Author: Jorge Saldivar

June 14, 2024

In JavaScript, what is the difference between `.contains()` and `.includes()`?
In JavaScript, .contains() and .includes() are used for different purposes:

.contains(): This is a method of the Node interface in the Document Object Model (DOM). It’s used to check whether a node is a descendant of a given node, i.e., child, grandchild, etc.
```
node.contains(otherNode)
```
.includes(): This is a method of the Array and String prototypes in JavaScript. It’s used to determine whether an array includes a certain value among its entries or whether a string includes a certain substring.

For arrays:
```
array.includes(valueToFind, fromIndex)
```
For strings:
```
string.includes(searchString, position)
```
So, the main difference is that .contains() is used with DOM nodes, while .includes() is used with arrays and strings.
June 5, 2024

VS Code, Associate Jinja with HTML
Using VS Code, go to your settings.json file and add the following within the {} brackets.
```
"files.associations": {
    "*.jinja": "html",
    "*.jinja2": "html",
    "*.j2": "html",
    "*.njk": "html"
}
```
Have you tried this approach or something similar? Leave a comment if this helped or if you have another approach.

May 27, 2024

Difference between String Concatenation and String Interpolation in Python

# String Concatenation
name = "John"
age = 25
print("Hello, my name is " + name + " and I am " + str(age) + " years old.")

# String Interpolation
name = "John"
age = 25
print(f"Hello, my name is {name} and I am {age} years old.")

# String Interpolation with format()
name = "John"
age = 25
print("Hello, my name is {} and I am {} years old.".format(name, age))

# String Interpolation with format() and positional arguments
name = "John"
age = 25
print("Hello, my name is {0} and I am {1} years old.".format(name, age))

# String Interpolation with format() and keyword arguments
name = "John"
age = 25
print("Hello, my name is {name} and I am {age} years old.".format(name=name, age=age))

# String Interpolation with format() and mixed arguments
name = "John"
age = 25
print("Hello, my name is {0} and I am {age} years old.".format(name, age=age))

May 25, 2024

`for` loops in Python

# for loops
# About for loops
# for loops are used to iterate over a sequence (list, tuple, string) or other 
# iterable objects.

# Syntax
# for variable in sequence:
#    code block
# Examples

# Iterate over a list
# A list is a collection which is ordered and changeable.
print("\nIterate over a list")
fruits = ["apple", "banana", "cherry"]
for fruit in fruits:
    print(fruit)
    # Output
    # apple
    # banana
    # cherry

# Iterate over a string
# A string is a sequence of characters
print("\nIterate over a string")
for letter in "apple":
    print(letter)
    # Output
    # a
    # p
    # p
    # l
    # e

# Iterate over a range
# A range is a sequence of numbers, starting from 0 by default, and increments
print("\nIterate over a range")
for i in range(5):
    print(i)
    # Output
    # 0
    # 1
    # 2
    # 3
    # 4
    # Note: The range() function returns a sequence of numbers, starting from 0 
    # by default, and increments by 1 (by default), and stops before a 
    # specified number.

# Iterate over a tuple
# A tuple is a collection which is ordered and unchangeable.
print("\nIterate over a tuple")
colors = ("red", "green", "blue")
for color in colors:
    print(color)
    # Output
    # red
    # green
    # blue

# Iterate over a dictionary
# A dictionary is a collection which is unordered, changeable and indexed.
print("\nIterate over a dictionary")
person = {
    "name": "Alice",
    "age": 25,
    "is_active": True
}
for key in person:
    print(key, person[key])
    # Output
    # name Alice
    # age 25
    # is_active True
    # Note: The for loop iterates over the keys of the dictionary.

# Iterate over a dictionary using items() method
# The items() method returns a view object that displays a list of a given
# dictionary's key-value tuple pair.
print("\nIterate over a dictionary using items() method")
for key, value in person.items():
    print(key, value)
    # Output
    # name Alice
    # age 25
    # is_active True
    # Note: The for loop iterates over the key-value pairs of the dictionary.
    if key == "age" and value >= 18:
        print(person["name"], "is an adult.")

# Iterate over a dictionary using values() method
# The values() method returns a view object that displays a list of all the
# values in the dictionary.
print("\nIterate over a dictionary using values() method")
for value in person.values():
    print(value)
    # Output
    # Alice
    # 25
    # True
    # Note: The for loop iterates over the values of the dictionary.

