Mainframe Interview Questions and Answers, Mainframe Interview Questions and Answers Freshers, Mainframe Interview Questions and Answers, Mainframe Interview Questions

Before getting on to the Mainframe interview questions, the student must know that the Mainframe is a continuously varying field which needs the students as well as professionals to upgrade their skills with the new features and knowledge, to get fit for the jobs associated with Mainframe. This post related to Mainframe Interview Questions and Answers, Mainframe Interview Questions and Answers Freshers, Mainframe Interview Questions and Answers, Mainframe Interview Questions will help you let out find all the solutions that are frequently asked in you upcoming Mainframe interview.

Over thousands of vacancies available for the Mainframe developers, experts must be acquaintance with all the component of Mainframe technologies. This is necessary for the students in order to have in-depth knowledge of the subject so that they can have best employment opportunities in the future. Knowing every little detail about Mainframe is the best approach to solve the problems linked with problem.

APTRON has spent hours and hours in researching about the Mainframe Interview Questions and Answers, Mainframe Interview Questions and Answers Freshers, Mainframe Interview Questions and Answers, Mainframe Interview Questions that you might encounter in your upcoming interview.  All these questions will alone help you to crack the interview and make you the best among all your competitors.

First of all, let us tell you about how the Mainframe technology is evolving in today’s world and how demanding it is in the upcoming years. In fact, according to one study, most of the companies and businesses have moved to the Mainframe. Now, you cannot predict how huge the future is going to be for the people experienced in the related technologies.

Hence, if you are looking for boosting up your profile and securing your future, Mainframe will help you in reaching the zenith of your career. Apart from this, you would also have a lot of opportunities as a fresher.

These questions alone are omnipotent. Read and re-read the questions and their solutions to get accustomed to what you will be asked in the interview. These Mainframe interview questions and answers will also help you on your way to mastering the skills and will take you to the giant world where worldwide and local businesses, huge or medium, are picking up the best and quality Mainframe professionals.

This ultimate list of best Mainframe interview questions will ride you through the quick knowledge of the subject and topics like Mainframe application program, DB2 / UDB administration, CICS administration. This Mainframe interview questions and answers can be your next gateway to your next job as a Mainframe expert.

These are very Basic Mainframe Interview Questions and Answers for freshers and experienced both.

Q1: What is DRDA ?
A1: DRDA stands for Distributed Relational Database Architecture. DRDA is a connection protocol for relational database processing which IBM and vendor databases use. It consists of rules for communication between a remote relational DBMS and the application.

Q2: What is the need of running runstats in the test environment?
A2: It is for clearing the default values from the catalog columns. Because if the columns have default values; then the result might not be an expected one.

Q3: Explain foreign keys?
A3: Foreign keys are properties of a particular table having matching entries to a primary key in some another table. This results in the formation of a relation between the two tables.

Q4: What is the function of DBCTL?
A4: It is used to access IMS files for CICS Transactions and it is an address space. PSBs, DBDs, IMS files and ACBs are fixed into DBCTL for file access. Now if an IMS call is generated by a CICS program the processing gets transferred to DBCTL to be carried, and the result is sent as reply.

Q5: What are the different types of Table spaces?
A5: There are three table spaces, namely:

  • Simple
  • Segmented
  • Partitioned

Q6: How are composite and multiple indexes different?
A6: Multiple index are two indexes, one each for a column of the same table. Composite index is only one index, which consists of combined values of 2 columns of a table.

Q7: Explain lock contention?
A7: The DBD only allows entry to one object at a particular time. Lock contention is said to happen when more than one object seeks permission for execution simultaneously.

Q8: Name and explain the type of locks?
A8: There are three types of lock, namely:

  • Shared – This type of lock permits two or more programs to read from the locked space but does not allow them to change it.
  • Update – This lock is more lenient. It permits the program to read and change the locked space.
  • Exclusive – This lock restricts all users from accessing the locked space.

Q9: What will happen if both STEPLIB and JOBLIB are specified?
A9: JOBLIB is a Data Definition statement. It determines the location of the program, which called the EXEC statement. JOBLIB applies to all steps present in that whole job. It is not possible to use it for catalogued procedures. STEPLIB is very similar JOBLIB. It determines the dataset in which the program exists. It applies only to one step and not the entire job. STEPLIB can be used at any position in the job step and can also be used for catalogued procedures.

In a situation when both STEPLIB and JOBLIB are specified, JOBLIB will be ignored by the system.

Q10: What is COMP-1? COMP-2?
A10: COMP-1 – Single precision floating point. Uses 4 bytes.

COMP-2 – Double precision floating point. Uses 8 bytes.

Q11: What is the difference between SEARCH and SEARCH ALL?
A11: SEARCH – is a serial search.

SEARCH ALL – is a binary search & the table must be sorted ( ASCENDING/DESCENDING KEY clause to be used & data loaded in this order)

before using SEARCH ALL.

Q12: What is binary search?
A12: Search on a sorted array. Compare the item to be searched with the item at the center. If it matches, fine else repeat the process with the left half or the right half depending on where the item lies.

