SENG-LIVE-010923 Phase 3 - Python

Phase Level Objectives

• Understand the principles of Python as a language including principles of object oriented programming
• Understand the characteristics of a relational database
• Perform CRUD actions on a database using SQLAlchemy & Alembic
• Design an API to handle CRUD actions
• Communicate with an API using different HTTP verbs
• Create and present a project with a React frontend and a database-backed API backend

Lecture	Notes	Videos	Starter	Solution
1. (02/21/23) Python Fundamentals	Notes	Video	Starter	Solution
2. (02/22/23) Python Data Structures	Notes	Video	Starter	Solution
3. (02/23/23) Object Oriented Programming in Python (Part 1)	Notes	Video	Starter	Solution
4. (02/24/23) Object Oriented Programming in Python (Part 2)	Notes	Video	Starter	Solution
5. (02/27/23) SQL Fundamentals & Table Relations	Notes	Video	Starter	Solution
6. (02/28/23) Object-Relational Mapping (ORM)	Notes	Video	Starter	Solution
7. (03/03/23) SQLAlchemy & Alembic	Notes	Video	Starter	Solution
8. (03/06/23) SQLAlchemy Associations	Notes	Video	Starter	Solution

1: Python Fundamentals

Lecture Goals:

• Introduce Python and phase trajectory
• Demonstrate Python package management with pip
• Demonstrate debugging in Python with shell, print, and ipdb
• Review Python data types (str, int, float, bool, None)
• Demonstrate Python conditionals and control flow
• Demonstrate Python functions
• Review Python variable scope and the global keyword
• Review Python error messages and exceptions
• Demonstrate handling errors with try: and except:

Lecture Topics:

• Python and a Short History
• Package Management with pip
• Debugging
  • print
  • ipdb
  • Python Shell
  • Errors
  • Exceptions
    • try: except:
• Python Conditionals and Control Flow
  • if...else
  • Comparison Operators
    • >: greater than
    • >=: greater than or equal to
    • <: less than
    • <=: less than or equal to
    • ==: equal to
    • !=: not equal to
  • Logical operators
    • and:
    • or:
    • not:
• Conditional Expressions
  • Ternary
• Python Functions
  • Function Definition
  • Params
  • Default Params
  • Arguments
  • Invoking
• Error Handling
  • Reading Errors
    • Syntax Errors, Logic Errors, and Exceptions
    • AssertionError
    • IndexError and KeyError
    • NameError
    • TypeError
    • try: except:

2: Python Data Structures

Lecture Goals:

• Demonstrate Sequence types (list, tuple, range)
• Review the different uses for each Sequence type
• Demonstrate standard methods for accessing, updating and deleting values in Lists
• Review Tuples
• Review Ranges
• Demonstrate Mapping types with Dictionaries
• Demonstrate standard methods for accessing, updating and deleting values in Dictionaries
• Demonstrate Set types with set() and frozenset()
• Demonstrate for and while loops
• Demonstrate list compressions

Lecture Topics:

• Sequence Types
  • List
  • Tuple
  • Range
  • Common Sequence Operators
  • List Methods
  • Tuples and Immutable vs Mutable
• Mapping Types
  • Dict
    • switch
• Set Types
  • Set
• Loops
  • for
  • while
  • List Compression
• Sequence Operators
• Sequence Functions and Methods

3: Object Oriented Programming in Python (Part 1)

Lecture Goals:

• Define Object Oriented Programming
• Explain the benefits of Object Oriented Programming
• Explain the principles of Object-Oriented Design
• Demonstrate classes
• Demonstrate instances
• Demonstrate __init__
• Demonstrate instance method
• Demonstrate the self keyword

Lecture Topics:

• Object Oriented Programming
• Benefits of Object Oriented Programming
• Principles of Object-Oriented Design
• Classes
• Instances
• Initializing with Attributes Using __init__
• Instance Methods
• Self

4: Object Oriented Programming in Python (Part 2)

Lecture Goals:

• Demonstrate Decorators
  • @decorator
• Demonstrate class attributes
  • Defining class attributes
  • Updating class attributes
• Demonstrate class methods
  • Defining class methods
  • @classmethod
  • cls keyword
• Object Inheritance

Lecture Topics:

• Decorators
• Class Attributes
• Class Methods
• Object Inheritance

5: SQL Fundamentals & Table Relations

Lecture Goals:

• Explain why we use databases
• Explain what SQL is and why we use it
• Explain the differences between a database, server, and API
• Explain the differences between rows and columns in a table
• Explain the differences between a Foreign Key and a Primary Key
• Explain what a join table is
• Explain what it means to seed a database
• Observe using SQL to communicate with a database
• Explain what an ORM is

Lecture Topics:

• The Use Value of Databases in Applications
• Domain Modeling
• Join Table
• Mapping Columns and Rows to Classes and Instances
• Primary Keys
• Foreign Keys
• SQL
• ORM

6: Object-Relational Mapping (ORM)

Lecture Goals:

• Demonstrate configuring an application to connect with sqlite3
• Demonstrate a create table method
• Review preventative measures for SQL injection
• Demonstrate save and create methods
  • Save => Persist created instance to DB
  • Create => Instantiate / persist created instance to DB, return new instance
• Demonstrate query methods to find and retrieve resources

Lecture Topics:

• The benefits of ORM
• Connecting ORMs to DBs
• How to Use Data From a Database to Make Python Objects
• Mapping a Database Table to a Python Object
• Turning Database Rows into Python Objects

7: SQLAlchemy & Alembic

Lecture Goals:

• Explain what SQLAlchemy is and how it benefits us as an ORM
  • Demonstrate creating a database with SQLAlchemy
  • Demonstrate creating a schema
  • Demonstrate creating columns with SQLAlchemy
  • Demonstrate creating column constraints with SQLAlchemy
  • Demonstrate creating indexes with SQLAlchemy
  • Demonstrate creating default values
• Explain Alembic and what it does for us
  • Demonstrate configuring an application to use Alembic
  • Demonstrate creating migrations using Alembic
  • Demonstrate creating manual migrations using Alembic
  • Demonstrate CRUD in SQLAlcehmy
    • Adding data with .commit
      • .all, .order_by, desc, limit, function filter, and loop compression to grab specific columns
    • Querying data with .query
    • Updating data with .update and .commit
    • Deleting data with .delete

Lecture Topics:

• Creating a Database
• Creating a Schema
  • Columns
  • Constraints
  • Index
  • Default Values
• Alembic
  • Migrations
    • Configuring the Migration Environment
    • Creating Migrations
    • Manual Migrations
• CRUD
  • Sessions
  • Transactions
  • __repr__
  • Creating Records
    • Seeding Data
  • Reading Records
    • Selecting Specific Columns
    • Ordering
    • Limits
    • Filtering
    • Func
  • Updating Data
  • Deleting Data

8: SQLAlchemy Associations

Lecture Goals:

• Review relationships, Primary keys, and Foreign keys
• Demonstrate creating a table with a Foreign key and referencing another table using relationship() and backref()
• Demonstrate using Alembic to generate tables with relationships
• Demonstrate querying methods to view table relationships
• Demonstrate a “one to many” association
• Demonstrate a “many to many” association with a join model

Lecture Topics:

• Design Database Tables
• One-to-Many
• Foreign Key Columns
• relationship() and backref()
• One-to-One
• Alembic Migrations to Generate Table Relationships
• Relation Query Methods
• Many-to-Many