# Iterate over a dictionary using keys() method
# The keys() method returns a view object that displays a list of all the keys
# in the dictionary.
print("\nIterate over a dictionary using keys() method")
for key in person.keys():
    print(key)
    # Output
    # name
    # age
    # is_active
    # Note: The for loop iterates over the keys of the dictionary.

# Iterate over a dictionary using get() method
# The get() method returns the value of the specified key.
print("\nIterate over a dictionary using get() method")
print(person.get("name"))

# Nested for loops

# clients
clients = [
    {"name": "Alice", "age": 25},
    {"name": "Bob", "age": 30},
    {"name": "Charlie", "age": 35}
]
# products
products = ["apple", "banana", "cherry"]
inventory = {
    "apple": 10,
    "banana": 20,
    "cherry": 30
}
# orders
orders = [
    {"client": "Alice", "product": "apple"},
    {"client": "Bob", "product": "banana"},
    {"client": "Charlie", "product": "cherry"}
]

# Iterate over clients
print("\nIterate over clients")
for client in clients:
    print(client["name"], client["age"])
    # Output
    # Alice 25
    # Bob 30
    # Charlie 35

# Iterate over products
print("\nIterate over products")
for product in products:
    print(product)
    # Output
    # apple
    # banana
    # cherry

# Iterate over orders
print("\nIterate over orders")
for order in orders:
    print(order["client"], order["product"])
    # Output
    # Alice apple
    # Bob banana
    # Charlie cherry

# Iterate over orders and products and update inventory
print("\nIterate over orders and products and update inventory")
for order in orders:
    for product in products:
        if order["product"] == product:
            inventory[product] -= 1
            print(order["client"], "ordered", order["product"])
            print("Inventory of", product, "is", inventory[product])
            # Output
            # Alice ordered apple
            # Inventory of apple is 9
            # Bob ordered banana
            # Inventory of banana is 19
            # Charlie ordered cherry
            # Inventory of cherry is 29
# Note: The nested for loop iterates over the orders and products and updates
# the inventory of the products.

April 23, 2024

MySQL Query Cheat Sheet

-- Create a new database
-- This creates a new database named "sandbox". This is not necessary if you already have a database to work with.
CREATE DATABASE database_name;

-- Use a specific database
-- This selects the "sandbox" database for use. Replace "sandbox" with the name of the database you want to use.
USE database_name;

-- Create a new table
-- This creates a new table named "table_name" with columns "column1" and "column2" of data types "datatype1" and "datatype2" respectively. Replace "table_name", "column1", "column2", "datatype1", and "datatype2" with the desired names and data types.
CREATE TABLE table_name (
    column1 datatype,
    column2 datatype,
    ...
);

-- Insert data into a table
-- This inserts a new row into the "table_name" table with values "value1" and "value2" for columns "column1" and "column2" respectively. Replace "table_name", "column1", "column2", "value1", and "value2" with the desired table name, column names, and values.
INSERT INTO table_name (column1, column2, ...)
VALUES (value1, value2, ...);

-- Select all rows from a table
-- This selects all rows from the "table_name" table. Replace "table_name" with the name of the table you want to select from.
SELECT * FROM table_name;

-- Select specific columns from a table
-- This selects specific columns "column1" and "column2" from the "table_name" table. Replace "column1", "column2", and "table_name" with the desired column names and table name.
SELECT column1, column2, ... FROM table_name;

-- Filter rows using WHERE clause
-- This selects all rows from the "table_name" table where the condition is met. Replace "table_name" with the name of the table you want to select from and "condition" with the desired condition.
SELECT * FROM table_name WHERE condition;

-- Update data in a table
-- This updates the "column1" and "column2" columns in the "table_name" table with new values "value1" and "value2" where the condition is met. Replace "table_name", "column1", "column2", "value1", "value2", and "condition" with the desired table name, column names, values, and condition.
UPDATE table_name SET column1 = value1, column2 = value2, ... WHERE condition;

-- Delete data from a table
-- This deletes rows from the "table_name" table where the condition is met. Replace "table_name" with the name of the table you want to delete from and "condition" with the desired condition.
DELETE FROM table_name WHERE condition;

