In a multi-user COBOL application, two users are attempting to update the same record in a file simultaneously. How can you prevent conflicts and ensure that only one user can update the record at a time?
- Apply transaction rollback on conflicts
- Enable file versioning
- Implement record-level locking
- Use a semaphore mechanism
To prevent conflicts when multiple users are updating the same record simultaneously, implementing record-level locking is crucial. This ensures that only one user can update the record at a time, avoiding conflicts and maintaining data consistency.
In COBOL, which operator is used for addition?
- * (Multiply)
- + (Plus)
- - (Minus)
- / (Divide)
The addition operation in COBOL is represented by the plus (+) operator. It is used to add two or more numeric values in COBOL programs.
What role does the "SORT" operation play in optimizing file handling performance in COBOL?
- It arranges data in ascending order for readability
- It helps in sorting large files for efficient processing
- It is used to concatenate multiple files
- It optimizes file storage for faster retrieval
The "SORT" operation in COBOL is used to arrange data in a specified order, facilitating efficient processing of large files by enabling easier retrieval based on the sorted key.
A group item in COBOL can contain multiple elementary items and is defined using the _________ keyword.
- FILLER
- GROUP
- OCCURS
- REDEFINES
In COBOL, a group item is defined using the GROUP keyword. It allows for the grouping of multiple elementary items under a common name for organizational and hierarchical structuring of data.
The ______ condition handler in COBOL allows you to define custom error-handling logic based on specific conditions.
- CONDITION-CONTROL
- CONDITION-HANDLER
- HANDLER-CONDITION
- HANDLING-CONDITION
The CONDITION-HANDLER in COBOL enables the programmer to define custom error-handling logic based on specific conditions. It provides a way to handle errors or exceptional situations in a tailored manner.
The _____ clause is used to declare the initial value of a COBOL constant.
- ASSIGN
- DEFAULT
- INITIAL
- VALUE
In COBOL, the VALUE clause is used to declare the initial value of a constant. It allows you to assign a value to a data item at the time of its declaration.
What are variable-length records in COBOL primarily used for?
- Efficiently storing records of fixed length
- Facilitating random access to records
- Handling varying-length data, like free-form text
- Simplifying program logic
Variable-length records in COBOL are primarily used for handling data with varying lengths, such as free-form text or variable-length fields. This flexibility allows for efficient storage of data with dynamic lengths.
In COBOL, which file organization is most suitable for direct access to records by a specific key?
- Dynamic
- Indexed
- Relative
- Sequential
Indexed file organization in COBOL is most suitable for direct access to records by a specific key. It allows for efficient retrieval based on a defined key value, enabling faster data access compared to sequential or relative file organizations.
Which COBOL file access mode is commonly used with VSAM and ISAM files when data can be both read and written?
- EXTEND
- I-O (Input-Output)
- INPUT
- OUTPUT
The I-O (Input-Output) file access mode is commonly used with VSAM and ISAM files when data can be both read and written. This mode allows for a combination of read and write operations on the file.
In a COBOL application, you are tasked with processing inventory items. Each item has a varying quantity that you need to update. Which type of PERFORM loop should you use, and how would you implement it?
- PERFORM THRU loop
- PERFORM UNTIL loop
- PERFORM VARYING loop
- PERFORM WITH TEST BEFORE loop
A PERFORM VARYING loop would be appropriate for processing inventory items with varying quantities. This loop type is useful when you need to iterate over a range of values. In this case, you can use it to iterate through the inventory items, updating the quantity for each item in the loop body.
In a COBOL program, you need to write records to a file, and you want to handle write errors gracefully. Which COBOL file control verb allows you to do this?
- CLOSE
- REWRITE
- START
- WRITE
The REWRITE verb in COBOL is used to rewrite records in a file. It is particularly useful for updating existing records in a file. When used with appropriate error handling techniques, it allows graceful handling of write errors in a COBOL program.
What is the purpose of the REDEFINES clause in COBOL?
- To define an alternate entry point in a program
- To redefine a data item with a new name
- To reorganize data items for better performance
- To share storage space between two or more data items
The REDEFINES clause in COBOL is used to share storage space between two or more data items. It allows different data items to occupy the same storage location, enabling data reusability and flexibility.