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.
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.
What is the purpose of the INITIALIZE verb in COBOL?
- To declare variables in COBOL
- To initialize variables with random values
- To set all data items to their default values
- To terminate the COBOL program
The INITIALIZE verb in COBOL is used to set all data items to their default values. It is commonly used at the beginning of a program to initialize variables and data structures before processing begins.
In the COBOL Procedure Division, which statement is used for making decisions and implementing conditional logic?
- ACCEPT statement
- EVALUATE statement
- IF statement
- PERFORM statement
The EVALUATE statement in COBOL is used for making decisions and implementing conditional logic. It allows for multiple conditions to be tested, and corresponding actions to be taken based on the true condition.
In indexed file processing, the use of ____________ keys can enhance the performance of record retrieval operations.
- Alternate
- Composite
- Primary
- Secondary
In indexed file processing, secondary keys are additional keys created to enhance the performance of record retrieval operations. These keys provide alternative paths for accessing records, reducing the time and resources required for searching and retrieving specific data.
COBOL provides the _____ clause to specify the data type of elements within a table.
- DATA
- INDEX
- OCCURS
- PIC
COBOL uses the PIC (Picture) clause to specify the data type of elements within a table. It allows you to define the characteristics of the data, such as its format, size, and type.
Explain the concept of deadlock in the context of file locking in COBOL. How can it be avoided or resolved?
- Deadlock occurs when two or more processes are blocked, each waiting for the other to release a lock. To avoid deadlock, use a consistent order when acquiring locks or implement timeout mechanisms. Resolution involves detecting deadlock and releasing locks in a controlled manner.
- Option 2
- Option 3
- Option 4
Deadlock in COBOL file locking happens when processes are blocked, waiting for each other's locks. Avoiding deadlock involves careful lock acquisition order and implementing timeouts. Resolution includes detecting deadlock and releasing locks systematically.
How can you terminate a PERFORM loop in COBOL using the EVALUATE statement?
- By using the BREAK statement
- By using the EXIT PERFORM statement
- By using the WHEN OTHER condition
- By using the WHEN condition with a specific value
The EVALUATE statement in COBOL can be used to terminate a PERFORM loop by incorporating the EXIT PERFORM statement within one of the WHEN conditions. This allows the program to exit the loop based on a specified condition.