In the COBOL Procedure Division, which statement is used for making decisions and implementing conditional logic?
- ACCEPT statement
- EVALUATE statement
- IF statement
- PERFORM statement
The EVALUATE statement in COBOL is used for making decisions and implementing conditional logic. It allows for multiple conditions to be tested, and corresponding actions to be taken based on the true condition.
In indexed file processing, the use of ____________ keys can enhance the performance of record retrieval operations.
- Alternate
- Composite
- Primary
- Secondary
In indexed file processing, secondary keys are additional keys created to enhance the performance of record retrieval operations. These keys provide alternative paths for accessing records, reducing the time and resources required for searching and retrieving specific data.
COBOL provides the _____ clause to specify the data type of elements within a table.
- DATA
- INDEX
- OCCURS
- PIC
COBOL uses the PIC (Picture) clause to specify the data type of elements within a table. It allows you to define the characteristics of the data, such as its format, size, and type.
Explain the concept of deadlock in the context of file locking in COBOL. How can it be avoided or resolved?
- Deadlock occurs when two or more processes are blocked, each waiting for the other to release a lock. To avoid deadlock, use a consistent order when acquiring locks or implement timeout mechanisms. Resolution involves detecting deadlock and releasing locks in a controlled manner.
- Option 2
- Option 3
- Option 4
Deadlock in COBOL file locking happens when processes are blocked, waiting for each other's locks. Avoiding deadlock involves careful lock acquisition order and implementing timeouts. Resolution includes detecting deadlock and releasing locks systematically.
When an error occurs in a COBOL program, what is the role of the "EXIT" statement?
- To display an error message to the user
- To jump to a specific paragraph and continue execution
- To skip the next statement and continue execution
- To terminate the program immediately
The "EXIT" statement in COBOL is used to jump to a specific paragraph when an error occurs, allowing for customized error handling and graceful termination of the program. It provides a way to manage errors and control the program flow based on specific conditions.
You are developing a COBOL program to process a file with variable-length records that represent customer orders. Each record has a different length based on the number of items ordered. What clause should you use to efficiently read and process these records?
- DEPENDING ON
- LINAGE IS 66
- OCCURS
- RECORDING MODE IS V
In COBOL, the DEPENDING ON clause is used to handle variable-length records. It allows the program to dynamically determine the length of the record based on the value specified in another field, such as the number of items ordered in this scenario.
What keyword is used to invoke a subprogram from within the main program?
- CALL
- INVOKE
- PERFORM
- SUBROUTINE
The CALL keyword is used in COBOL to invoke a subprogram from within the main program. It facilitates the transfer of control to the specified subprogram, which performs a specific task and returns control to the main program afterward.
The OCCURS clause in COBOL is primarily used to define ____________.
- A repeating group of data items
- A single data item
- A subroutine
- An index
The OCCURS clause in COBOL is used to define a repeating group of data items. It allows you to create arrays or tables where a data item occurs multiple times.
Explain the difference between a primary key and an alternate key in indexed file processing.
- Primary key allows duplicate values, while alternate key enforces uniqueness.
- Primary key is the default key, and alternate key is used for backup purposes.
- Primary key is used for sorting records in ascending order. Alternate key is the main key used for retrieval.
- Primary key uniquely identifies records and determines the file's physical order. Alternate key provides an alternative access path and can have duplicates.
In indexed file processing, a primary key uniquely identifies records and establishes the file's physical order. An alternate key provides an alternative access path without affecting the physical order and can have duplicate values.
How does the "WORKING-STORAGE SECTION" differ from the "LINKAGE SECTION" in COBOL?
- Working-Storage is used for data validation, while Linkage is used for data transformation
- Working-Storage is used for global variables, while Linkage is used for local variables
- Working-Storage is used for input data, while Linkage is used for output data
- Working-Storage is used for temporary storage within the program, while Linkage is used for communication between programs
The "WORKING-STORAGE SECTION" in COBOL is used for declaring variables that are used for temporary storage within the program. In contrast, the "LINKAGE SECTION" is used for communication between programs, passing data from one program to another.