4. Be able to save a FriendsDB to a file. Add a method save() to the FriendsDB class, which takes a filename as an argument and saves all of the friends in the database to the specified filename. The file will contain one line per friend in the database, and each line of the file will contain that friend's name, followed by a tab, followed by their height, a tab, and then each of their favorite foods (separated by tabs), and finally a newline character. So for example a FriendsDB file with two friends, bimmy (height 60, favorite foods "falafel" and "vegemite") and eliza (height 170, no favorite foods) would contain lines equivalent to the following two strings. "bimmy\t60\tfalafel\tvegemite\n". "eliza\t170\t\n"

4. Be able to save a FriendsDB to a file. Add a method save() to the FriendsDB class, which takes a filename as an argument and saves all of the friends in the database to the specified filename. The file will contain one line per friend in the database, and each line of the file will contain that friend's name, followed by a tab, followed by their height, a tab, and then each of their favorite foods (separated by tabs), and finally a newline character. So for example a FriendsDB file with two friends, bimmy (height 60, favorite foods "falafel" and "vegemite") and eliza (height 170, no favorite foods) would contain lines equivalent to the following two strings. "bimmy\t60\tfalafel\tvegemite\n". "eliza\t170\t\n"

Database System Concepts

7th Edition

ISBN:9780078022159

Author:Abraham Silberschatz Professor, Henry F. Korth, S. Sudarshan

Publisher:Abraham Silberschatz Professor, Henry F. Korth, S. Sudarshan

Chapter1: Introduction

Section: Chapter Questions

Problem 1PE

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2. Make a FriendsDB class that contains a list of Friend objects. The FriendsDB should be empty be default, but it will have an add_friend method that takes a Friend object and adds them to a list of friends (which should be a field on the FriendsDB object, called self.friends). Sample usage should look like: >>> friend_db FriendsDB() >>> friend1 Friend("sarah", 165) >>> friend1.add_favorite_food("strawberries") >>> friend1.add_favorite_food("apple pie") >>> friend_db.add_friend(friend1) >>> friend_db.friends[0] is friend1 True
We will use the file classlist.txt. Note that it contains a list of usernames. 3. Write a script called finduser that is to be called as follows, where classlist is the name of the classlist file, and username is a particular student's username, either first name or last time. ./finduser classlist username The script should check that the correct number of arguments was received and print an error message if not, check whether the classlist file exists and print an error message if not, print the line of the given username in the classlist file If you have not been doing so all along, you should now add some comments to your script and thoroughly test it! 4. Write the script into your lab report.
Write a program that generates student records in a database file. Your program should be able to generate at least 10 records. The format in the database should be: student name, student id The first student id should be 20180001, second id will be 20180001 and so forth. Show screenshot of script
Write a program that connects to a database, creates a Moviestable (if it does not already exist), and provides the user the ability to manage a movie listing database. The database shouldinclude fields for a movie’s name, run-time, rating code, date ofrelease, and two primary stars. The user should be able to enternew movie information, delete existing movies, and obtain a listof movies in the database.
In this project you will implement a student database using JavaFX. A GUI should be used as the program's interface. This program must consist of two classes. (1) The first class should define the GUI and handle the database interactions: a. Combo box should allow the user to select one of the four database actions (Insert, Delete, Find, and Update). b. The database should be implemented as a HashMap, with the ID field as the key and a student record consisting of a name and major as the value. c. The operation should be performed when the user clicks the Process Request button. d. If the user attempts to insert a key that is already in the database an error message should be displayed using a JOptionPane message dialog box. e. If the user attempts to delete, find or update a record that is not in the database, a message should also be displayed. f. After each successful operation is completed a JOptionPane window should be…