Q13: How many bytes will a S9(8) COMP field occupy ?
A13: 4 bytes.

Q14: In the JCL, how do you define the files referred to in a subroutine ?
A14: Supply the DD cards just as you would for files referred to in the main program.

Q15: How is sign stored in a comp-3 field?
A15: It is stored in the last nibble. For example if your number is +100, it stores hex 0C in the last byte, hex 1C if your number is 101, hex 2C if your number is 102, hex 1D if the number is -101, hex 2D if the number is -102 etc…

Q16: What is 77 level used for ?
A16: Elementary level item. Cannot be subdivisions of other items (cannot be qualified), nor can they be subdivided themselves.

Q17: What are the different data types available in COBOL?
A17: Alpha-numeric (X), alphabetic (A) and numeric (9).

Q18: What does the INITIALIZE verb do?
A18: Alphabetic, Alphanumeric fields & alphanumeric edited items are set to SPACES.

Numeric, Numeric edited items set to ZERO.

FILLER , OCCURS DEPENDING ON items left untouched.

Q19: What Is Full Form Of Spool?
A19: To spool means “to operate (an input/output device) by using buffers in main and secondary storage.” Not sure if there is any full form.

If you meant SDSF, it stands for sytem display and search facility.

Q20: How To Define A Directory And What Is The Structure And Definition For The Same?
A20: As in DIRECTORY we can store files as well as another DIRECTORY which includes other files but PDS includes only mebers not another PDS inside it

Q21: How To Send A Sms To A Mobile Through Mainframe Mvs?
A21: SMS in mainframe is Storage Management System. I hope it has nothing to do with telephone SMS.

Regarding the Storage Management System, I can say something soon.

Q22: What Is The Panel Name Of Ispf Primary Option Menu?
A22: Panel name is ISPf/PDF primary option menu

Q23: What Is Basic Difference Between “directory” And “pds” In Ibm Mainframe?
A23: A PDS or Partitioned Data Set is a dataset containing multiple members, each of which holds a separate sub-data set, similar to a directory in other types of file systems. This type of dataset is often used to hold executable programs (load modules), source program libraries (especially Assembler macro definitions). A PDS is most somewhat analogous to a Zip file on microcomputers, except the files stored in a PDS are not compressed.

The Partitioned Data Set can only allocate on a single volume with the maximum size of 65536 tracks. Besides members, a PDS consists also of their directory. Each member can be accessed directly using the directory structure. Once a member is located, the data stored in that member is handled in the same manner as a PS (sequential) data set.

Q24: What Is The Size Of The Address Space In Kbs For 16 Bit Address Space?
A24: The size of address space for 16 bit address space is 64kb

For s/370 the address space 21 bit- 16MB
For s370XA and EXA address space is 31 bit- 2GB

Q25: What Is The Facility That Allows Mainframes To Be Partitioned Into Lapars? A.z/os C.vitual Storaged.coupling Facility

  • Z/os
  • PR/sm
  • Vitual storage
  • Coupling facility
  • PR/sm

Mainframe Conclusion Interview FAQs

We know the list of Mainframe Interview Questions and Answers, Mainframe Interview Questions and Answers Freshers, Mainframe Interview Questions and Answers, Mainframe Interview Questions is overwhelming but the advantages of reading all the questions will maximize your potential and help you crack the interview. The surprising fact is that this Mainframe interview questions and answers post covers all the basic of the Mainframe technology and you have to check out the FAQs of different components of Mainframe too.

However, you will be asked with the questions in the interview related to the above mentioned questions. Preparing and understanding all the concept of Mainframe technology will help you strengthen the other little information around the topic.

After preparing these interview questions, we recommend you to go for a mock interview before facing the real one. You can take the help of your friend or a Mainframe expert to find the loop holes in your skills and knowledge. Moreover, this will also allow you in practicing and improving the communication skill which plays a vital role in getting placed and grabbing high salaries.

Remember, in the interview, the company or the business or you can say the examiner often checks your basic knowledge of the subject. If your basics is covered and strengthened, you can have the job of your dream. The industry experts understand that if the foundation of the student is already made up, it is easy for the company to educate the employ towards advance skills. If there are no basics, there is no meaning of having learnt the subject.

Therefore, it’s never too late to edge all the basics of any technology. If you think that you’ve not acquired the enough skills, you can join our upcoming batch of Mainframe Training in Noida. We are one of the best institute for Mainframe in noida which provide advance learning in the field of Mainframe Course. We’ve highly qualified professionals working with us and promise top quality education to the students.

We hope that you enjoyed reading Mainframe Interview Questions and Answers, Mainframe Interview Questions and Answers Freshers, Mainframe Interview Questions and Answers, Mainframe Interview Questions and all the FAQs associated with the interview. Do not forget to revise all the Mainframe interview questions and answers before going for the Mainframe interview. In addition to this, if you’ve any doubt or query associated with Mainframe, you can contact us anytime. We will be happy to help you out at our earliest convenience. At last, we wish you all the best for your upcoming interview on Mainframe Technology.


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