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Postgres Distributed Key Generation

This SQL creates a Postgres function to generate sequential, numeric, unique IDs in a consistent format across services. Useful for database sharding or microservices.

Draws heavily on Instagram's ID generator, via Rob Conery, with minor modifications.

The main changes are that the unique number resolution is per-second rather than per-millisecond. This is to reduce key size below 2^53^-1 so that generated IDs that are under Javascripts Number.MAX_SAFE_INTEGER limit . This is important if you're using these on a Node.js server (e.g. our use case is an Express API using Hashids).

Max IDs are in the order of 51 bits, broken down as follows:

31 bits for the timestamp difference

	/** @jsx React.DOM */

	var STATES = [
	'AL', 'AK', 'AS', 'AZ', 'AR', 'CA', 'CO', 'CT', 'DE', 'DC', 'FL', 'GA', 'HI',
	'ID', 'IL', 'IN', 'IA', 'KS', 'KY', 'LA', 'ME', 'MD', 'MA', 'MI', 'MN', 'MS',
	'MO', 'MT', 'NE', 'NV', 'NH', 'NJ', 'NM', 'NY', 'NC', 'ND', 'OH', 'OK', 'OR',
	'PA', 'RI', 'SC', 'SD', 'TN', 'TX', 'UT', 'VT', 'VA', 'WA', 'WV', 'WI', 'WY'
	]

	var Example = React.createClass({

	var React = require('react');
	var cx = require('classnames');
	var vjs = require('video.js');
	var _forEach = require('lodash/collection/forEach');
	var _debounce = require('lodash/function/debounce');
	var _defaults = require('lodash/object/defaults');

	var DEFAULT_HEIGHT = 800;
	var DEFAULT_WIDTH = 600;
	var DEFAULT_ASPECT_RATIO = (9 / 16);

	CREATE SEQUENCE public.global_id_seq;
	ALTER SEQUENCE public.global_id_seq OWNER TO postgres;

	CREATE OR REPLACE FUNCTION public.id_generator()
	RETURNS bigint
	LANGUAGE 'plpgsql'
	AS $BODY$
	DECLARE
	our_epoch bigint := 1314220021721;
	seq_id bigint;

	CREATE TABLE accounts(
	id serial PRIMARY KEY,
	name VARCHAR(256) NOT NULL,
	parent_id INTEGER REFERENCES section,
	parent_path LTREE
	);

	CREATE INDEX account_parent_path_idx ON accounts USING GIST (parent_path);
	CREATE INDEX account_parent_id_idx ON accounts (parent_id);

	#!/bin/bash

	# A bash script to update a Cloudflare DNS A record with the external IP of the source machine
	# Used to provide DDNS service for my home
	# Needs the DNS record pre-creating on Cloudflare

	# Proxy - uncomment and provide details if using a proxy
	#export https_proxy=http://<proxyuser>:<proxypassword>@<proxyip>:<proxyport>

	# Cloudflare zone is the zone which holds the record