AS/400 Interview Questions Answers-section 3
What are the types of data areas?
Ans:User defined Data Area, Local Data Area (LDA), Group Data Area (GDA), Program Initialization Parameter (PIP) Data Area.
What is LDA?
Ans:LDA is created by the system for each job in the system, including auto-start jobs, jobs started on the system by a reader, and subsystem monitor jobs.
What is the type, length of a LDA?
Ans:*CHAR, 1024 bytes
What is GDA?
Ans:The system creates a GDA when an interactive job becomes group jobs. Only one GDA can exists for group.
How can a data area be locked after being updated?
Ans:Using OUT *LOCK
What is the use of Data Queues?
Ans:Data queue is a type of system object that you can create. Data Queues are used in Program to program communication.
How to create a data queues?
Ans:Using CRTDTAQ command.
What are the valid data types in Data Queue?
Ans:Char, Numeric, and Logical
What are the two types of read performed on data queues?
Ans:Read with lock, and read without lock.
How do you use DEBUG utility?
Ans:STRDBG program-name UPDPROD(*YES)
What is an authorization list?
Ans:A lists of two or more user Ids & their authorities for system resources. The system identifies it an object type *AUTL
How do you grant authority?
Ans:Using GRTOBJAUT command
What are the types of object authorities?
Ans:*USE, *CHANGE, *ADD, *DLT, *READ, *UPD, *ALL, *EXCLUDE, *OBJEXIST, *OBJMGT, *OBJOPR
How do you put jobs in batch mode?
Ans:SBMJOB
What is the use of OVRDBF ?
Ans:You can use the Override with Database file (OVRDBF) command to replace the database file named in a CL program or to change certain parameters of the existing database file.
What is the use of OVRPRTF ?
Ans:Override with Printer file (OVRPRTF) command is used to override certain parameters of the printer files used in the program or to replace the printer file.
How to change file attributes such as size, file wait time, record wait time etc. , permanently?
Ans:Using CHGPF command
What is the use purpose of CRTCMD?
Ans:To create user defined command.
What is class of service ?
Ans:A set of link and node characteristics associated with a session.
How to see active jobs of the system.
Ans:Using WRKACTJOB command
How do you detect unused spool storage?
Ans:Using Reclaim Spool Storage.
What are the functions of Remote Job Entry (RJE) ?
Ans:Allows user of AS/400 system to submit jobs and receive jobs from a host system.
What is the function of RJE Conversion Utility?
Ans:It converts compressed data written to an AS/400 database file to decompressed data written to another AS/400 database, diskette, or device file.
What process the command SBMRJEJOB does?
Ans:Sends RJE input stream to host system
What is journaling & Commitment Control?
Ans:Journaling is a function which records the changes in a file in a journal. These record images are used to recover the changes in the file should the system ends abnormally. Commitment control is a function that allows you to define and process a number of changes to database files as a single unit (transaction).
What is the purpose of STRCMTCTL command?
Ans:Starts commitment control for files that are being journalled.
What are the system objects required for journalling?
Ans:Journal receiver, journal and PFs to be journalled.
What are the different definition levels in Data Description Specifications?
Ans:File level, Record level, Field level, Join level, Keyfield level, Select/Omit level.
What the difference between Source Physical File and Physical File?
Ans:A Source Physical File contains the source for the various objects created this file has specific structure. A Physical File contains data, and the record format can be different for different physical files.
What is an access path?
Ans:The order in which the database fields are organized for processing in the program.
What are all the different types of access path?
Ans:Arrival sequence access path. Keyed sequence access path.
What is the default value for the number of increment for the physical file?
Ans:Three
When does the DFT keyword in PF be used?
Ans:To specify the default value it a field.
How to create a user defined (general) data area?
Ans:Using CRTDTAARA command
What are the different ways to input data into data area?
Ans:CHGDTAARA (using CL)
Using OUT opcode in RPG
How to retrieve data from data area?
Ans:
Using RTVDTAARA command in CL.
Using IN opcode in RPG
What is Spool file, Why is it required?
Ans:A file that holds output data to be processed, such as information waiting to be printed.
What is Job, What are the attributes of a Job?
Ans:
A Job is a basic unit of work on AS/400.
