AS400 Interview Questions- Part2
1. Why should a programmer use
the OVRDBF command?
To override
default values set for the physical file; i.e., to utilize a specific member in
a physical file.
2.Explain about
RTNCSRLOC?
It
will give field name where the cursor is living in a sub-file or a
display-file.
3. How would you
print only last 10 pages of a report?
CHGSPLA command is used. In that
the PAGE RANGE
4. What is a message
file?
It
is used to store all the messages to be sent to programs. It has two parts.
1.
Message ID –7 Character
2.
Message Description
5. What is an
Object?
Anything, which occupies memory, is known as
Object. When you execute a program, object will be created. The object has a
set of attributes, which includes name, type, size, creation data, and a short
description of the object. WRKOBJPDM is used to display all object in a
library. With in the library the object name and its type is Unique
6. What is the purpose of the
CHKOBJ command?
To test for the
existence of and object and to check for object authorization for the user.
7. CRTDUPOBJ –
Explain.
Create
Duplicate Object. To copy an object we use this command.
8. What is the purpose of the
DSPLIBL command?
Displays a list
of all libraries whose objects are available to the interactive job.
9. What is a Library? Explain its types.
Library is an
object of type *LIB that is used to group related objects. Thus library is a
directory to a group of object.
Library is an
open-ended directory.
Library can
never become ‘full’ as it has no finite size.
Library reside
only in system library QSYS.
The order of
library is
System library –
15 nos. e.g. QSYS
Product library
– 1
User library –
25 nos. QTEMP, QGPL are user libraries.
Current library
– 1
ADDLIBLE, RMVLIBLE,
CHGCURLIB, DSPLIBL, EDTLIBL is used to add the content to current
library, remove the content to current library, change current library, display
all library and editing the library respectively.
10. What are user library?
QTEMP,
QGPL and MYLIB
11. What are library list and how many libraries can be in library
list?
The library list
is a list of library, which is to be searched for existence of a file. It
contains four parts, System part, Product part, User part and Current library.
We can place as
many as 40 libraries in a library list. In that 15 as system lib and 25 as user
lib.
The related
commands are EDTLIBL, ADDLIBLE, RMVLIBLE, and DSPLIBL
12. What is current library?
The command to
change a library into current library is CHGCURLIB
The library,
which is always in the top of library list and it, is the first library
searched when a job is executed.
13. What is the purpose of changing current library?
If
you compile a member then we need to change the current library.
14. What two CL commands are usually used to debug a program?
STRDBG and
ADDBKP - Start Dedub abd Add Breakpoint.
15. What CL command is used to
debug a program on-line?
STRISDB - Start Interactive
Debugger
16. How you execute
CL command in RPG?
By using
QCMDEXC command we can execute CL command in RPG.
17. What does UPDPROD *NO and INVOKE PGM *YES mean?
UPDPROD *NO (default) wont update the files used in
the program and *YES will do.
INVOKE PGM *YES (default) will execute the CALLING
program simultaneously and *NO will execute only when the CALL statement is
executed.
18. What is QCMDEXC?
A program that
can be called from an RPG program to execute most
CL commands.
19. Which OS/400 command does not execute in command line?
RTVDTAARA & RTVSYSVAL .For
this you have to declare one to variable
20. How to send
message to the screen by SNDPGMMSG?
By passing the Message file name,
Message ID and Message Data, we can send a message to the screen.
21. What is the
difference between CALL and Transfer Control?
CALL
will transfer the
control according with the CALL STACK
TFRCTL [Transfer Control] will remove
the CALL STACK and transfer the
control to the calling program. The CALL is used to interface between two
different types of programs, whereas TFRCTL is used to call CL programs only.
22. What are the
different Queues available in OS/400?
They are
·
Job Queue
·
Message Queue
·
Output Queue
·
Data Queue
Job Queue: It contains the list of
batch job waiting to be compiled.
Message Queue: It contains various messages to
be sent to programs, procedures or user.
Output Queue: It contains all the spooled
files waiting to print.
Data Queue: It
is a temporary storage. We can able to store and retrieve data. But either once
the data retrieved or the waiting time closed the data will be lost.
Sending a message to a data
queue by QSNDDTAQ, QRCVDTAQ and CLRDTAQ commands.
23. QSNDDTAQ,
QRCVDTAQ Explain.
QSNDDTAQ
is a command, that is used to send a message to other / same program.
QRCVDTAQ
is a command, that is used to receive a message from other / same
program.
24. What are the
mandatory parameters for declaring a Data Q?
