Python Programming Fundamentals

Database Fundamentals

• A database is a structured collection of data stored electronically.
• Databases are needed to manage data efficiently, making data searching, sorting, and manipulation easy.
• Common database issues include Data Redundancy, Data Isolation, Data Security, and Scalability Issues.

Database Components

• Tables represent entities and relationships.
• Fields are individual pieces of data within a table.
• Records are rows in a table representing instances of entities.
• Queries are used to retrieve specific data from tables.
• Reports provide summarized views of data.
• Forms are interfaces for data input.
• Primary Key is a unique identifier for each record in a table.
• Foreign Key creates relationships between tables.

Database Types

• Relational Databases organize data into tables that can be linked by common fields.
• Examples of Relational Databases include MySQL and Oracle.
• NoSQL Databases have flexible schemas.
• Examples of NoSQL Databases include MongoDB and Cassandra.

Security Threats

• Malware is software designed to harm or exploit any programmable device, service, or network.
• Phishing is a fraudulent attempt to obtain sensitive information by disguising oneself as a trustworthy entity.
• Man-in-Middle Attack involves eavesdropping on the communication between two parties to steal or manipulate data.

Security Principles

• Confidentiality ensures that information is accessible only to those authorized to have access.
• Integrity assures the accuracy and reliability of information and systems.
• Availability ensures that authorized users have access to information and resources when needed.

Security Best Practices

• Use strong, unique passwords for different accounts.
• Enable two-factor authentication (2FA) where possible.

Binary Code

• Binary code uses only two digits: 1 and 0, which are called bits.

Ethics

• Different ethical lenses include the right lens, the justice lens, the common good lens, the caring lens, the utilitarian lens, and the virtue lens.

Variables

• Variables are containers for storing data values.
• Rules for naming a variable include:
  • Starting with a letter or the underscore character
  • Not starting with a number
  • Containing only alpha-numeric characters and underscores
  • Being case-sensitive
  • Not being a Python keyword

Data Types

• Variables can store different data types.
• In Python, the data type for a variable is set when a value is assigned to it.

User Input

• The input() function is used to take user input.
• The input() function reads every input as a string unless it is cast into something else.

Pseudocode

• Pseudocode allows developers to plan and express algorithms in a language-independent manner before writing actual code.
• Pseudocode is written using simple language and structured like code, using statements, loops, and conditions.

Operators

• Arithmetic operators include +, -, *, / (float), // (floor), and %.
• Logical operators include And (&&), Or, and Not.
• “=” is used to assign a value to a variable, while “==” is used to check if two values are equal.

Conditional Statements

• Conditional statements are used to execute different actions based on different conditions.
• 'else' is used to execute a block of code if the conditional statement is false.
• 'elif' (short for else if) is used to check additional conditions after the initial 'if' statement.

Lists

• Lists are used to store multiple items in a single variable.
• To add something to a list, you can use the append() method or concatenation (+ operator).
• To access an item from a list, you can use square brackets ([]) with the index number.

Loops

• Loops are used to repeatedly execute a block of code.
• The range() function generates a sequence of numbers that is commonly used for looping.
• Using the range() function can be more memory efficient and provide more control over the loop iteration.

Variable Scope

• A local variable is declared inside a function and can only be accessed within that function.
• A global variable is declared outside of any function and can be accessed throughout the program.
• The scope of a variable refers to where in the code it can be accessed and manipulated.

Flowchart Symbols

• Rectangle: Represents a process or action.
• Diamond: Represents a decision or conditional statement.
• Parallelogram: Represents input or output.
• Oval: Represents the start or end of a process.

Flowchart Representation

• Conditional statements are represented by diamonds in a flow chart.
• Loops are represented by arrows looping back to a previous point in the flow chart.