How does the COBOL Procedure Division handle file I/O operations?
- COBOL does not support file I/O operations
- COBOL handles file I/O operations using the OPEN, READ, WRITE, and CLOSE statements in the Procedure Division
- COBOL uses a dedicated FILE CONTROL paragraph for file handling
- COBOL uses a separate FILE I/O Division for handling file operations
The COBOL Procedure Division handles file I/O operations using statements like OPEN, READ, WRITE, and CLOSE. These statements allow the programmer to interact with files, reading and writing data as needed within the procedural logic of the program.
When working with an OCCURS clause in COBOL, what does the INDEXED BY phrase allow you to do?
- Associate an index with an OCCURS clause to reference individual occurrences
- Define the initial value of an OCCURS clause
- Determine the data type of the OCCURS clause
- Specify the maximum number of occurrences in an OCCURS clause
The INDEXED BY phrase in COBOL allows you to associate an index with an OCCURS clause. This index can be used to reference individual occurrences within the array, enabling efficient access and manipulation of data.
When using the ENTRY statement in COBOL, variables declared in the called program have a _____ scope.
- COMMON
- GLOBAL
- LOCAL
- SHARED
When using the ENTRY statement in COBOL, variables declared in the called program have a LOCAL scope. This means that they are local to the called program and are not accessible from the calling program or other programs.
In COBOL, how is the REDEFINES clause used to redefine data items?
- By assigning a new value to the redefined item
- By changing the data type of the redefined item
- By specifying a new name for the data item being redefined
- By specifying a new size for the redefined item
In COBOL, the REDEFINES clause is used by specifying a new name for the data item being redefined. This allows the new name to share the storage space of the original data item.
What are some advantages of using relative file processing over sequential file processing in COBOL?
- Dynamic sorting of records, automatic key generation, enhanced security features
- Faster record access, ability to insert and delete records randomly, supports direct access to records
- Sequential access with no random access, limited storage usage, suitable for small datasets
- Simple and easy to implement, lower storage requirements, suitable for large datasets
Relative file processing in COBOL offers advantages such as faster record access, the ability to insert and delete records randomly, and support for direct access to records based on relative record numbers. This makes it efficient for certain types of applications compared to sequential file processing.
To minimize disk I/O in COBOL, it's essential to use ____________ techniques for file access.
- Direct
- Indexed
- Relative
- Sequential
Indexed file access techniques in COBOL involve using indexes to locate and retrieve records directly, reducing the need for sequential searches. This minimizes disk I/O by providing a more efficient way to access specific records without scanning the entire file sequentially.
In COBOL, what mechanisms or techniques can be employed to optimize file locking strategies for high-performance multi-user systems?
- Implementing complex locking algorithms without considering transaction boundaries
- Implementing record-level locking, choosing appropriate lock modes, and using transaction management to minimize lock duration
- Locking only during write operations and not during read operations
- Using file-level locking for simplicity, avoiding locking altogether, relying on database management system locks
To optimize file locking in COBOL for high-performance multi-user systems, employ mechanisms like record-level locking, choose suitable lock modes, and use transaction management to minimize lock duration. This ensures efficient concurrency while maintaining data integrity.
The OCCURS clause in COBOL is used for defining ________ in the Data Division.
- Array elements
- External procedures
- Index variables
- Record layouts
The OCCURS clause in COBOL is used for defining arrays, allowing you to specify the number of occurrences of a data item within a group. It is particularly useful for handling repetitive data structures like arrays in other programming languages.
When should you use the OCCURS clause in defining data structures?
- To allocate space for a data item
- To create a loop for processing a group of related data items
- To define a record layout for a file
- To specify the hierarchy of a data item
The OCCURS clause in COBOL is used to create a loop for processing a group of related data items. It allows the repetition of a data item or a group of data items, facilitating the handling of arrays and tables in COBOL programs.
The "PROCEDURE DIVISION" contains the actual _____ of a COBOL program.
- Data declaration
- Execution logic
- File definition
- Identification Division
The "PROCEDURE DIVISION" in COBOL holds the actual execution logic of the program. It includes statements and procedures that dictate the flow of the program and specify the operations to be performed.