These are DataQ Name, Library,
Data, Length of the data and Wait. The Wait is appearing only on the QRCVDTAQ
25. Explain
RUNSQLSTM statement.
It is command, which is used to
store and execute set of sql statements. These statements may be insert or
update or delete. Select statements can’t be used. These to be included with
the source type as sql. Then using strsqlstm to execute the program.
RUNSQLSTM SRCFILE (XXLIB/PF01)
SRCMBR (SQL01)
COMMIT (*NONE)
26. How to create
RPG, RPGILE, CL, CLLE, PF, LF, DSPF and RLU?
CRTRPGPGM
: used to create RPG
CRTCLPGM :
used to create CL program
CRTBNDRPG
: used to create RPGILE
program. (CRTBNDRPG =
CRTRPGMOD + CRTPGM)
CRTBNDCL
:
used to create CLLE program
CRTPF : used to create a PF
CRTLF : used to create a LF
CRTDSPF :
used to create a Display File
27. What is PWRDWNSYS?
The command to power down the AS/400.
28. What is the purpose of the
EDTOBJAUT command?
To permit or exclude user access to
specific objects.
29. What are the tools available in AS/400?
·
Program Development Manager (PDM)
·
Source Entry Utility (SEU)
·
Data File Utility (DFU)
·
Screen Design Aid (SDA)
·
Report Layout Utility (RLU)
The commands to
use these are
STRPDM,
WRKMBRPDM, WRKOBJPDM, WRKLIBPDM, STRSEU, STRDFU, STRSDA and STRRLU
30. Explain the STRSEU command.
To create a new
program or put the last used program in edit Mode
31. What is QTEMP?
A unique
temporary library associated with each job. The object in this library will be
deleted when the workstation signoff.
32. What is PDM?
PDM (Program Development Manager)
is a tool to simplify software development and maintenance and is used to work
with library, objects and file members and also with user defined commands.
WRKLIBPDM
Work With
Library PDM. To work with the objects inside the library, like copy delete the
objects.
The default
parameter is ‘lib *prv’
WRKOBFPDM
Work
With Object PDM. To work with the objects resides in a source physical file
such as rename, copy, delete, edit etc.
WRMBRPDM
Work
With Member PDM. To work with the file members of a source physical file such
as rename, copy, delete, edit etc.
Related
commands are
WRKLIB : To work with the library object in the
system library or if we specify the lib name in the parameter then we can work
with the objects in that specified library.
The default
parameter is ‘lib *libl’
WRKOBJ : To work with the specified object. The
parameter to pass is ‘object name’.
The difference
between WRKOBJPDM and WRKOBJ is the ‘obj attribute’ will not be in WRKOBJ
Obj name ----------
Lib
name *libl
Obj
type *All]
COMMIT (*NONE)
33. Explain
WRKOBJPDM and DSPOBJD
DSPOBJD
if we know library name and object name and we want to know the source physical
file where it is residing then dspobjd with option as services instead of basic
will give the source physical file name.
WRKOBJPDM
is used to list all in particular library. If we want to list all rpgle
programs, then put type as rpgle. It is just like a DIR command on DOS.
34. What is job and
explain its type?
Every
piece of work runs on the system is called job.
The
types are
Interactive job
The
job runs on the system after one sign-on the workstation is called interactive
job and it will end when sign-off.
Batch job
It
is the predefined sequence of work submitted to the Job Queue. It wont be
interrupted by the user. Thro’ SBMJOB command we can submit the Batch job to
Job-Queue.
35. How would you
see the Batch job?
Thro’
the command WRKSBMJOB.
36. What are the
attributes for the job?
Job
Number, Job Name and User Name.
37. What is the
Error severity?
Error
Severity determines the level of severity required to terminate the job.
38. What is the error indicator?
In C spec, we
can declare 3-types of indicators. High, Low and Equal. Here Low indicator acts
as error indicator.
HiLoEq
C READ REC1 252627
Here 25 is EOF
reached, 26 is No record found and 27 is Record found
39. What are the authorities in AS/400?
i.
*ALL -has
all authorities
ii.
*CHANGE -has
object operation, read, add, delete and update
iii.
*USE -has
object operation and read
iv.
*EXCLUDE -none
v.
*READ (Read)
vi.
*ADD (Add)
vii.
*UPD (Update)
viii.
*DLT (Delete)
40. How would you
change the authority of an object?
GRTOBJAUT
command will change.
41. What are different database functions?
§ CTROBJ
§ DLTOBJ
§ CHGOBJ
§ RTVOBJ
§ CRTDUPOBJ
No comments