Anthony Cyrille ancyrweb

Migrations & Seeding

What are migrations??

Migrations are a way to make database changes or updates, like creating or dropping tables, as well as updating a table with new columns with constraints via generated scripts. We can build these scripts via the command line using knex command line tool.

To learn more about migrations, check out this article on the different types of database migrations!

Creating/Dropping Tables

Prologue

I wrote this answer on stackexchange, here: https://stackoverflow.com/posts/12597919/

It was wrongly deleted for containing "proprietary information" years later. I think that's bullshit so I am posting it here. Come at me.

The Question

Amazon is a SOA system with 100s of services (or so says Amazon Chief Technology Officer Werner Vogels). How do they handle build and release?

Moved to Shopify/graphql-design-tutorial

Directories on host machine:

/data/certbot/letsencrypt
/data/certbot/www
Nginx server in docker container

docker run -d --name nginx \

	function slugify(text)
	{
	return text.toString().toLowerCase()
	.replace(/\s+/g, '-') // Replace spaces with -
	.replace(/[^\w\-]+/g, '') // Remove all non-word chars
	.replace(/\-\-+/g, '-') // Replace multiple - with single -
	.replace(/^-+/, '') // Trim - from start of text
	.replace(/-+$/, ''); // Trim - from end of text
	}

	Latency Comparison Numbers (~2012)
	----------------------------------
	L1 cache reference 0.5 ns
	Branch mispredict 5 ns
	L2 cache reference 7 ns 14x L1 cache
	Mutex lock/unlock 25 ns
	Main memory reference 100 ns 20x L2 cache, 200x L1 cache
	Compress 1K bytes with Zippy 3,000 ns 3 us
	Send 1K bytes over 1 Gbps network 10,000 ns 10 us
	Read 4K randomly from SSD* 150,000 ns 150 us ~1GB/sec SSD

	; /usr/local/bin/nasm -f macho 32.asm && ld -macosx_version_min 10.7.0 -o 32 32.o && ./32

	global start

	section .text
	start:
	push dword msg.len
	push dword msg
	push dword 1
	mov eax, 4

	/**
	* A linear interpolator for hexadecimal colors
	* @param {String} a
	* @param {String} b
	* @param {Number} amount
	* @example
	* // returns #7F7F7F
	* lerpColor('#000000', '#ffffff', 0.5)
	* @returns {String}
	*/

	# This file is: ~/.ssh/config

	# You may have other (non-CodeCommit) SSH credentials stored in this
	# config file – in addition to the CodeCommit settings shown below.

	# NOTE: Make sure to run [ chmod 600 ~/.ssh/config ] after creating this file!

	# Credentials for Account1
	Host awscc-account1 # 'awscc-account1' is a name you pick
	Hostname git-codecommit.us-east-1.amazonaws.com # This points to CodeCommit in the 'US East' region

	import { autorun } from "mobx";

	import { createStore, Action, Reducer } from "./remox"

	interface Person { firstName: string; lastName: string; }

	interface SetFirstName { type: "SET_FIRST_NAME", newFirstName: string; }
	interface SetLastName { type: "SET_LAST_NAME", newLastName: string; }

	function personReducer(state:Person, action: SetFirstName \| SetLastName) {