IBM Mainframe Developer Interview Questions and Answers

Job Control Language (JCL) is used to define and execute jobs on mainframe systems.

• JCL statements are used to specify the job to be executed, including input/output files, program to be run, and other job control parameters.

• Example: //JOBNAME JOB (ACCOUNT), 'DESCRIPTION',CLASS=A,MSGCLASS=X

• JCL statements are written in a specific format with keywords and parameters to define the job steps and execution flow.

• Example: //S

IDCAMS is the utility used to create a GDG.

• IDCAMS is a utility program used in z/OS to define and manage VSAM datasets, including GDGs (Generation Data Groups).

• To create a GDG using IDCAMS, you would typically write a JCL job that includes IDCAMS statements to define the GDG base and generations.

• Example: //STEP1 EXEC PGM=IDCAMS //SYSIN DD * DEFINE GDG(NAME(TEST.GDG) LIMIT(10) SCRATCH)

Mainframe utilities are software programs used for various tasks like data management, job scheduling, and system maintenance.

• IEFBR14 - used for creating empty datasets

• IEBCOPY - used for copying datasets

• IEBGENER - used for generating datasets

• IDCAMS - used for defining and managing VSAM datasets

• DFSORT - used for sorting and merging datasets

Comp is a binary data type with fixed length, while Comp3 is a packed decimal data type with variable length.

• Comp is binary and fixed length, while Comp3 is packed decimal and variable length

• Comp stores data in binary format, while Comp3 stores data in packed decimal format

• Comp uses 4 bytes for each field, while Comp3 uses variable length depending on the precision required

• Example: Comp field with value 1234 will be st...read more

My salary expectation is based on my experience, skills, and the market rate for Mainframe Developers.

• Consider my years of experience in Mainframe development

• Research the average salary for Mainframe Developers in the current market

• Factor in the location and size of the company

Seeking new challenges and opportunities for growth.

• Looking for a more challenging role that allows me to further develop my skills

• Interested in exploring new technologies and methodologies

• Seeking a more supportive and collaborative work environment

• Want to take on more responsibility and leadership opportunities

Join key is a field used to match records from two different data sets in a database or data processing system.

• Join key is used in JOIN operations to combine data from multiple tables based on a common field.

• It is typically used in SQL queries to specify the columns that should be used to match records between tables.

• For example, in a customer and order database, the customer ID could be the join key to link customer i