Chris Trinh chtrinh

I'm hunting for the best solution on how to handle keeping large sets of DB records "sorted" in a performant manner.

Problem Description

Most of us have work on projects at some point where we have needed to have ordered lists of objects. Whether it be a to-do list sorted by priority, or a list of documents that a user can sort in whatever order they want.

A traditional approach for this on a Rails project is to use something like the acts_as_list gem, or something similar. These systems typically add some sort of "postion" or "sort order" column to each record, which is then used when querying out the records in a traditional order by position SQL query.

This approach seems to work fine for smaller datasets, but can be hard to manage on large data sets with hundreds (or thousands) of records needing to be sorted. Changing the sort position of even a single object will require updating every single record in the database that is in the same sort group. This requires potentially thousands of wri

Synopsis

At the top of the file there should be a short introduction and/ or overview that explains what the project is. This description should match descriptions added for package managers (Gemspec, package.json, etc.)

Code Example

Show what the library does as concisely as possible, developers should be able to figure out how your project solves their problem by looking at the code example. Make sure the API you are showing off is obvious, and that your code is short and concise.

Motivation

ruby-1.9.3-p327 cumulative performance patch for rbenv

This installs a patched ruby 1.9.3-p327 with various performance improvements and a backported COW-friendly GC, all courtesy of funny-falcon.

Requirements

You will also need a C Compiler. If you're on Linux, you probably already have one or know how to install one. On OS X, you should install XCode, and brew install autoconf using homebrew.

	ActiveSupport.on_load(:active_record) do
	module Arel::NullsLastPredications
	def nulls_last
	Arel::Nodes::NullsLast.new self
	end
	end

	module Arel::Nodes
	class NullsLast < Unary
	def gsub *args

	# config/environments/production.rb

	# We're on Heroku, just output straight to STDOUT
	# This is required because we're using Unicorn: https://github.com/ryanb/cancan/issues/511#issuecomment-3643266
	config.logger = Logger.new(STDOUT)
	config.logger.level = Logger.const_get(ENV['LOG_LEVEL'] ? ENV['LOG_LEVEL'].upcase : 'INFO')

	# Working with Mac OS X 10.7, bash 1.3 (brew), git 1.7.4.4 (brew)
	# To get this to work, add a line to source it from your ~/.bashrc
	# Credit to Scott Bronson for the following tab completion workaround.
	# https://github.com/bronson/dotfiles/blob/731bfd951be68f395247982ba1fb745fbed2455c/.bashrc#L81
	# (only for bash, zsh tab completions are done separately.)
	__define_git_completion () {
	eval "
	_git_$2_shortcut () {
	COMP_LINE=\"git $2\${COMP_LINE#$1}\"
	let COMP_POINT+=$((4+${#2}-${#1}))

	var pubsub = {};
	(function(q) {
	var topics = {}, subUid = -1;
	q.subscribe = function(topic, func) {
	if (!topics[topic]) {
	topics[topic] = [];
	}
	var token = (++subUid).toString();
	topics[topic].push({
	token: token,

	## some useful aliases
	alias ls "ls -h"
	alias dir ls
	alias less more
	alias zless zmore
	alias bzless bzmore
	alias mirror "mirror -v"
	alias sync "mirror -R -v -n"
	alias reconnect "close; cache flush; cd ."
	alias edit "eval -f \"get $0 -o ~/.lftp/edit.tmp.$$ && shell \\\"cp -p ~/.lftp/edit.tmp.$$ ~/.lftp/edit.tmp.$$.orig && $EDITOR ~/.lftp/edit.tmp.$$ && test ~/.lftp/edit.tmp.$$ -nt ~/.lftp/edit.tmp.$$.orig\\\" && put ~/.lftp/edit.tmp.$$ -o $0; shell rm -f ~/.lftp/edit.tmp.$$*\""

	function keepTrying(otherArgs, promise) {
	promise = promise\|\|new Promise();

	// try doing the important thing

	if(success) {
	promise.resolve(result);
	} else {
	setTimeout(function() {
	keepTrying(otherArgs, promise);