Include an inner listener class to handle the events from the Save Record button. WhenSave Record button is clicked, new customer record is inserted into the table named“CUSTOMER” and display a message “New Customer Record Inserted” in a dialog box.Include another anonymous inner listener class to handle the events from the Reset button.When Reset is clicked then clear all the text fields and place the cursor in the first text fieldto allow the user to re-enter the correct values and Write a code that includes an exception handler that deals with duplicate records (e.g. sameCustomer ID.) and database error (e.g. Error establishing a database connection).
How to code this assignment JSON objects. Hint: Work on the methods in the order they are found in the documentation below. def swap_value(file_path: str, key: str, replacement): """ This function will be given a file path and a key. The file that the file path points to contains a json object. This function should, load the data in the file. Then replace the value associated with the key with replacement value. Then it should overwrite the current data in the file with the new changes. Finally it should return the old value. :param file_path: A path to file :param key: A key value in the JSON object saved in the file :param replacement: The new value that the key will be mapped to :return: The old value that the key used to be mapped to """ def update_transactions(file_path: str, transaction_list: list): """ You are part of a team tasked to create an application that helps bankers by saving their transactions for them. Your job…
Write a program that generates student records in a database file. Your program should be able to generate at least 10 records. The format in the database should be: student name, student id The first student id should be 20180001, second id will be 20180001 and so forth.
Design a Client class that interfaces with your SQLDatabase Server (from the class Server). The Client sends a SQLQuery to the SQLDatabase and receives a Dataframe from the SQLDatabase. Your class should contain the default __dunders__ and potentially introduce some custom __dunders__. classServer.py (Just change if this file has something doesn't run or doesn't fit with new code) import sqlite3import pandas as pdclass Server:def __init__(self, db_name):self.db = sqlite3.connect(db_name)self.cursor = self.db.cursor()def __enter__(self):return selfdef __exit__(self, exc_type, exc_val, exc_tb):self.db.close()def create_table(self, table_schema):self.cursor.execute(table_schema)self.db.commit()def insert_data(self, table_name, data):for i in range(len(data)):keys = ", ".join(data.columns)values = ", ".join([f"'{value}'" if pd.isna(value) else str(value) for value in data.iloc[i]])self.cursor.execute(f"INSERT INTO {table_name} ({keys}) VALUES ({values})")self.db.commit()def…
Implement all the functions from the Question 2 and make a login and sign up module, all thedata will be stored in the files and as well as in the linked list, Program will have two modules1. login2. sign upSign Up:In this module the program will ask the user to enter username, password, address, city, phonenumber, gender and will store the data in the linked list. If the username already exists in thelinked list it will ask the user to change the username, all the data will also be stored in the textfile.Login: In this module the user will enter its username and password, the program will check if the dataexists in the linked list, if yes then show “Welcome to home screen”, if not then ask the user toenter the username and password again.Work Flow:1. The program will start and all the data from the files will be loaded in the linked list.2. The login and sign up screen will pop up3. Apply proper checks, if the file exists or not (Hint: you can use try catch to handle theexceptions)…
You need to design this class. It’ll hold all the FoodWastageRecord objects in memory (notice the has-a relationship between the FoodWastageTracker class and FoodWastageRecord class in the diagram above). It’ll allow the user to Add a FoodWastageRecord to the list of records in memory. IT SHOULD NOT add duplicate records. Return true if the record was added successfully, else return false. Delete a FoodWastageRecord from memory. Return true if the record was actually deleted. Return false if the record to be deleted wasn’t found. [NOTE: This is an extra credit requirement.] Get all FoodWastageRecord objects from memory Generate and return the FoodWastageReport All four of these will be the member functions of your class. food_wastage_tracker.hpp class FoodWastageTracker { public: bool AddRecord(const FoodWastageRecord &record); bool DeleteRecord(const FoodWastageRecord &record); const std::vector<FoodWastageRecord> &GetRecords() const; FoodWastageReport…
Create a controller class, "PrintSequence" that will generate a view according to the descriptions provided in each methods. Then, in your newly created controller create 3 different methods, namely : 1.) MarioFlagPole - Accepts 1 argument, which is the Flag Pole Size. - The segment that handles your argument should only accept numbers.