rgreenjr

# open the ssh configuration file
sudo vi /etc/ssh/sshd_config

Make the following changes to /etc/ssh/sshd_config:

# disable password authentication
PasswordAuthentication no

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select to end of line

v g _

split arguments

g ,

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Sandi Metz

• Inheritance is not for sharing behavior
• Active Nothing (Null Object Pattern)
  • Must believe in nothing
• No such thing as one specialization
  • The new behavior is one thing and the original behavior is the other
  • Isolate the difference, name the concept, define the role, inject the players

Model Names

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# Taken from http://robots.thoughtbot.com/post/33706558963/migrating-data-from-an-upgraded-postgres
#
# Note: these steps assume installation with Homebrew.

# Initialize a new database, adding a .new suffix to the directory that Homebrew recommends.

initdb /usr/local/var/postgres.new -E utf8

# Run the upgrade script, providing the correct paths for the various flags.

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PostgreSQL Configuration Optimization

Memory

Only four values really matter:

• shared-buffers: below 2GB: set it to 20% of full memory; below 32GB: 25% of your full memory.

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-- show running queries (pre 9.2)
SELECT procpid, age(clock_timestamp(), query_start), usename, current_query 
FROM pg_stat_activity 
WHERE current_query != '<IDLE>' AND current_query NOT ILIKE '%pg_stat_activity%' 
ORDER BY query_start desc;

-- show running queries (9.2)
SELECT pid, age(clock_timestamp(), query_start), usename, query 
FROM pg_stat_activity 
WHERE query != '<IDLE>' AND query NOT ILIKE '%pg_stat_activity%' 

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Git Cheat Sheet

Common Commands

# stage all modified files being tracked
git add -u

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#!/usr/bin/env ruby -w
#
# Converts Gutenberg text files into spoken audio files.
#
require 'rubygems'

text = String.new
File.open(ARGV.first) { |f| text = f.read }
chapters = text.split(/^CHAPTER .*$/)
chapters.each_with_index do |chapter, index|

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#!/usr/bin/env ruby -w
#
# Trims Goodreads CSV files so they import into Delicious Library essential data only.
#

require 'rubygems'
require 'faster_csv'

path = ARGV.empty? ? "/Users/rgreen/Downloads/goodreads_export.csv" : ARGV[0]

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#!/usr/bin/env ruby -w
text = IO.read(ARGV.first)
words = text.split(/[^a-zA-Z]/)
freqs = Hash.new(0)
words.each { |word| freqs[word] += 1 }
freqs = freqs.sort_by { |x, y| y }
freqs.reverse!
freqs.each { |word, freq| puts sprintf("%20s %s", word, freq.to_s) }