10+ Vibrant Ndt Services Interview Questions and Answers

Explaining the use of NULL indicator and VSAM file in Mainframe development and resolving SOC7 abend.

• NULL indicator is used to indicate the absence of data in a field

• VSAM file is used to store and retrieve data in a program

• SOC7 abend occurs due to invalid numeric data and can be resolved by identifying and correcting the error

• NULL indicator can be checked using IF statement or COBOL verb SET

• VSAM file can be accessed using COBOL verbs like READ, WRITE, START, etc.

Using cursor in COBOL program, difference between cursor and SQL, and when to use JOINKEYS.

• Cursor is used to fetch data from a database table in COBOL program.

• SQL is a language used to interact with databases, while cursor is a mechanism to fetch data from a database table.

• JOINKEYS is used to join two or more files based on a common key.

• JOINKEYS is used when the files are too large to fit in memory.

• JOINKEYS is used when the files are sorted in ascending or descending order.

COBOL has different levels such as level 01, level 77, etc. for defining data structures and variables.

• Level 01 is used for defining record structures.

• Level 77 is used for defining elementary data items.

• Level 88 is used for defining condition names.

• Level 66 is used for renaming data items.

• Level 88 is used for defining condition names.

Rename is used to change the name of a data item while redefine is used to change the structure of a data item.

• Rename is used to change the name of a data item without changing its structure

• Redefine is used to change the structure of a data item without changing its name

• Example: In COBOL, renaming a data item involves using the RENAMES clause, while redefining a data item involves using the REDEFINES clause

IDCAMS utility is used for creating GDG (Generation Data Group)

• IDCAMS utility is used to define, alter, and delete GDGs

• Syntax for defining GDG: DEFINE GDG(NAME(dataset.name) LIMIT(n) SCRATCH)

• Example: DEFINE GDG(NAME(TEST.GDG) LIMIT(5) SCRATCH)

SORT operations in JCL

• SORT is used to arrange data in a specific order

• SORT can be used to remove duplicates from data

• SORT can be used to merge multiple files into one

• SORT can be used to select specific records based on a condition

Static call is resolved at compile time, while dynamic call is resolved at runtime.

• Static call is determined at compile time based on the declared type of the object.

• Dynamic call is determined at runtime based on the actual type of the object.

• Static call is faster but less flexible, while dynamic call is slower but more flexible.

The SORT command in Mainframe can be used to search for a string.

• Use the SORT command with the FIND keyword followed by the string you want to search for.

• Specify the input file and output file for the search operation.

• Example: SORT FILE(INPUT) USING(CTL1) COPY FIND FIRST 'SEARCHSTRING' OUTPUT FILE(OUTPUT)

COBOL is a high-level programming language used for business applications on mainframe computers.

• COBOL stands for Common Business-Oriented Language.

• It was designed in 1959 by CODASYL and is primarily used in finance, insurance, and government sectors.

• COBOL programs are divided into four divisions: Identification, Environment, Data, and Procedure.

• It uses English-like syntax and is known for its readability and self-documenting nature.

• Example: DISPLAY 'Hello, World!'

Mainframe modernization process involves updating legacy systems to newer technologies while preserving critical business logic.

• Assess current mainframe environment and identify areas for modernization

• Develop a modernization strategy, including choosing the right technology stack

• Migrate data and applications to the new platform while ensuring minimal disruption to business operations

• Test the modernized system thoroughly to ensure functionality and performance

• Train staff on th...read more

Sort JCL utilities are used to sort data in Mainframe environment based on specific criteria.

• Use SORT utility in JCL to sort data in ascending or descending order

• Specify the key fields to sort on in the SORT statement

• Use INCLUDE and OMIT statements to filter data before sorting

• Use JOINKEYS utility to merge two or more sorted datasets based on key fields

Temporary files in JCL are used to store intermediate data during job execution.

• Temporary files are defined using DD statements in JCL.

• They are typically used to store data that needs to be processed or manipulated before being written to permanent files.

• Temporary files are often allocated with DISP=(MOD,DELETE) to ensure they are deleted after job completion.