Top 11 JCL Tough Interview Questions

Here are tough JCL interview questions asked in many interviews. These questions are handy for your project and interviews as well.


11 JCL Tough Interview Questions (Tricky mainframe interview questions and answers)

11 JCL Tough Interview Questions

Q1). You have created a Proc. You need to put it in SYS.PROCLIB. How do you do this?

A1). Use IEBUPDTE utility:

A) //Step01 Exec Pgm=Abcd
//Filein     DD

Q2). If you do not give DSN name, what will happen?

A2). MVS will treat this as temporary data set. The other way is:

A). //Filein DD  DSN=&&tttttt

Q3). FORCE along with DELETE in GDG?

A3). It will remove the GDG from catalogue.

Q4). REGION=50K, I was given in the JOB statement. What is the meaning of it?

A4). Then memory of 50K will be distributed to each step.

Q5). DFSORT JOINKEYS- What does it do?

A5). You can use it for paired, unpaired, with or without duplicates handling for data in input files.

Q6). SE37 and SB37 and SD37 – Differences between these three?

A6). SB37 and SD37 => Space related to PDS SE37=> Volumes related to Tape dataset.

Q7). What parameters you cannot code in the PROC?

A7). You can’t code the following in the PROC:

JES2 statements
JES3 statements

Q8). How many steps can code in a PROC?

A8). Maximum of 255 job steps we can code in a PROC.

Q9). GDG is created in before step, and if you give OLD, in next step for the same GDG, what you need to change?

A9) You need to change version number.

Q10). MSGLEVEL If you do not give, what will happen?

A10). By default all the statements and messages are written to the SPOOL.

Q11). LIKE=TEST.DATA , what is the meaning of it?

A11). You’ll use this parameters when you want the same PDS parameters (TEST.DATA).

Additional Questions

The CNTL statement in JCL

Program control statements supply control information for a subsystem. A subsystem can require one or more program control statements. The one or more statements must be immediately preceded by a CNTL statement and immediately followed by an ENDCNTL statement.

Sample JCL


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Author: Srini

Experienced software developer. Skills in Development, Coding, Testing and Debugging. Good Data analytic skills (Data Warehousing and BI). Also skills in Mainframe.