FKs are in your way to shard your database. Your app is accustomed to rely on FK to maintain integrity, instead of doing it on its own. It may even rely on FK to cascade deletes (shudder). When eventually you want to shard or extract data out, you need to change & test the app to an unknown extent.

To boil everything down to a bullet list, the differences Firefox Developer Edition bring to the table include: A separate profile so your development environment can be configured differently to your regular browsing environment Access to cutting edge features not available elsewhere A 12 week lead time on support for the newest additions to web standards Default preferences tuned for developers Dark theme style out of the box

“Why don’t you assume you’ve written your book already — and all you have to do now is find it?”

Here’s Stephen Harrigan (talking about his book, Big Wonderful Thing: A History of Texas)

In my experience writing books, it isn’t just a “resistance” thing or a “perfectionist” thing or a fear thing, it’s more about research and wondering if you’ve done enough of it. Research becomes your way of procrastinating, because, let’s face it, research is just more fun than writing. (Me, personally, I became a professional writer so I could be a professional reader.)

There’s an awful temptation to just keep on researching. There comes a point where you just have to stop, and start writing. When I began, I thought that the way one should work was to do all the research and then write the book. In time I began to understand that it’s when you start writing that you really find out what you don’t know and need to know.

great place to start finding circuit schematic is the Discover Circuits site. They have a comprehensive list of fun circuits to experiment with

Step 19: Your Third Circuit

Step 18: Your Second Circuit

Step 17: Your First Circuit

designed to allow you to be able to insert an integrated circuit into the center

To use wire in your circuit, simply cut a piece to size, strip a 1/4" of insulation from each end of the wire and use it to connect points together on the breadboard

When things are wired in parallel, they are wired side by side, such that electricity passes through all of them at the same time, from one common point to another common point

When things are wired in series, things are wired one after another, such that electricity has to pass through one thing, then the next thing, then the next, and so on

circuit is a complete and closed path through which electric current can flow

electricity is typically defined as having a voltage and a current rating

it is recommended that you use insulated 22awg (22 gauge) solid core wire

Wires are nice because they allow you to connect things without adding virtually no resistance to the circuit

there typically runs two continuous bus lines. One is intended as a power bus and the other is intended as a ground bus

They are covered with a grid of holes, which are split into electrically continuous rows. In the central part there are two columns of rows that are side-by-side

Breadboards are special boards for prototyping electronics

Batteries are represented in a circuit by a series of alternating lines of different length

battery is a container which converts chemical energy into electricity

This is dependent on the type of switch it is

switch is basically a mechanical device that creates a break in a circuit. When you activate the switch, it opens or closes the circuit

it is ideal to light up multiple LEDs by wiring them in parallel

Like all diodes, LEDs create a voltage drop in the circuit, but typically do not add much resistance

special type of diode that lights up when electricity passes through it. Like all diodes, the LED is polarized and electricity is only intended to pass through in one direction

For instance, if you have two 10K resistors in series between power (5V) and ground (0V), the point where these two resistors meet will be half the power supply (2.5V) because both of the resistors have identical values

current is rated in Amps

integrated circuit is an entire specialized circuit that has been miniaturized and fit onto one small chip with each leg of the chip connecting to a point within the circuit. These miniaturized circuits typically consist of components such as transistors, resistors, and diodes

PNP transistors allow electricity to pass from the emitter pin to the collector pin

NPN transistors allow electricity to pass from the collector pin to the emitter pin

transistor takes in a small electrical current at its base pin and amplifies it such that a much larger current can pass between its collector and emitter pins. The amount of current that passes between these two pins is proportional to the voltage being applied at the base pin

the other side connects to power

The ring found on one end of the diode indicates the side of the diode which connects to ground

Diodes are components which are polarized. They only allow electrical current to pass through them in one direction. This is useful in that it can be placed in a circuit to prevent electricity from flowing in the wrong direction

