odlp

# Export table to CSV from psql:
COPY table_name TO 'filepath' WITH DELIMITER AS ',' CSV HEADER;

odlp

result = ActiveRecord::Base.connection.execute("SELECT DISTINCT SUBSTRING(postcode, '[A-Z0-9]{3,} [0-9]{1}') FROM postcodes")

result.values.first
# => ['AB1 1']

odlp

# Convert file encoding for CSV in OS X:
iconv -f iso-8859-1 -t UTF-8 original.csv > utf-output.csv
 
# Where 
# -f is current encoding
# -t is target encoding
 
# Guestimate of original file encoding with:
file -I

odlp

puts `clear`
exercises = ["How much wood can a woodchuck chuck?", "What's the time Mr.Wolf?", "Peter Piper picked a peck of pickled peppers."]
def check_diff text, input
  text.length.times.map{|i| 1 unless text.chars[i] == input.chars[i]}.count(1) + (input.length > text.length ? input.length - text.length : 0)
end
exercises.each do |exercise|
  puts "Type the following:\n---\n#{exercise}\n---\n\n"
  start_time, input, end_time = Time.now, gets.chomp, Time.now
  puts "Mistakes: #{check_diff(exercise, input)} characters. Time taken: #{(end_time - start_time).round(2)} seconds.\n\n"
end

odlp

# EXAMPLE 1: Cascade
# Two modules happen to have the same method ('say').
# If we include the Shouting module last, the Shouting 'say' method overwrites the Talkable 'say' method.

module Talkable
  def say (str)
    puts str
  end
end