Practical26

SET–1

Q1 (a) Stack – Products

Program

# Stack program for Products

L = [("Laptop", 90000), ("Mobile", 30000), ("Pen", 50), ("Headphones", 1500)]
Products = []

def Push_element():
    for item in L:
        if item[1] > 50:
            Products.append(item)
    print("After Push:", Products)

def Pop_element():
    if len(Products) == 0:
        print("Stack Empty")
    else:
        while Products:
            print(Products.pop())
        print("Stack Empty")

def Show_stack():
    print("Current Stack:")
    for i in range(len(Products)-1,-1,-1):
        print(Products[i])

# Menu driven
while True:
    print("\n1.Push\n2.Pop\n3.Show\n4.Exit")
    ch = int(input("Enter choice: "))
    if ch == 1:
        Push_element()
    elif ch == 2:
        Pop_element()
    elif ch == 3:
        Show_stack()
    elif ch == 4:
        break
    else:
        print("Invalid choice")

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Q1 (b) Binary File – records.dat

import pickle

def write_data():
    f = open("records.dat", "wb")
    for i in range(4):
        roll = int(input("Enter roll: "))
        name = input("Enter name: ")
        address = input("Enter address: ")
        stu = {"roll": roll, "name": name, "address": address}
        pickle.dump(stu, f)
    f.close()
    print("Record saved.")

def show_data():
    try:
        f = open("records.dat", "rb")
        while True:
            data = pickle.load(f)
            print(data)
    except EOFError:
        f.close()

write_data()
show_data()

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Q2 SQL Queries (SALES Table)

I. Total quantity sold for each product whose total exceeds 12

SELECT Product, SUM(Quantity)
FROM SALES
GROUP BY Product
HAVING SUM(Quantity) > 12;

II. Sort SALES table by Product name (descending)

SELECT * FROM SALES
ORDER BY Product DESC;

III. Display distinct product names

SELECT DISTINCT Product FROM SALES;

IV. Customers whose names end with ‘e’

SELECT * FROM SALES
WHERE Customer LIKE '%e';

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SET–2

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Q1 (a) Stack – Toppers

Marks_List = [68,45,85,27,26,48,26,75,16,48]
Toppers = []

def Push_element():
    for m in Marks_List:
        if m > 65:
            Toppers.append(m)
    print("After Push:", Toppers)

def Pop_element():
    if len(Toppers) == 0:
        print("Stack Empty")
    else:
        while Toppers:
            print(Toppers.pop())
        print("Stack Empty")

def Show_stack():
    print("Current Stack:")
    for i in range(len(Toppers)-1,-1,-1):
        print(Toppers[i])

while True:
    print("\n1.Push\n2.Pop\n3.Show\n4.Exit")
    ch = int(input("Enter choice: "))
    if ch == 1:
        Push_element()
    elif ch == 2:
        Pop_element()
    elif ch == 3:
        Show_stack()
    elif ch == 4:
        break

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Q1 (b) Binary File – students.dat

import pickle

def write_data():
    f = open("students.dat", "wb")
    for i in range(4):
        roll = int(input("Enter roll: "))
        name = input("Enter name: ")
        marks = int(input("Enter marks: "))
        stu = {"roll": roll, "name": name, "marks": marks}
        pickle.dump(stu, f)
    f.close()
    print("Record saved.")

def Show_toppers():
    try:
        f = open("students.dat", "rb")
        while True:
            s = pickle.load(f)
            if s["marks"] > 50:
                print(s)
    except EOFError:
        f.close()

write_data()
Show_toppers()

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Q2 SQL Queries

I. Total quantity for each product excluding quantity < 5

SELECT Product, SUM(Quantity)
FROM SALES
GROUP BY Product
HAVING SUM(Quantity) >= 5;

II. Orders sorted by total price (descending)

SELECT * FROM Orders
ORDER BY Total_Price DESC;

III. Distinct customer names

SELECT DISTINCT Customer_Name FROM Orders;

IV. Sum of price where quantity is NULL

SELECT SUM(Price)
FROM Orders
WHERE Quantity IS NULL;

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