Ceramic disc capacitors are non-polarized, meaning that electricity can pass through them no matter how they are inserted in the circuit

Electrolytic capacitors are typically polarized. This means that one leg needs to be connected to the ground side of the circuit and the other leg must be connected to power. If it is connected backwards, it won't work correctly

capacitor is a component that stores electricity and then discharges it into the circuit when there is a drop in electricity

With alternating current, the direction electricity flows throughout the circuit is constantly reversing

resistors add resistance to the circuit and reduces the flow of electrical current. It is represented in a circuit diagram as a pointy squiggle with a value next to it

electricity in a circuit must be used

With Direct Current, electricity flows in one direction between power and ground

Potentiometers are measured in ohms like resistors, but rather than having color bands, they have their value rating written directly on them (i.e. "1M"). They are also marked with an "A" or a "B, " which indicated the type of response curve it has

Potentiometers are variable resistors. In plain English, they have some sort of knob or slider that you turn or push to change resistance in a circuit. If you have ever used a volume knob on a stereo or a sliding light dimmer, then you have used a potentiometer

The round notch on one edge of the IC chip indicates the top of the chip. The pin to the top left of the chip is considered pin 1. From pin 1, you read sequentially down the side until you reach the bottom (i.e. pin 1, pin 2, pin 3..). Once at the bottom, you move across to the opposite side

As a beginner, you will be mainly working with DIP chips. These have pins for through-hole mounting. As you get more advanced, you may consider SMT chips which are surface mount soldered to one side of a circuit board

you can learn all about integrated circuits by looking up their datasheets. On the datasheet you will learn the functionality of each pin. It should also state the voltage and current ratings of both the chip itself and each individual pin

There are two basic types of transistors, which are NPN and PNP

They are represented in schematic as a line with a triangle pointing at it

it requires energy to pass through a diode and this results in a drop of voltage. This is typically a loss of about 0.7V

The most commonly encountered types of capacitors are ceramic disc capacitors that look like tiny M&Ms with two wires sticking out of them and electrolytic capacitors that look more like small cylindrical tubes with two wires coming out the bottom (or sometimes each end)

Capacitors are measured in Farads

Any resistor of over 1000 ohms is typically shorted using the letter K. For instance, 1,000 would be 1K

Anyhow... a resistor with the markings brown, black, orange, gold will translate as follows: 1 (brown) 0 (black) x 1,000 = 10,000 with a tolerance of +/- 5%

You read the values from left to right towards the (typically) gold band

two different ways in which you can wire things together called series and parallel

switch does not add any resistance to a circuit and simply adding a switch between power and ground will create a short circuit

Always make sure that you never accidentally connect positive voltage to ground while wiring things in parallel

electricity always follows the path of least resistance to ground

It is very important to prevent short circuits by making sure that the positive voltage is never wired directly to ground

Shorts are bad because they will result in your battery and/or circuit overheating, breaking, catching on fire, and/or exploding

there needs to be something wired between positive and ground that adds resistance to the flow of electricity and uses it up. If positive voltage is connected directly to ground and does not first pass through something that adds resistance, like a motor, this will result in a short circuit

Voltage is obviously rated in Volts

There are two types of electrical  signals , those being alternating current (AC), and direct current (DC)

The rate of reversal is measured in Hertz, which is the number of reversals per second

The result of the uniform interface is that requests from different clients look the same, whether the client is a chrome browser, a linux server, a python script, an android app or anything else

The client can request code from the server, and then the response from the server will contain some code, usually in the form of a script, when the response is in HTML format. The client then can execute that code

data the server sends contain information about whether or not the data is cacheable. If the data is cacheable, it might contain some sort of a version number. The version number is what makes caching possible: since the client knows which version of the data it already has (from a previous response), the client can avoid requesting the same data again and again

