How can you handle file positioning errors in COBOL?

  • By checking the value of the FILE-STATUS special register
  • By using the "AT END" condition
  • By using the "INVALID KEY" phrase
  • By using the "NOT INVALID" condition
File positioning errors in COBOL can be handled by using the "INVALID KEY" phrase. This allows programmers to specify actions to be taken when there is an issue with positioning within the file, such as moving to a default record or taking corrective measures.

In COBOL, what is the default scope of a variable declared within a procedure?

  • Global scope
  • Local scope
  • Regional scope
  • Universal scope
By default, a variable declared within a procedure in COBOL has a local scope. This means that the variable is accessible only within the procedure in which it is declared, reducing the risk of unintended interference with other parts of the program.

Explain the concept of "caching" in the context of file handling performance optimization.

  • Caching is a technique to store frequently accessed data in memory for faster retrieval
  • Caching is used only for read-only file operations
  • It involves compressing file data to reduce storage space
  • It refers to creating multiple copies of files for redundancy
Caching in file handling optimization involves storing frequently accessed data in memory, reducing the need for repeated disk access. This results in faster read operations as the data is readily available in memory, improving overall system performance.

The _____ statement in COBOL is used for looping and repetition.

  • EVALUATE
  • IF
  • MOVE
  • PERFORM
The PERFORM statement in COBOL is used for looping and repetition. It allows a set of statements to be executed iteratively based on a specified condition or a fixed number of times.

When using the PERFORM statement in COBOL, what is the difference between PERFORM...THRU and PERFORM...UNTIL?

  • PERFORM...THRU is used for conditional statements, and PERFORM...UNTIL is used for unconditional statements.
  • PERFORM...THRU is used for looping, and PERFORM...UNTIL is used for sequential execution.
  • PERFORM...THRU is used with arrays, and PERFORM...UNTIL is used with strings.
  • PERFORM...THRU specifies a range of paragraphs to be executed, while PERFORM...UNTIL repeats execution until a specified condition is true.
PERFORM...THRU is used to specify a range of paragraphs to be executed sequentially, while PERFORM...UNTIL repeats the execution until a specified condition is true. Understanding the difference is crucial for effective use of the PERFORM statement in COBOL programs.

What is the key difference between "EVALUATE" and "IF" statements in COBOL?

  • "EVALUATE" is used for multiple condition testing, while "IF" is for single condition testing
  • "IF" is used for arithmetic operations, while "EVALUATE" is for logical operations
  • "IF" is used for multiple condition testing, while "EVALUATE" is for single condition testing
  • Both "EVALUATE" and "IF" are interchangeable
The key difference is that "EVALUATE" is designed for handling multiple condition tests in a more structured way, allowing for cleaner and more readable code when dealing with complex scenarios, whereas "IF" is primarily for single condition testing.

In COBOL, what is the significance of the COMPUTATIONAL USAGE clause when defining numeric data items?

  • It defines the level of the item
  • It is used for conditional processing
  • It specifies the data type of the item
  • It specifies the initial value of the item
The COMPUTATIONAL USAGE clause in COBOL is used to specify the representation and storage format of numeric data items. It defines whether the item is binary, packed decimal, or floating-point. This declaration is crucial for proper storage allocation and processing of numeric data.

Which intrinsic function is used to return the current date in COBOL?

  • FUNCTION CURRENT-DATE
  • FUNCTION DATE-CURRENT
  • FUNCTION DATE-NOW
  • FUNCTION NOW
The FUNCTION CURRENT-DATE in COBOL is used to retrieve the current date. It returns a data item containing the current date in the format YYYYMMDD.

In COBOL, the EXIT statement is commonly used in conjunction with the _________ condition.

  • EVALUATE
  • IF
  • NOT
  • WHEN
In COBOL, the EXIT statement is commonly used in conjunction with the WHEN condition. This allows the program to exit a loop or a paragraph based on a specified condition.

How does inheritance work in Object-Oriented COBOL, and what benefits does it offer?

  • By defining the size and type of data
  • By optimizing program execution
  • By organizing data in memory
  • Inheritance allows a class (subclass) to inherit attributes and behaviors from another class (superclass). Benefits include code reuse, extensibility, and the ability to model relationships between classes.
In Object-Oriented COBOL, inheritance enables a subclass to inherit properties from a superclass, promoting code reuse, extensibility, and the modeling of relationships. A subclass can reuse attributes and behaviors from its superclass, leading to more maintainable code.

You are working on a COBOL program that processes a customer database with the potential for duplicate customer IDs. How would you efficiently identify and handle duplicate customer records to ensure data accuracy?

  • Implement a hash function to identify duplicate customer IDs
  • Use a SORT and MERGE process to eliminate duplicates based on customer IDs
  • Use a sequential search to identify and remove duplicate customer records
  • Utilize a COBOL table to store unique customer IDs and compare incoming records
Using a SORT and MERGE process is an efficient way to eliminate duplicate customer records based on customer IDs, ensuring data accuracy in the customer database. It involves sorting the data based on customer IDs and merging the records to eliminate duplicates.

The _____ clause is used to specify the file organization for a COBOL file.

  • DATA DIVISION
  • ENVIRONMENT DIVISION
  • FILE-CONTROL
  • RECORDING MODE
In COBOL, the FILE-CONTROL clause is used to specify the organization of files. It includes clauses like SELECT and ASSIGN, allowing you to define the file structure and its associated external resources.