Answer: (B) Issue an alter system switch logfile command.
Explanation:
When the database is in the archive log mode then, the issue in the alter system switch logfile command force the particular switch. It basically produce achieve redo log which is smaller in the size by the dedicated size of the parameter log buffer.
It also govern the particular size of the RAM (Random access memory) buffer by redo log. This command is basically faster to return in the program by the use of redo log.
On the other hand, all the options are incorrect as this command only alter the system and does not alter the database. Therefore, Option (B) is correct.
Answer:
The answer to this question can be given as:
Class definition:
public class Averager //define class Average.
{
private int sum = 0;
//define variable sum.
private int count = 0;
//define variable count.
public int getSum() //define function getSum().
{
return sum; //return value.
}
public void add(int x)
//define function add().
{
sum = sum + x; //calculate sum
count=count+1; //increase value of count.
}
public int add(int x)
//define function add().
{
return count; //return value.
}
public double getAverage() //define function getAverage().
{
return (double)sum/count; //return value
}
}
Explanation:
The above class definition can be described as:
- In the above class definition first we define a class that is " Averager". In this class we define two integer variable that is "sum and count" and assign a value that is 0. Then we define a functions :
- First we define getSum() function in this function we does not pass any value and the return type of this function is int that will return an integer value.
- Then we define add() function we use this function two times but both functions have different from each other.
- In first time implementation, we define this function and the return type of this function is void which means it does not return any value. In this function, we calculate the sum value and increase the value of the count variable by 1.
- In second time implementation, we define this function and the return type of this function is int which means it will return a value. In this function, we will return the count variable value.
- At the last, we define a getAverage() that calculates the average of the added values in the sum variable and returns its value.
Disk access is way slower than
memory access. Caching is a technique to improve the disk access time. Block cache is a caching technique which
reduces disk accesses time. Here a
portion of disk is bought to cache for reading and a modified blocks are first
changed in cache but reflected in the disk at one go. On the other hand with write through caching
each modified block is written to cache and at the same time it is written to
the disk. Write- through caching
requires more disk I/O so they can have a negative effect on the performance.
Answer:
Cleaning inside the computer
Defragmenting the hard drive
Deleting temporary files
Organizing data
Explanation:
