8/2/2019 Important Terms in SAP That Should Be Know

1/2

Message Server: is used to make Communication between different Application Server.Its Role to transfer the Request from one Application to Another with in the stytem.

User Context Area : is Defined As a Temporary Memory area that contain Informations

Information about users. It is used throughout the program processing. when a user logon, a userContext allocated for that logon. When they logoff memory assigned to them is Released.

Roll area : is memory area which is allocated by work processes for program instance. Each timeA user starts program, a roll area is created for the instance of that program.

Dialog Step : is the Processing which is used to navigate from one screen to Another Screen.This includes processing that takes place after that user issues a request.

Dispatcher : It Managesthe Resources ofR3 Application. Assigning of Work processes. Managementof Buffer in the main memory.

Work Processes :A work process is a program in charge of executing the R/3 application tasks. Eachwork process acts as a specialized system service.Work processes make use of two special areas:paging and roll. Thepaging area holds application program data such as internal tables orreport listings. The roll area holds the user context data.

ITS : Internet Transaction Server. It provides an Interface between web server and SAP internetApplication Component . It Changes the data in screen of R/3 system into HTML Format and Vice-Versa.It is very Helpful inDeveloping and testing Full-Fledge Web Transaction.

LUW : is a logical unit of work which Work as a locking mechanism to protect the transaction'sintegrity.A LUW is a set of steps within a transaction, and all of those steps must be correctly completed togo ahead with the transaction logic. If there are errors before the end of the transactions, the current LUWis canceled, but not the previous ones.

There are 2 types of LUW In SAP.

1)Database Luw : It is the method that ensures the consistency of data in the database. LUW is aninseparable sequence of database operations that ends with a Database commit. once a database LUW issuccessfully executed then database will become consistent. Database LUW is either fully executed or notat all.In Case any error occurs with in database will go back in the original state.

2)SAP LUW : It is a logical Unit Comprising various dialog steps.in SAP LUW, changes to databasehave been made in single database LUW. It can be executed using a sequence a different work processesand handle many dialog step.

Different Lock Modes

Exclusive Lock ( Type E ) : Exclusive lock do not allow other users to change or modify the datawhile it is being locked by one user. Only one user at a time can read or process the locked data. furtherrequest for exclusive lock or shared lock is not accepted.

Shared Lock ( Type S ) : Shared Lock in this mode more than one user read the same data at thesame time . When the user changes the data then another user can no longer access this data. Other usercannot set exclusive lock when shared lock in progress.

8/2/2019 Important Terms in SAP That Should Be Know

2/2

Exclusive But Not Cummulative ( Type X )Exclusive but not cumulative can be allowed onlyonce in the same transaction. It cannot be allowed more than once like exclusive lock on the sametransaction. Request for the lock cannot be accepted if the exclusive lock is already set on the transaction.

BDC Batch Data Communication : It is used for uploading large data into SAP system.It is

done with the help of Batch data Programming. It simulates user query from transactional screen throughan Abap Program. Used for regular transfer of data from non-SAP system to SAP system.It is not used forReal-Time data transfer.It is mainly used for one time import of data from a legacy system into a newlyinstallaed R/3 System.

LSMW : is a Legacy system Migration Workbench which is R/3 based tool that is helpful in transferringdata from non-SAP system in to SAP system. The data which is transferred to SAP system is through

Batch input , direct input, BAPI( Business Application Programming Interface ) .