You are tasked with optimizing a COBOL program that reads and processes a large sequential file. Which technique would you consider for reducing I/O operations and improving performance?
- Adding additional indexes to the file
- Implementing a buffer pool
- Increasing the block size of the file
- Using direct access instead of sequential access
Implementing a buffer pool involves buffering records in memory to reduce I/O operations when reading from or writing to the file. This can significantly improve performance by minimizing disk access and reducing overhead associated with disk I/O operations.
In a multi-user environment, what can happen if two users try to update the same record in a file simultaneously?
- Both users can successfully update the record without any issues
- Data inconsistency or corruption may occur
- The file will automatically merge the updates from both users
- The system will generate an error and prevent simultaneous updates
If two users try to update the same record in a file simultaneously without proper file locking, it can lead to data inconsistency or corruption. File locking is essential to control access and avoid conflicts in such scenarios.
When defining a group data item in COBOL, what does the REDEFINES clause allow you to do?
- Create a new data item
- Define the length of the data item
- Reuse the same memory space for different data representations
- Specify the data type of the item
The REDEFINES clause in COBOL allows you to reuse the same memory space for different data representations. This means that one data item can be defined in terms of another, sharing the same memory space, which can be useful for data conversions and optimizations.
Can a group data item contain both numeric and alphanumeric data items?
- No
- Only if explicitly specified using the PICTURE clause
- Only if explicitly specified using the USAGE clause
- Yes
Yes, a group data item in COBOL can contain both numeric and alphanumeric data items. This flexibility allows for the grouping of related data items regardless of their data types, facilitating better organization and readability of code.
The INSPECT statement in COBOL allows you to search for and _____ occurrences of specific characters or phrases in a field.
- Replace
- Delete
- Count
- Add
The INSPECT statement in COBOL is used for string manipulation. The COUNT option allows you to count the occurrences of specific characters or phrases in a given field, providing flexibility in handling character data.
The 88-level condition names in COBOL are used for creating ________ conditions based on data values.
- Boolean
- Exclusive
- Parallel
- Sequential
The 88-level condition names in COBOL are used for creating Boolean conditions based on specific data values. They provide a convenient way to express conditions in a more readable and self-explanatory manner.
The Data Division in COBOL is responsible for describing the structure and ________ of data items used in the program.
- Characteristics
- Format
- Organization
- Organization and Storage
The Data Division in COBOL describes both the structure and organization of data items. It defines how data is stored, such as the length, type, and arrangement of fields within records.
What is the purpose of the OCCURS clause in COBOL?
- To declare constants
- To define repeating data fields or arrays
- To initialize variables
- To specify file access mode
The OCCURS clause in COBOL is used to define repeating data fields or arrays. It allows the programmer to specify the number of times a particular data item or group of data items is repeated in a record or record group. This is especially useful for handling repetitive data structures like arrays.
The _______ statement in COBOL is often used to switch control to the next iteration of a loop.
- CONTINUE
- EXIT
- ITERATE
- NEXT
The ITERATE statement in COBOL is used to transfer control to the next iteration of a loop. It allows for skipping the remaining statements in the loop and proceeding with the next iteration.
In a COBOL program, you have encountered a situation where you need to exit the program due to a critical error. Which statement should you use to ensure a clean program termination?
- EXIT PARAGRAPH
- EXIT PROGRAM
- GOBACK
- STOP RUN
The STOP RUN statement in COBOL is used to terminate the program gracefully. It releases resources, closes files, and performs necessary cleanup before ending the program.