student_database_with_python.py

#!/usr/bin/python3

# Import statements for libraries
import time
import MySQLdb


# Variable placeholders
Done = False

def new_student():
    # Function for getting inputs from user for new student
    roll_no=int(input("Enter New Roll No : "))
    name = input("Enter New Student Name : ")
    marks = int(input("Enter Marks : "))
    return (roll_no, name, marks)


def user_input():
    # Function to print a user menu
    print ('\n\n')
    print (30 * '-')
    print ("  M A I N - M E N U")
    print (30 * '-')

    print ('1. List Students')
    print ('2. Add Student')
    print ('3. Modify Student')
    print ('4. Remove Student')
    print ('x. Exit')
    print (30 * '-')

    #print('Enter You Choice')
    choice = input('Enter Selection [1-4, x] : ')
    print ("You entered", choice)
    return choice


if __name__=='__main__':

    # Create a connection to the database
    db = MySQLdb.connect("localhost", "etec224", "password", "exampledb")
    curs=db.cursor()

    # Loop till user decides to exit
    while Done != True:
	# Get User input and save to the variable selection
        selection = user_input()

        if selection == 'x':
            Done = True

        else:
            try:
                selection = int(selection)
            except:
                print('Invalid input')

            if selection == 1:

                print('Listing Student')

                try:

                    curs.execute("""SELECT * from STUDENT""")
                    for data in curs.fetchall():
                        print (str(data[0]) + "\t" + str(data[1]) + "\t" + str(data[2]))
                    db.commit()

                except:
                    print("Error running query")
                    db.rollback()

            elif selection == 2:
                print('Adding Student')

                try:
                    data_tuple = new_student()
                    curs.execute("""INSERT INTO STUDENT (ROLLNO, NAME, TOTAL_MARKS) VALUES(%s, %s, %s)""", data_tuple)
                    db.commit()

                except:
                    print("Error running Query")
                    db.rollback()

            elif selection == 3:
                print('Modifying student')
                try:
                    rn = input("Roll No of Student to edit : ")
                    marks = input("Enter New Marks : ")
                    curs.execute("""UPDATE STUDENT SET TOTAL_MARKS=%s WHERE ROLLNO=%s""", (marks, rn))
                    db.commit()
                except:
                    print('Error running UPDATE Query')
                    db.rollback()
            elif selection == 4:
                print('Deleting Student')
                try:
                    rn = input("Enter Roll No to delete : ")
                    curs.execute("""DELETE FROM STUDENT WHERE ROLLNO=%s """, (rn))
                    db.commit()
                except:
                    print("Error Running DELETE query.")
                    db.rollback()
            else:
                print('Unrecognized Option. Try Again.')
        time.sleep(2)