Q. What is the use of 'outerjoin' ans. With the use of outer join you can join the tables even there
is no entry in all the tables used in the view.
In case of inner join there should be an entry in al the
tables use in the view.
Q. When to use logical database? ans. Advantage of Logical databases:
less coding s reQuired to retrieve data compared to normal
internel tables.
Tables used LDB are in hierarchial structure.
Q. What is the use of 'table index'? ans .Index is used for faster access of data base tables.
Q. What is the use of 'FOR ALL ENTRIES'? ans. To avoid nested select statements we use SELECT FOR ALL ENTRIES
statement.
If there r more than 10000 records SELECT FOR ALL ENTRIES is
used.
Performance wise SELECT FOR ALL ENTRIES is better to use.
Q. Can you set up background
processing using CALL TRansACTION? ans. Yes,Using No Screen Mode.
Q. What are table buffers? ans. Table buffers reside locally on each application server in
the system. The data of buffered tables can thus be accessed
directly from the buffer of the application server. This avoids
the time-consuming process of accessing the database. Buffering
is useful if table needs to be accessed more no. of times in a
program.
Q. What is client 000 in SAP R/3? ans.. Client 000 is defined as the SAP standard and the customer
cannot change it. This client serves as a copy template for the
creation of further clients.
Q. What are the different type of work
process ? ans. The following work process in SAP R/3
Dialog (D): each dispatcher needs at least 2
dialog work processes (not shown above)
Spool (S): at least 1 per R/3 System (more
than 1 per dispatcher allowed)
Update (V): at least 1 per R/3 System (more
than 1 per dispatcher allowed)
Background (B): at least 2 per R/3 System
(more than 1 per dispatcher allowed)
EnQueue (E): exactly 1 per R/3 System (only
1 E work process is reQuired and allowed)
Q. How do you start SAP R/3? ans. To start R/3, run the shell script startsap from the
home directory of user <sid>adm. startsap starts the saposcol process, which is the
statistics collector for operating system resource data, if it is
not yet running.
startsap calls the script
startdb, which starts the database if it is not already
started.
startsap then starts the central
instance.
The R/3 System administrator can start
additional instances and application servers. To start the
instances independently of the database, use the script
startsap.
startsap has the following options:
startsap r3: Checks if
the database is running; if it is, only the instance is started
startsap db: Starts only
the database
startsap all: Default
entry; starts both the database and the R/3 instance
Q. In what seQuence are profile parameter
read? ans. R/3 processes read the appropriate parameters from a C
source in the R/3 kernel
The default profile /usr/sap/<SID>/SYS/profile/DEFAULT.PFL
is read; profile values already defined in the C source are
replaced with the values in the default profile
The instance profile /usr/sap/<SID>/SYS/profile/<SID>_<instance>_<hostname>
is read; profile values already defined in the default profile
or in the C source are replaced with the values defined in the
instance profile
This procedure ensures that system parameter
values reflect the instance profile and the values in the
default profile and the C source.
Q. What are the step involved before
stopping R/3 system? ans. Before stopping any R/3 system following steps are basic
steps to be performed.
Before the R/3 System is stopped, the R/3
System administrator should check the:
Check if any background jobs from any
application server are active or have been triggered externally.
Use transaction SM37
Check if the background work process BTC is
running in any application server.
Check if any update records are open when the
system is stopped, the records are rolled back and set to status
init. At startup, the records are processed again.
The administrator must decide whether to
interrupt the jobs or wait until they are finished.
Give system users advance warning of the
system shutdown. To create a system message, you can use
transaction SM02.
Before shutting down the system, use
transaction SM04 to check whether users are still
logged on, and ask them to log off.
The R/3 System administrator and
administrators of external systems should also inform one
another about data transfers between their respective systems.
