Which file processing technique is suitable when you need to read records in the order they were added to the file?
- Dynamic file processing
- Indexed file processing
- Relative file processing
- Sequential file processing
Sequential file processing in COBOL is suitable when you need to read records in the order they were added to the file. This ensures that records are processed in the same sequence they were inserted, which is beneficial in scenarios where chronological order matters.
You are tasked with building a COBOL application that can generate custom reports based on user input and database data. What COBOL feature or technique would be most suitable for this task?
- Batch Processing
- Dynamic SQL
- Report Writer
- Sequential File Processing
Dynamic SQL in COBOL would be the most suitable technique for building an application that generates custom reports based on user input and database data. Dynamic SQL allows you to construct SQL statements dynamically at runtime, facilitating flexible and customized report generation.
In a team project, you need to create a hierarchy of classes with common attributes and behaviors. How can you implement this efficiently in Object-Oriented COBOL?
- Define a "RECORD" structure
- Implement "SEARCH ALL" operation
- Use the "CLASS" keyword
- Utilize "WORKING-STORAGE" section
To create a hierarchy of classes in Object-Oriented COBOL, you use the "CLASS" keyword. This keyword allows you to define classes with common attributes and behaviors, facilitating the creation of a class hierarchy.
What is the main purpose of error handling in COBOL programs?
- To detect and respond to unexpected situations during program execution
- To enhance program performance
- To improve program readability
- To reduce the size of the program code
Error handling in COBOL is crucial for detecting and responding to unexpected situations, such as invalid input or system errors, ensuring graceful program execution and preventing unintended consequences.
In COBOL, how can you handle multiple conditions efficiently using the "EVALUATE" statement?
- By employing the "ELSE" clause
- By specifying different conditions using "WHEN" clauses
- By using nested "IF" statements
- By utilizing the "ALSO" keyword
The "EVALUATE" statement in COBOL allows efficient handling of multiple conditions by using "WHEN" clauses. Each "WHEN" clause represents a different condition, providing a clear and structured way to handle various cases.
The COBOL intrinsic function FUNCTION ______ is commonly used for string manipulation.
- LENGTH
- REVERSE
- TRIM
- UPPER-CASE
The FUNCTION TRIM in COBOL is commonly used for string manipulation. It allows you to remove leading and trailing spaces from a string, providing a cleaner and more controlled data representation.
In COBOL, what is the primary purpose of the INVALID KEY phrase when using the READ verb?
- It indicates the end of the file
- It is a syntax error
- It is used to specify actions to be taken if an I/O operation fails
- It signifies an invalid condition in the data being read
The INVALID KEY phrase in the READ verb is used to handle situations where there is an invalid condition in the data being read. This can include data conversion errors or data integrity issues, allowing the program to take specific actions when such conditions occur.
You are working on a mission-critical COBOL application that must continue running even in the presence of non-fatal errors. Which error recovery strategy should you implement to achieve this?
- Graceful degradation
- Process termination
- Use of the PERFORM THRU statement
- Use of the STOP RUN statement
Graceful degradation is an error recovery strategy in COBOL where the application continues to run even in the presence of non-fatal errors. It involves handling errors in a way that allows the program to provide partial functionality while ensuring overall stability.
When debugging a COBOL program, what does it mean if you encounter a "syntax error"?
- A logical error in the program
- An issue with hardware
- The program is running successfully
- There is a mistake in the program's structure or language rules
Encountering a "syntax error" during COBOL debugging indicates a mistake in the program's structure or language rules. This could include incorrect usage of COBOL statements, missing periods, or other syntax-related issues that prevent the program from being compiled or executed.
When defining an OCCURS clause with a higher OCCURS DEPENDING ON clause, what is the purpose of the OCCURS VARYING phrase?
- It defines the starting index of the array
- It designates a data item whose value controls the number of occurrences
- It indicates the number of occurrences at runtime
- It specifies the size of the array elements
The OCCURS VARYING phrase is used to designate a data item whose value at runtime controls the number of occurrences of the array. This provides flexibility in managing the array size based on dynamic conditions.