In order for an API to be RESTful, it has to adhere to 6 constraints

there might be a number of servers in the middle. These servers might provide a security layer, a caching layer, a load-balancing layer, or other functionality

Stateless means the server does not remember anything about the user who uses the API

client and the server act independently, each on its own, and the interaction between them is only in the form of requests, initiated by the client only, and responses, which the server send to the client only as a reaction to a request

Uniform interface

What the server does when you, the client, call one of its APIs depends on 2 things that you need to provide to the server

The representation of the state can be in a JSON format, and probably for most APIs this is indeed the case. It can also be in XML or HTML format

It means when a RESTful API is called, the server will transfer to the client a representation of the state of the requested resource.

RESTful web application exposes information about itself in the form of information about its resources. It also enables the client to take actions on those resources, such as create new resources (i.e. create a new user) or change existing resources (i.e. edit a post).

A single on/off decision is best understandable using a toggle switch.

A single yes/no option is more usable with a checkbox.

Independent items use toggle switches for selection.

To select related items in a list, use checkboxes.

Sometimes toggle switch does not clearly indicate whether it is a state or action.

Indeterminate state is best shown using a checkbox

Selecting multiple options in a list provides better experience using checkboxes.

Checkboxes are preferred when an explicit action is required to apply settings.

The options that require instant response are best selected using a toggle switch.

The children watched an educational video that included clips from Sesame Street and covered math topics such as counting and addition as well as reading topics for comparison

boys and girls as old as 8 had similar abilities when it came to perceiving numbers and grasping elementary mathematics concepts

study of 104 children from ages 3 to 10 found similar patterns of brain activity in boys and girls as they engaged in basic math tasks

factors other than biological differences explain why girls are less likely to pursue degrees and jobs in math and science

males may be more likely to choose science because they are less likely than females to have strong reading, writing and language skills

women in these countries are under less pressure to choose a field that promises an economic payback and have more freedom to pursue what interests them most.

Yet paradoxically, females in wealthier countries with more gender equality, including the U.S., were less likely than females in other countries to get degrees in fields such as math and computer science.

Chords with low uncertainty and high surprise, and vice versa, evoked high pleasure

With every negative emotion you’re experiencing, ask yourself: “Why am I feeling this? Is there a past experience that’s triggering this?”In short – sit with your discomforts, don’t run from them

Be careful of excess coffee consumption – it’s very destructive to the adrenal glands

The average American adult is sleeping 6 hours and 31 minutes per night 

A tiny percentage of people have the DEC2 gene, a genetic mutation that produces a short sleeping phenotype“The probability that you are a DEC2 carrier is very low… You’re far more likely to be struck by lightning in your lifetime.” – Dr. Matthew WalkerPeople with the DEC2 gene only need ~6.25 hours of sleep per night

Here’s a final tally for our comparison

BFS looks at each adjacent node and doesn't consider the children of those adjacent nodes. DFS looks at each adjacent node, and looks at all the children of the current adjacent nodes. It again, looks at the children of the next adjacent node (adjacent to the children of the prevoius)

Humans are worse at this because we all have different goals, whereas all ants work towards the survival of their colonies.

The big idea behind Brave is that instead of supporting websites by viewing their banner ads, you can pay them directly through your browser

Tutorials and how-to guides are similar because they are both concerned with describing practical steps, while what how-to guides share with technical referenceis that they’re what we need when we are actually at work, coding. Reference guides and explanation are similar because they’re concerned with theoretical knowledge, and finally, what tutorials have in common with explanation is that they are most useful when we are studying, rather than actually working

Summary: Napping

NapNumber = 5.6 - 0.8*CoreSleep

NapDuration = (SleepRequired - SleepObtained) / 3

Six naps no sleep; 4 naps one-point-five hours sleep; 3 naps three hours sleep; 2 naps four-point-five hours sleep; one nap six hours sleep*.

