You're developing a database system and need to frequently update records. What file handling technique would you use to efficiently update specific records without reading the entire file?
- Direct File Updating
- Indexed File Updating
- Random File Updating
- Sequential File Updating
Indexed File Updating would be the most efficient technique for frequently updating specific records in a database system. With an index, the system can quickly locate and update the desired record without the need to read the entire file sequentially. This reduces the time and resources required for updates, making it a suitable choice for scenarios where frequent record updates are a common operation in a database.
In the context of searching algorithms, why might a binary search be preferred over a linear search?
- Binary search guarantees to find the target quickly
- Binary search is always faster
- Binary search requires sorted data
- Binary search works for unsorted data
Binary search is preferred when data is sorted as it allows for efficient searching, while a linear search works for unsorted data.
Why might a programmer choose to use an array of structures in a C program?
- To create global variables
- To perform text formatting
- To sort data
- To store related data efficiently
Programmers use arrays of structures to efficiently manage and organize related data.
In the context of file handling, what is the advantage of using binary files over text files?
- Data preservation
- Human readability
- Portability
- Smaller file size
One of the advantages of using binary files over text files in file handling is data preservation. Binary files store data as a sequence of bytes, preserving the exact representation of data without any character encoding or formatting. This makes them suitable for storing complex data structures and preserving data integrity.
Which of the following best describes the concept of recursion in C programming?
- A function calling itself directly or indirectly
- A loop mechanism for repeating a set of instructions
- A method to divide a problem into smaller subproblems
- A way to define constant values
Recursion in C programming involves a function calling itself either directly or indirectly. It's a technique used to solve problems by breaking them down into smaller instances, making it an essential concept in programming.
How does using pointers with arrays affect the performance of a C program?
- It always degrades performance
- It can improve performance in some cases
- It has no effect on performance
- It only affects memory usage, not performance
Using pointers with arrays in a C program can actually improve performance in some cases. By using pointers, you can manipulate array elements more efficiently and access them directly, reducing the overhead of array indexing. This can lead to better performance. However, it's essential to use pointers carefully to avoid issues like memory corruption.
The ______ stream in C is used for unbuffered error messages.
- stderr
- stdout
- printf
- ferror
The correct option is a) stderr. The stderr stream is used for unbuffered error messages in C programs.
In a large C program, you notice that a variable is being used in multiple functions but is not behaving as expected. What could be the potential issue regarding the scope of the variable?
- The variable is a global variable
- The variable is a local variable
- The variable is a static variable
- The variable is an automatic variable
The potential issue with the variable not behaving as expected could be that it is a global variable. Global variables have a larger scope and can be modified by multiple functions, which may lead to unintended changes. It's important to be cautious when using global variables in large programs. Static variables retain their values but have a limited scope, making them less likely to cause scope-related issues. Automatic and local variables are confined to individual functions and are less likely to impact other parts of the program.
The fseek function allows for ________ access of data within a file.
- random
- direct
- sequential
- indexed
The correct option is sequential. The fseek() function, when used with SEEK_SET, SEEK_CUR, or SEEK_END, allows for sequential access to data within a file. It enables you to move the file pointer forward or backward, or directly to the end of the file, facilitating sequential data access.
When defining a structure in C, memory is not allocated until an ________ of the structure is created.
- array
- function
- instance
- pointer
In C, memory for a structure is not allocated until an instance of the structure is created. An instance represents a specific object based on the structure's definition.