The attributes are:
Job Number Unique system generated sequential number
Job Name Any user defined name (Max 10 char)
User Name Who initiated the job.
What is Job description?
Ans:A Job description defines an environment in which a batch job or an interactive job to be executed.
What is the difference between Interactive & Batch Job?
Ans:
Interactive Job: A Job started for a person who signon to a workstation.
Batch Job : A predefined group of processing actions submitted to the system to be performed.
What is Group Job?
Ans:A Group Job is attached to one workstation and a user. There should be an initial group job and it can be branched to many other group jobs. The group jobs can have different library lists and different output, message queues. Group Job is useful in enhancing the programmers productivity. It is as though logging into the same user-id many times.
What are the two main attributes, which govern the execution of a job?
Ans:Run time priority and Time slice
What is Sub-System?
Ans:Sub-Systems are specific user defined partitions of the CPU where various jobs may be executed. One subsystem can have more than one active job at a time.
What is a Device file?
Ans:A device file contains the description of how data is to be presented to a program from a device or vice versa. Device file can be Printer, Disk, Tape and Remote system.
What is the maximum number of key fields allowed defining in a physical file?
Ans:120
What is acronym of RPG?
Ans:Report Program Generator
What is the native language of AS/400?
Ans:RPG/400
Why RPG/400 is famous?
Ans:
* Easy to code and analyze.
* Supports externally described files.
What is an ICF file?
Ans:A device file that allows a program on the system to communicate with program in other system.
What is a message file?
Ans:It is a file which contains the messages of an application. For example all RPG/400 messages are stored in a file, all COBOL/400 messages are stored in a file.
What is a job log?
Ans:A record of request submitted to system be a job. The message related to the requests, and action performed by the system on the log. The system program maintains it.
What is the purpose of OPNQRYF (Open Query File)?
Ans:OPNQRYF is used to select certain records of the database file based on the QRYSLT (Query select ) condition.
How to create files dynamically without DDS?
Ans:Through OPNQRYF
What command must be executed before executing OPNQRYF command?
Ans:OVRDBF (Override Data base file)
What is Data Area?
Ans:Data area is an object used to hold data for access by any job running on the system. A data area can be locked to a single user, thus preventing other users from processing at the same time.
What are the types of data areas?
Ans:User defined Data Area, Local Data Area (LDA), Group Data Area (GDA), Program Initialization Parameter (PIP) Data Area.
What is LDA?
Ans:LDA is created by the system for each job in the system, including auto-start jobs, jobs started on the system by a reader, and subsystem monitor jobs.
What is the type, length of a LDA?
Ans:*CHAR, 1024 bytes
What is GDA?
Ans:The system creates a GDA when an interactive job becomes group jobs. Only one GDA can exists for group.
How can a data area be locked after being updated?
Ans:Using OUT *LOCK
What is the use of Data Queues?
Ans:Data queue is a type of system object that you can create. Data Queues are used in Program to program communication.
How to create a data queues?
Ans:Using CRTDTAQ command.
What are the valid data types in Data Queue?
Ans:Char, Numeric, and Logical
What are the two types of read performed on data queues?
Ans:Read with lock, and read without lock.
How do you use DEBUG utility?
Ans:STRDBG program-name UPDPROD(*YES)
What is an authorization list?
Ans:A lists of two or more user Ids & their authorities for system resources. The system identifies it an object type *AUTL
How do you grant authority?
Ans:Using GRTOBJAUT command
What are the types of object authorities?
Ans:*USE, *CHANGE, *ADD, *DLT, *READ, *UPD, *ALL, *EXCLUDE, *OBJEXIST, *OBJMGT, *OBJOPR
How do you put jobs in batch mode?
Ans:SBMJOB
What is the use of OVRDBF ?
Ans:You can use the Override with Database file (OVRDBF) command to replace the database file named in a CL program or to change certain parameters of the existing database file.
What is the use of OVRPRTF ?
Ans:Override with Printer file (OVRPRTF) command is used to override certain parameters of the printer files used in the program or to replace the printer file.
How to change file attributes such as size, file wait time, record wait time etc. , permanently?
Ans:Using CHGPF command
What is the use purpose of CRTCMD?
Ans:To create user defined command.
What is class of service ?
Ans:A set of link and node characteristics associated with a session.
How to see active jobs of the system.