"Everyman sleep schedule". Were it not for that gravitation and a tendency to take a "core sleep", I might even suspect that the inventor of the Uberman sleep cycle suffered from a rare mutation that causes circadian arrhythmicity. People with that disorder cannot sleep well in a long block over the night and take multiple naps during the day

Even though naps provide an excellent compensation for lost sleep in the night, they cannot provide a full functional replacement. To achieve your maximum cognitive capacity, you need to run your night sleep uninterrupted until completion!

Early naps will not provide full compensation. Late naps will last longer and will shorten sleep in the following night

For a nap to express its full power, the following conditions must be met (in order of importance): it should take place at the center of the midday circadian nadir (see: Best nap timing). This corresponds with Mediterranean siesta it cannot be regulated with alarm clocks, caffeine, or other sleep "tricks". Coffee naps are a good idea for people in a hurry, not for those who care about brain productivity it should be the only nap of the day (i.e. it cannot be part of a polyphasic sleep schedule) it works best in free running sleep with no sleep deficit it works best in people with no physical or mental health issues it works best in habitual nappers who improved the quality of their naps from month to month by adjusting and perfecting little details in their surroundings. Beginners are often too anxious to fall asleep

each hour of lost night sleep requires 20 min. of replacement nap time

The art of napping has the power to double creative productivity. Churchill was a famous biphasic sleeper. His naps let him squeeze two productive days into 24 hours

Analysis of data collected in 1970 from 48.738 young Swedish men, compared to national suicide registers, shows that lower intelligence increases suicide risk. Low emotional control significantly contributes to suicide in young men, but becomes less of a factor with age. Low intelligence, however, remains a significant contributor to male suicide throughout life.

In general, use synchronous communication when the following is true

Pyramid of Remote Team Communication post.

It’s hard to build rapport and personal relationships with only written communication

Slack boasts that users spend 9+ hours per workday connected to the app. 90 minutes of active usage spread over 9 hours is a whole lot of interruptions.

2015 study conducted by Yahoo Labs found that the most common email response time was just 2 minutes

synchronous communication is when you send a message and the recipient processes the information and responds immediately. In-person communication, like meetings, are examples of purely synchronous communication

asynchronous communication is when you send a message without expecting an immediate response. For example, you send an email. I open and respond to the email several hours later

Study after study after study into remote work has made one thing clear: Remote workers are more productive than their office-bound counterparts.

The top reasons why a product fails:It’s too complicated – simplicity is kingIt doesn’t spread by word-of-mouthIt doesn’t take advantage of the power of iterationThe founder is too fearful of creating something novelIt’s not launched into a community

When you say “yes” to something, you’re basically saying “no” to 1,000 other things

principle of least privilege states that any process, user or program has only the privileges it needs to do its job

If you really want to impress your security consultant, then casually mention Kerckhoffs Principle which is a more formal way of saying ‘security through obscurity is not sufficient’

Hashing is the process of turning one set of data into another through a reproducible algorithm

symmetric key is. It’s a key that is ‘the same’ one used on both sides of the communication

asymmetric key is one where access to the key used to encrypt the message does not imply access to decrypt the message

Authorization is the process of determining whether you are allowed to do something or not

Security through obscurity is security through the design of a system. In other words, if the design of your system were to become public then it would be easy to expose

Role-Based Access Control gives permission to a more abstract entity called a role. Rather than giving access to that user directly, you give the user access to the role, and then that role has the access permissions set for it

This is why it’s important to ‘salt‘ your hash with a secret key so that knowledge of the hash algorithm isn’t enough to crack a lot of passwords

Encryption vs Encoding

for many women and purple can induce soothing and calmness with the image of royalty

Colours and emotion 

Both men and women have blue as their top colour

The colours black & white have opposing meaning in western and eastern cultures

Think of each colour in context of its environment, for example do you have a mostly grey, white or muted colours on your website then make your call to action button(s) green or red

our brain processes visuals 60,000x faster than text

Colour is such a pervasive part of everything we encounter visually in our world, it evokes emotions which in turn drives decision making

