Vasileios Paraskevas vparaskevas

nest.js

A multi-level groupBy for arrays inspired by D3's nest operator.

Nesting allows elements in an array to be grouped into a hierarchical tree structure; think of it like the GROUP BY operator in SQL, except you can have multiple levels of grouping, and the resulting output is a tree rather than a flat table. The levels in the tree are specified by key functions.

See this fiddle for live demo.

To be able to use PHP5 PDO with MS Access mdb files the following is required (the same applies for the PHP4 style of using odbc_X except for the obviously PDO specific requirements):

PHP ODBC module

In Linux this is achieved by intalling the php5-odbc package:

SSH Tunnel

Our db is hosted on Amazon. Our web server can connect to the db. Connections to the db are not allowed outside of the web server.

Run ssh tunnel locally:

This creates a tunnel from my local machine to the web server:

ssh -N -L 3307:my-rds-db.us-east-1.rds.amazonaws.com:3306 ec2-my-web-server.compute-1.amazonaws.com

OBSOLETE

This entire guide is based on an old version of Homebrew/Node and no longer applies. It was only ever intended to fix a specific error message which has since been fixed. I've kept it here for historical purposes, but it should no longer be used. Homebrew maintainers have fixed things and the options mentioned don't exist and won't work.

I still believe it is better to manually install npm separately since having a generic package manager maintain another package manager is a bad idea, but the instructions below don't explain how to do that.

Fixing npm On Mac OS X for Homebrew Users

Installing node through Homebrew can cause problems with npm for globally installed packages. To fix it quickly, use the solution below. An explanation is also included at the end of this document.

	# For each database:
	ALTER DATABASE database_name CHARACTER SET = utf8mb4 COLLATE = utf8mb4_unicode_ci;
	# For each table:
	ALTER TABLE table_name CONVERT TO CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_ci;
	# For each column:
	ALTER TABLE table_name CHANGE column_name column_name VARCHAR(191) CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_ci;
	# (Don’t blindly copy-paste this! The exact statement depends on the column type, maximum length, and other properties. The above line is just an example for a `VARCHAR` column.)

	(function(window, document, version, callback) {
	var j, d;
	var loaded = false;
	if (!(j = window.jQuery) \|\| version > j.fn.jquery \|\| callback(j, loaded)) {
	var script = document.createElement("script");
	script.type = "text/javascript";
	script.src = "/media/jquery.js";
	script.onload = script.onreadystatechange = function() {
	if (!loaded && (!(d = this.readyState) \|\| d == "loaded" \|\| d == "complete")) {
	callback((j = window.jQuery).noConflict(1), loaded = true);

	// === Arrays

	var [a, b] = [1, 2];
	console.log(a, b);
	//=> 1 2


	// Use from functions, only select from pattern
	var foo = () => [1, 2, 3];

	function getContrast50(hexcolor){
	return (parseInt(hexcolor, 16) > 0xffffff/2) ? 'black':'white';
	}

	function getContrastYIQ(hexcolor){
	var r = parseInt(hexcolor.substr(0,2),16);
	var g = parseInt(hexcolor.substr(2,2),16);
	var b = parseInt(hexcolor.substr(4,2),16);
	var yiq = ((r299)+(g587)+(b*114))/1000;
	return (yiq >= 128) ? 'black' : 'white';

	var mysql = require('mysql');

	var pool = mysql.createPool('mysql://localhost');

	inTransaction(pool, function(db, next) {
	db.query("DELETE * FROM stuff", function(err) {
	if (err) return next(err);

	db.query("INSERT INTO stuff VALUES (1,2,3)", function(err) {
	return next(err);