Ans:Using WRKACTJOB command
How do you detect unused spool storage?
Ans:Using Reclaim Spool Storage.
What are the functions of Remote Job Entry (RJE) ?
Ans:Allows user of AS/400 system to submit jobs and receive jobs from a host system.
What is the function of RJE Conversion Utility?
Ans:It converts compressed data written to an AS/400 database file to decompressed data written to another AS/400 database, diskette, or device file.
What process the command SBMRJEJOB does?
Ans:Sends RJE input stream to host system
What is journaling & Commitment Control?
Ans:Journaling is a function which records the changes in a file in a journal. These record images are used to recover the changes in the file should the system ends abnormally. Commitment control is a function that allows you to define and process a number of changes to database files as a single unit (transaction).
What is the purpose of STRCMTCTL command?
Ans:Starts commitment control for files that are being journalled.
What are the system objects required for journalling?
Ans:Journal receiver, journal and PFs to be journalled.
What are the different definition levels in Data Description Specifications?
Ans:File level, Record level, Field level, Join level, Keyfield level, Select/Omit level.
What the difference between Source Physical File and Physical File?
Ans:A Source Physical File contains the source for the various objects created this file has specific structure. A Physical File contains data, and the record format can be different for different physical files.
What is an access path?
Ans:The order in which the database fields are organized for processing in the program.
What are all the different types of access path?
Ans:Arrival sequence access path. Keyed sequence access path.
What is the default value for the number of increment for the physical file?
Ans:Three
When does the DFT keyword in PF be used?
Ans:To specify the default value it a field.
How to create a user defined (general) data area?
Ans:Using CRTDTAARA command
What are the different ways to input data into data area?
Ans:CHGDTAARA (using CL)
Using OUT opcode in RPG
How to retrieve data from data area?
Ans:
Using RTVDTAARA command in CL.
Using IN opcode in RPG
What is Spool file, Why is it required?
Ans:A file that holds output data to be processed, such as information waiting to be printed.
What is Job, What are the attributes of a Job?
Ans:
A Job is a basic unit of work on AS/400.
The attributes are:
Job Number Unique system generated sequential number
Job Name Any user defined name (Max 10 char)
User Name Who initiated the job.
What is Job description?
Ans:A Job description defines an environment in which a batch job or an interactive job to be executed.
What is the difference between Interactive & Batch Job?
Ans:
Interactive Job: A Job started for a person who signon to a workstation.
Batch Job : A predefined group of processing actions submitted to the system to be performed.
What is Group Job?
Ans:A Group Job is attached to one workstation and a user. There should be an initial group job and it can be branched to many other group jobs. The group jobs can have different library lists and different output, message queues. Group Job is useful in enhancing the programmers productivity. It is as though logging into the same user-id many times.
What are the two main attributes, which govern the execution of a job?
Ans:Run time priority and Time slice
What is Sub-System?
Ans:Sub-Systems are specific user defined partitions of the CPU where various jobs may be executed. One subsystem can have more than one active job at a time.
What is a Device file?
Ans:A device file contains the description of how data is to be presented to a program from a device or vice versa. Device file can be Printer, Disk, Tape and Remote system.
What is the maximum number of key fields allowed defining in a physical file?
Ans:120
What is acronym of RPG?
Ans:Report Program Generator
What is the native language of AS/400?
Ans:RPG/400
Why RPG/400 is famous?
Ans:
* Easy to code and analyze.
* Supports externally described files.
What is an ICF file?
Ans:A device file that allows a program on the system to communicate with program in other system.
What is a message file?
Ans:It is a file which contains the messages of an application. For example all RPG/400 messages are stored in a file, all COBOL/400 messages are stored in a file.
What is a job log?
Ans:A record of request submitted to system be a job. The message related to the requests, and action performed by the system on the log. The system program maintains it.
What is the purpose of OPNQRYF (Open Query File)?
Ans:OPNQRYF is used to select certain records of the database file based on the QRYSLT (Query select ) condition.
How to create files dynamically without DDS?
Ans:Through OPNQRYF
What command must be executed before executing OPNQRYF command?
Ans:OVRDBF (Override Data base file)
What is Data Area?
Ans:Data area is an object used to hold data for access by any job running on the system. A data area can be locked to a single user, thus preventing other users from processing at the same time.