done, lock is created automatically and released only when conversion is successful. Clearing of locks ­ restart adjustment ­ attempt is made to continue conversion at the point of
termination
Cancel adjustment ­ lock entry is simply deleted from table

Version Management functions ­

- Canceling changes ­ reset revised version to active version
- Storing changes ­ active version will be temporarily stored in version
Switching changes ­ switch between active and revised versions

Version catalog ­ list of all existing versions of an object

- Revised version ­ produced when we edit an existing object
- Active version ­ produced when we activate an object
- Temporary version ­ produced when we copy the active version temporarily to the database with store version functions
- Historical versions ­ created when 1. Correction is created 2 correction is
released

Table Buffering : Possible buffering types

- full buffering ­ either, whole table or none of the table is located in the buffer (Tables up to 30 kb done in client dependent fully buffered tables)
- Generic buffering ­ generic areas of the table are fully buffered.
- Generic key ­ left justified section of primary key of a table.
Single record buffering ­ records actually being accessed are loaded to buffers, large records where few records are accessed.

Internal Tables ? Types ?

STANDARD table Key access to a standard table uses a linear search. This means that the time required for a search is in linear relation to the number of table entries. You should use index operations to access standard tables.

SORTED table Defines the table as one that is always saved correctly sorted. Key access to a sorted table uses a binary key. If the key is not unique, the system takes the entry with the lowest index. The runtime required for key access is logarithmically related to the number of table entries.

HASHED table Defines the table as one that is managed with an internal hash procedure You can only access a hashed table using the generic key operations or other generic operations ( SORT, LOOP, and so on). Explicit or implicit index operations (such as LOOP ... FROM oe INSERT itab within a LOOP) are not allowed.

INDEX table A table that can be accessed using an index. Index table is only used to specify the type of generic parameters in a FORM or FUNCTION. That means that you can't create a table of type INDEX. Standard tables and sorted tables are index tables.

Syntax : DATA itab TYPE table type of line type [WITH UNIQUE/NON-UNIQUE KEY ] [Iinitial size n] [WITH HEADER LINE]

What are DATA CLUSTERS ?

You can group any complex internal data objects of an ABAP/4 program together in data clusters and store them temporarily in ABAP/4 memory or for longer periods in databases. You can store data clusters in special databases of the ABAP/4 Dictionary. These databases are known as ABAP/4 cluster databases and have a predefined structure.Storing a data cluster is specific to ABAP/4. Although you can also access
cluster databases using SQL statements, only ABAP/4 statements are able to decode the structure of the stored data cluster.

Describe the functions of the debugger screen.

- Single step(F5) - Use this option to step through the program statement by statement. This allows you to branch into subroutines and function modules, and to execute these routines step by step as well. Once a subroutine or function module has been processed, control returns to the statement following the CALL FUNCTION or PERFORM statement.

- Execute(F6)- Use this option to process a program line by line. All of the statements on the current line are processed in a single step. If you are positioned on a line that calls a subroutine and you choose Execute, the Debugger processes the whole subroutine and then moves on to the line following the subroutine call. This allows you to jump through the statements within the subroutine.

- Return(F7) - The Debugger returns from a routine to the point at which control returns to the main program. Use this option to return from a subroutine, function module, or called program to the calling program.

- Continue(F8)- Use this option to process the program up to the next dynamic or static breakpoint or up to the cursor position. If there are no more breakpoints in the program and no cursor has been set, the system exits debugging mode and executes the rest of the program normally.

- Tables - Display the contents of internal tables.

Problem:How to run a program in background?

Solution :Execute the Report In the selection screen :After filling the screen fields press F9. A screen appears requesting U to print the Background Parameters *Enter the output device(Eg HPLJ /SAP2 etc) *In the spool options Uncheck Print immedietly,Uncheck delete after output,and new spool request. Press enter. Another screen appears with heading start time .U can press start immly ,then save Now the Background job is scheduled for the given program.

To View the status of background Job,The transaction code is SM37. Execute from the resulting screen . Job overview -->From the Job list select U'r program and select Spool from the application toolbar Output Controller :List of Spool Requests Select U'r Spool request and click Display icon from the overview screen . U will be displayed with the List. Caution :See to that the list with does not exceed 255 columns ,If it exceeds the extra columns will be truncated in Background

What are presentation and application servers in SAP?

A presentation server is actually a program named Sapgui.exe. It is usually installed on a user's workstation. Application server is a set of executables that collectively interpret the ABAP/4 programs and manage the input & output for them.

In an ABAP/4 program how do you access data that exists on a presentation server v/s on an application server?

For presentation server use UPLOAD or WS_UPLOAD function modules. For application server use OPEN DATASET, READ DATASET and CLOSE DATASET commands.

Describe the syntax and function of the AUTHORITY CHECK command?

Ans :- AUTHORITY ­ CHECK OBJECT

ID FIELD ID FIELD ... IF SY-SUBRC NE 0. The AUTHORITY-CHECK checks whether a user has the appropriate authorization to execute a particular activity