10+ Infosys Mainframe Developer Interview Questions and Answers

comp and comp3 are data types used in mainframe programming.

• comp is a binary data type that uses one byte for each digit.

• comp3 is a packed decimal data type that uses half a byte for each digit.

• comp3 is more space-efficient but requires additional processing for arithmetic operations.

• comp3 can store both positive and negative numbers, while comp can only store positive numbers.

A cursor in databases is a pointer that allows for traversal and manipulation of query results.

• A cursor is used to retrieve and process individual rows returned by a query.

• It allows for sequential access to query results, enabling operations like fetching, updating, and deleting rows.

• Cursors are commonly used in programming languages like SQL to work with result sets.

• For example, in a banking application, a cursor can be used to iterate through a list of customer transactions...read more

Static calls are resolved at compile time, while dynamic calls are resolved at runtime.

• Static calls are resolved at compile time based on the declared type of the object being called.

• Dynamic calls are resolved at runtime based on the actual type of the object being called.

• Static calls are faster but less flexible, while dynamic calls are slower but more flexible.

• Example: In a static call, the method to be called is determined by the compiler. In a dynamic call, the method to ...read more

Null variables in COBOL DB2 programs can be handled using NULL indicators and COALESCE function.

• Use NULL indicators to check if a variable is null before processing it.

• Use COALESCE function to replace null values with a default value.

• Handle null variables carefully to avoid runtime errors.

The waterfall model is a linear sequential software development process where progress flows in one direction like a waterfall.

• Involves distinct phases such as requirements, design, implementation, testing, and maintenance.

• Each phase must be completed before moving on to the next phase.

• Changes are difficult to implement once a phase is completed.

• Example: Traditional software development approach where requirements are gathered first, followed by design, coding, testing, and d...read more

Control over job execution can be achieved through job scheduling, monitoring, and automation.

• Use job scheduling tools like Control-M or CA Workload Automation to manage job execution.

• Monitor job progress and status using tools like IBM Tivoli Monitoring or Nagios.

• Automate job execution and error handling with scripts or custom programs.

• Implement job dependencies to ensure proper sequencing and execution.

• Set up alerts and notifications for job failures or delays.

I am using Agile methodology for software development.

• Agile methodology focuses on iterative development and collaboration between cross-functional teams.

• It emphasizes adaptability to changes in requirements and continuous improvement.

• Examples of Agile practices include Scrum, Kanban, and Extreme Programming (XP).

Index is the position of an element in an array, while subscript is the variable used to access elements in an array.

• Index is a fixed value that represents the position of an element in an array.

• Subscript is a variable that is used to access elements in an array.

• Example: arr[2] - '2' is the index, while '2' is the subscript.

Agile framework is a project management approach that emphasizes flexibility, collaboration, and incremental development.

• Agile framework involves breaking down projects into smaller tasks called sprints

• It promotes frequent communication and collaboration among team members

• Allows for flexibility and adaptability to changes in requirements

• Examples of Agile frameworks include Scrum, Kanban, and Extreme Programming

SPUFI stands for SQL Processing Using File Input. It is a tool used to execute SQL queries in DB2 databases.

• SPUFI is a menu-driven tool provided by IBM for executing SQL queries in DB2 databases.

• It allows users to interactively execute SQL queries and view the results.

• SPUFI can be used to test SQL statements before embedding them in application programs.

• It is commonly used by developers and database administrators for ad-hoc querying and testing.

• Example: Using SPUFI, a develo...read more

Abend SOC4 is a system completion code indicating a protection exception error in a mainframe program.

• Check for invalid data or address in the program

• Review the program logic for any potential issues

• Ensure proper handling of data and memory allocation

• Use debugging tools like IPCS to analyze the error

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 stored as x'00000004D2' in hexadecimal, while Comp3 field wi...read more