-- Join two or more tables
-- This joins the "table1" and "table2" tables on the "column" column. Replace "table1", "table2", and "column" with the names of the tables and column you want to join on.
SELECT * FROM table1 JOIN table2 ON table1.column = table2.column;

-- Order rows in ascending or descending order
-- This selects all rows from the "table_name" table and orders them in ascending or descending order based on the "column" column. Replace "table_name" and "column" with the name of the table and column you want to order by, and "ASC" or "DESC" with the desired order.
SELECT * FROM table_name ORDER BY column ASC/DESC;

-- Limit the number of rows returned
-- This selects the first "number" rows from the "table_name" table. Replace "table_name" with the name of the table you want to select from and "number" with the desired number of rows.
SELECT * FROM table_name LIMIT number;

-- Group rows and perform aggregate functions
-- This groups rows in the "table_name" table by the "column" column and counts the number of rows in each group. Replace "table_name" and "column" with the name of the table and column you want to group by.
SELECT column, COUNT(*) FROM table_name GROUP BY column;

-- Create an index on a table
-- This creates an index named "index_name" on the "column" column in the "table_name" table. Replace "index_name", "table_name", and "column" with the desired index name, table name, and column.
CREATE INDEX index_name ON table_name (column);

-- Drop a table
-- This drops the "table_name" table. Replace "table_name" with the name of the table you want to drop. This is a destructive operation and cannot be undone.
DROP TABLE table_name;

-- Drop a database
-- This drops the "database_name" database. Replace "database_name" with the name of the database you want to drop. This is a destructive operation and cannot be undone.
DROP DATABASE database_name;

-- Show all databases
SHOW DATABASES;

-- Show all tables in a database
SHOW TABLES;

-- Show the structure of a table
-- This shows the columns, data types, and other information about the "table_name" table. Replace "table_name" with the name of the table you want to show the structure of.
DESC table_name;

-- Show the indexes on a table
-- This shows the indexes on the "table_name" table. Replace "table_name" with the name of the table you want to show the indexes of.
SHOW INDEX FROM table_name;

-- Show the status of the server
-- This shows various status information about the server, such as the number of connections, queries, and other statistics.
SHOW STATUS;

-- Show the current user
SELECT USER();

-- Show the current database
SELECT DATABASE();

-- Show the version of MySQL
SELECT VERSION();

-- Show the current date and time
SELECT NOW();

-- Show the current time zone
SELECT @@time_zone;

-- Join two or more tables
-- This joins the "table1" and "table2" tables on the "column" column.
-- A join combines rows from two or more tables based on a related column between them.
SELECT * FROM table1 JOIN table2 ON table1.column = table2.column;

-- Left join two or more tables
-- This left joins the "table1" and "table2" tables on the "column" column.
-- A left join returns all rows from the left table and the matched rows from the right table.
SELECT * FROM table1 LEFT JOIN table2 ON table1.column = table2.column;

-- Right join two or more tables
-- This right joins the "table1" and "table2" tables on the "column" column.
-- A right join returns all rows from the right table and the matched rows from the left table.
SELECT * FROM table1 RIGHT JOIN table2 ON table1.column = table2.column;

-- Full outer join two or more tables
-- This full outer joins the "table1" and "table2" tables on the "column" column.
-- A full outer join returns all rows when there is a match in either the left or right table.
SELECT * FROM table1 FULL OUTER JOIN table2 ON table1.column = table2.column;

-- Cross join two or more tables
-- This cross joins the "table1" and "table2" tables.
-- A cross join returns the Cartesian product of the two tables, i.e., all possible combinations of rows.
SELECT * FROM table1 CROSS JOIN table2;

April 20, 2024

Zack Norris, my guy…
April 18, 2024

While scrolling YouTube
February 25, 2024

Red Dead Online

Red Dead Redemption

One of my absolute favorite online games…
February 18, 2024

Ubuntu Multipass: How to modify an instance

While instance properties can be determined at launch, some of them can be updated after the instance has been created. Specifically, an instance’s memory, disk space, and the number of its CPUs are exposed via daemon settings: local..(cpus|disk|memory).
Documentation
February 17, 2024

Saturday morning vibe…

Cleaning up some personal projects and performing some maintenance on some personal deployments.