practical and interview questions - ashish-ghub/docs GitHub Wiki

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((largestAndSmallest)) public static void largestAndSmallest(int[] numbers) {

int largest = Integer.MIN_VALUE; int smallest = Integer.MAX_VALUE;
for (int number : numbers) {
    if (number > largest)
        { largest = number; } 
   else if (number < smallest) 
       { smallest = number; }
}

Producer consumer :

import java.util.LinkedList;

public class Threadexample {

public static void main(String[] args) 
    throws InterruptedException 
{ 
    // Object of a class that has both produce() 
    // and consume() methods 
    final PC pc = new PC(); 

    // Create producer thread 
    Thread t1 = new Thread(new Runnable() { 
        @Override
        public void run() 
        { 
            try { 
                pc.produce(); 
            } 
            catch (InterruptedException e) { 
                e.printStackTrace(); 
            } 
        } 
    }); 

    // Create consumer thread 
    Thread t2 = new Thread(new Runnable() { 
        @Override
        public void run() 
        { 
            try { 
                pc.consume(); 
            } 
            catch (InterruptedException e) { 
                e.printStackTrace(); 
            } 
        } 
    }); 

    // Start both threads 
    t1.start(); 
    t2.start(); 

    // t1 finishes before t2 
    t1.join(); 
    t2.join(); 
} 

// This class has a list, producer (adds items to list 
// and consumber (removes items). 
public static class PC { 

    // Create a list shared by producer and consumer 
    // Size of list is 2. 
    LinkedList<Integer> list = new LinkedList<>(); 
    int capacity = 2; 

    // Function called by producer thread 
    public void produce() throws InterruptedException 
    { 
        int value = 0; 
        while (true) { 
            synchronized (this) 
            { 
                // producer thread waits while list 
                // is full 
                while (list.size() == capacity) 
                    wait(); 

                System.out.println("Producer produced-"
                                   + value); 

                // to insert the jobs in the list 
                list.add(value++); 

                // notifies the consumer thread that 
                // now it can start consuming 
                notify(); 

                // makes the working of program easier 
                // to  understand 
                Thread.sleep(1000); 
            } 
        } 
    } 

    // Function called by consumer thread 
    public void consume() throws InterruptedException 
    { 
        while (true) { 
            synchronized (this) 
            { 
                // consumer thread waits while list 
                // is empty 
                while (list.size() == 0) 
                    wait(); 

                // to retrive the ifrst job in the list 
                int val = list.removeFirst(); 

                System.out.println("Consumer consumed-"
                                   + val); 

                // Wake up producer thread 
                notify(); 

                // and sleep 
                Thread.sleep(1000); 
            } 
        } 
    } 
}

}

.

1. query to retrieve duplicate records from a table.

SELECT EmpID, EmpFname, Department COUNT(*) FROM EmployeeInfo GROUP BY EmpID, EmpFname, Department HAVING COUNT(*) > 1;

1. Write a query to retrieve the list of employees working in the same department.

Select DISTINCT E.EmpID, E.EmpFname, E.Department FROM EmployeeInfo E, Employee E1 WHERE E.Department = E1.Department AND E.EmpID != E1.EmpID;

Q24. Write a query to retrieve the last 3 records from the EmployeeInfo table.

SELECT * FROM EmployeeInfo WHERE EmpID <=3 UNION SELECT * FROM (SELECT * FROM EmployeeInfo E ORDER BY E.EmpID DESC) AS E1 WHERE E1.EmpID <=3;

Q25. Write a query to find the third-highest salary from the EmpPosition table.

SELECT TOP 1 salary FROM( SELECT TOP 3 salary FROM employee_table ORDER BY salary DESC) AS emp ORDER BY salary ASC;

1. How to write a query to show the details of a student from Students table whose FirstName starts with ‘K’?

---

SELECT * FROM Students WHERE FirstName LIKE ‘K%’.

How to display employee records who gets more salary than the average salary in the department? This can be done by this query –

1 Select * from employee where salary>(select avg(salary) from dept, employee where dept.deptno = employee.deptno;

Employee( empid, salary, departId,) Department(departId, deparment name )