When using the "I-O" access mode, what operations can be performed on a file?
- Both reading and writing operations
- Neither reading nor writing operations
- Only reading operations
- Only writing operations
The "I-O" (Input-Output) access mode in COBOL allows both reading and writing operations on a file. It is used when a program needs to perform both input and output operations on the same file.
Explain the concept of "dynamic scope" in COBOL and how it affects variable visibility.
- Dynamic scope allows variables to be visible based on the program execution path
- Dynamic scope in COBOL is not supported
- Dynamic scope is related to runtime memory allocation
- Dynamic scope is used for handling errors dynamically
In COBOL, dynamic scope refers to the visibility of variables based on the program's execution path. Variables can be accessed based on the sequence of program calls during runtime, affecting their visibility and accessibility. This dynamic behavior is essential in certain program structures and scenarios.
In a COBOL program, you are required to maintain an employee database with records that can be accessed randomly. Which file access mode and organization should you select?
- Dynamic access mode, Indexed organization
- Random access mode, Indexed organization
- Random access mode, Relative organization
- Sequential access mode, Line-Sequential organization
For random access to records in a database, the Random access mode with Indexed file organization is suitable. This allows direct access based on a key value.
You are working on a COBOL program that needs to store employee records with multiple fields like name, age, and salary. Which section of the COBOL Data Division would you use to define these data items?
- FILE SECTION
- LINKAGE SECTION
- REPORT SECTION
- WORKING-STORAGE SECTION
In a COBOL program, the WORKING-STORAGE SECTION is used to define variables and data items that are needed during the execution of the program. It is suitable for storing temporary data like employee records, ensuring they are retained throughout the program's execution.
When reading variable-length records in COBOL, the "LENGTH OF" clause can be used to determine the _____ of the currently processed record.
- Length
- Number
- Occurrence
- Size
The "LENGTH OF" clause in COBOL is used to determine the length of the currently processed record when dealing with variable-length records. It helps in handling records of varying sizes during file processing.
A colleague is new to COBOL programming and asks you about the significance of the "PROGRAM-ID" paragraph in the "IDENTIFICATION DIVISION." How would you explain its role?
- It defines the data items used in the program
- It indicates the program's execution flow
- It provides a unique identifier for the COBOL program
- It specifies the input and output files for the program
The "PROGRAM-ID" paragraph in the "IDENTIFICATION DIVISION" of a COBOL program provides a unique identifier for the program. It is used to uniquely identify the COBOL program and is often referenced in other parts of the system.
When might you choose to use a PERFORM UNTIL loop instead of a PERFORM VARYING loop?
- When the loop condition is based on a fixed number of iterations
- When the loop condition is based on a logical condition at the end of the loop
- When the loop condition is based on a specific range of values
- When the loop condition is not predetermined
A PERFORM UNTIL loop in COBOL is used when the loop condition is based on a logical condition at the end of the loop. It ensures that the loop continues until a specified condition is met, providing flexibility in defining the termination criteria.
When working with indexed files in COBOL, the _______ clause is used to specify the maximum number of alternate indexes.
- ALTINDEXMAX
- ALTMAXINDEX
- INDEXMAX
- MAXINDEX
The INDEXMAX clause in COBOL is used to specify the maximum number of alternate indexes associated with a particular file. This defines the limit on the number of alternate indexes that can be defined for efficient file access.
To identify duplicate records in a COBOL file, you can use the _____ clause in the file description.
- DUPLICATES
- OCCURS
- REPEATED
- UNIQUE
The DUPLICATES clause in the file description of a COBOL program is used to identify and handle duplicate records within the file. It allows the programmer to specify the criteria for identifying duplicates based on one or more fields.
In VSAM files, what is the role of the Alternate Index (AIX)?
- Acts as a backup index for the primary index
- Facilitates sequential access only
- Organizes records in reverse order
- Provides an alternate path to the data records based on a key field
The Alternate Index (AIX) in VSAM files serves as an alternate path to access data records based on a key field other than the primary key. It allows for efficient retrieval and random access to records using a secondary key.