When creating or refining your brand identity think about pairing your main colour with a complimentary colour or use the 3 grouping guides below

We are using colour to communicate the value of our product or service

our eyes can only pick up certain light wavelengths

The theory of colour is a discipline that stretches back to at least the 15th century. It encompasses chemistry, physics and mathematics to effectively explain colour

There are 2 primary colour systems (to reproduce colour) we use on a daily basis additive & subtractive. Anything that emits light (sun, screen or projector) uses additive and everything else reflects colour and uses subtractive colour

The colour wheel is where you need to start when planning a colour scheme or branding for your business and for sales and marketing campaigns. The colour wheel consists of primary, secondary and tertiary colours.

round shapes are more trustworthy & straight sharp edges are more striking

“When scientists analyze people who appear to have tremendous self-control, it turns out those individuals aren’t all that different from those who are struggling. Instead, “disciplined” people are better at structuring their lives in a way that does not require heroic willpower and self-control.” - Atomic Habits

“The professional has learned that success, like happiness, comes as a by-product of work.” - The War of Art

“To write a great book, you must first become the book.”  - Atomic Habits

I could and probably will write an entire article (or 10) on how I approach SEO research, but for the purpose of this article, I’ll just share that I use these tools: Ahrefs, Keyword Planner, and Keywords Everywhere.

Conversations, books and articles, personal experiences, and random Google searches

What is something that I can uniquely contribute?

I set an open invitation to my brain to take note of anything interesting. More specifically, I look for anything within the intersection of: (1) interesting, (2) doesn’t exist online in that exact form, and (3) something I can contribute uniquely to

In my opinion, writing should never be something that you do just to check off of your to-do list. At its core, writing is a mechanism to try to deliver value to others. And over time, I’ve defined that as my core goal.

There’s a great tool called Draftback, which essentially lets you “go back in time to look over your own shoulder as you write”

Writing Process Steps:Ideation: PassiveTracking: ActiveOutline - ActiveIdea Arbitrage - PassiveResearch - ActiveWriting - Active

Practice makes any seemingly impossible task familiar

LINQ (a querying syntax in C# and VB.NET) uses the order FROM ... WHERE ... SELECT

Database engines in practice don’t actually run queries by joining, and then filtering, and then grouping, because they implement a bunch of optimizations reorder things to make the query run faster as long as reordering things won’t change the results of the query

SELECT isn’t the first thing, it’s like the 5th thing!

The vertical bar on the letter T represents the depth of related skills and expertise in a single field, whereas the horizontal bar is the ability to collaborate across disciplines with experts in other areas and to apply knowledge in areas of expertise other than one's own.

To address the availability concern, new architectures were developed to minimize the impact of partitions. For instance, splitting data sets into smaller ranges called shards can minimize the amount of data that is unavailable during partitions. Furthermore, mechanisms to automatically alter the roles of various cluster members based on network conditions allow them to regain availability quickly

typically less flexible and generalized than their more conventional relational counterparts. They also usually only offer a subset of full SQL and relational features, which means that they might not be able to handle certain kinds of usage. Many NewSQL implementations also store a large part of or their entire dataset in the computer's main memory. This improves performance at the cost of greater risk to unpersisted changes

using a mixture of different database types is the best approach for handling the data of your projects

best suited for use cases with high volumes of relational data in distributed, cloud-like environments

CAP theorem is a statement about the trade offs that distributed databases must make between availability and consistency. It asserts that in the event of a network partition, a distributed database can choose either to remain available or remain consistent, but it cannot do both. Cluster members in a partitioned network can continue operating, leading to at least temporary inconsistency. Alternatively, at least some of the disconnected members must refuse to alter their data during the partition to ensure data consistency

NewSQL databases: bringing modern scalability and performance to the traditional relational pattern

aggregate queries like summing, averaging, and other analytics-oriented processes can be difficult or impossible

Column-family databases are good when working with applications that requires great performance for row-based operations and highly scalability

it helps to think of column family databases as key-value databases where each key (row identifier) returns a dictionary of arbitrary attributes and their values (the column names and their values)

Column-family databases: databases with flexible columns to bridge the gap between relational and document databases

querying for the connection between two users of a social media site in a relational database is likely to require multiple table joins and therefore be rather resource intensive. This same query would be straightforward in a graph database that directly maps connections

Graph databases are most useful when working with data where the relationships or connections are highly important

network databases require step-by-step traversal to travel between items and are limited in the types of relationships they can represent.

Graph databases: mapping relationships by focusing on how connections between data are meaningful

Document databases: Storing all of an item's data in flexible, self-describing structures

Document databases are a good choice for rapid development because you can change the properties of the data you want to save at any point without altering existing structures or data. You only need to backfill records if you want to. Each document within the database stands on its own with its own system of organization. If you're still figuring out your data structure and your data is mainly composed discrete entries that don't include a lot of cross references, a document database might be a good place to start. Be careful, however, as the extra flexibility means that you are responsible for maintaining the consistency and structure of your data, which can be extremely challenging

Though the data within documents is organized within a structure, document databases do not prescribe any specific format or schema

Key-value stores are often used to store configuration data, state information, and any data that might be represented by a dictionary or hash in a programming language. Key-value stores provide fast, low-complexity access to this type of data

Key-value databases: simple, dictionary-style lookups for basic storage and retrieval

NoSQL databases: modern alternatives for data that doesn't fit the relational paradigm

relational databases are often a good fit for any data that is regular, predictable, and benefits from the ability to flexibly compose information in various formats. Because relational databases work off of a schema, it can be more challenging to alter the structure of data after it is in the system. However, the schema also helps enforce the integrity of the data, making sure values match the expected formats, and that required information is included. Overall, relational databases are a solid choice for many applications because applications often generate well-ordered, structured data

querying language called SQL, or structured query language, was created to access and manipulate data stored with that format

Relational databases: working with tables as a standard solution to organize well-structured data

database schema is a description of the logical structure of a database or the elements it contains. Schemas often include declarations for the structure of individual entries, groups of entries, and the individual attributes that database entries are comprised of. These may also define data types and additional constraints to control the type of data that may be added to the structure

Network databases: mapping more flexible connections with non-hierarchical links

Hierarchical databases: using parent-child relationships to map data into trees

Hierarchical databases are not used much today due to their limited ability to organize most data and because of the overhead of accessing data by traversing the hierarchy

The first flat file databases represented information in regular, machine parse-able structures within files. Data is stored in plain text, which limits the type of content that can be represented within the database itself. Sometimes, a special character or other indicator is chosen to use as a delimiter, or marker for when one field ends and the next begins. For example, a comma is used in CSV (comma-separated values) files, while colons or white-space are used in many data files in Unix-like systems

Some advantages of this format

While flat file databases are simple, they are very limited in the level of complexity they can handle

One of the earliest interactions with a customer is to signal a lack of trust. The bartender is suggesting the customer will leave without paying.

I think many business owners do not consider the subconscious effects on how they manage their business

In another example, there is a plaza near where I work that has a number of eating options but my preferred is a sandwich place at the far end of the building. When I pull in I often look for parking in front, if there is not I might need to go to the opposite end of the plaza to find parking. While walking to the sandwich shop I pass by 3 other places to eat. I almost never make it to the sandwich shop. I always convince myself to try something different before getting to the front door of my go-to lunch spot

the experience his customers have while visiting him was very important to him and it started when they pulled into the parking lot. In his view, they should have front row parking

"Secrecy is the first law of Magic" - from Julia Cameron's Artist's Way.Talking about your project seems to spread your energy in every direction other than towards completion.