Graham Duncan duncangh

Key/Command	Description
Tab	Auto-complete files and folder names
Ctrl + A	Go to the beginning of the line you are currently typing on
Ctrl + E	Go to the end of the line you are currently typing on
Ctrl + U	Clear the line before the cursor
Ctrl + K	Clear the line after the cursor
Ctrl + W	Delete the word before the cursor
Ctrl + T	Swap the last two characters before the cursor

Bootstrap: Navbar with submenus

Magic words:

psql -U postgres

Some interesting flags (to see all, use -h or --help depending on your psql version):

-E: will describe the underlaying queries of the \ commands (cool for learning!)
-l: psql will list all databases and then exit (useful if the user you connect with doesn't has a default database, like at AWS RDS)

This is a simple chat-like program using pub-sub pattern, backed by PostgreSQL's LISTEN/NOTIFY command.

publish message to foo channel from user nickname.

$ python pub.py foo nickname
PUBLISH to channel #foo

	<html>
	<head>
	<link href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.4/css/bootstrap.min.css" rel="stylesheet" />
	<link href="https://codepen.io/jstneg/pen/vbfqy" rel="stylesheet" />
	<style>
	.dropdown-submenu{ position: relative; }

	.dropdown-submenu>.dropdown-menu{
	top:0;
	left:100%;

	import os

	import boto3
	from flask import Flask, render_template, request, url_for, redirect

	app = Flask(__name__)

	AWS_ACCESS_KEY_ID = os.environ['AWS_ACCESS_KEY_ID']
	AWS_SECRET_ACCESS_KEY = os.environ['AWS_SECRET_ACCESS_KEY']
	S3_BUCKET = os.environ['S3_BUCKET']

	-- Create a group
	CREATE ROLE readaccess;

	-- Grant access to existing tables
	GRANT USAGE ON SCHEMA public TO readaccess;
	GRANT SELECT ON ALL TABLES IN SCHEMA public TO readaccess;

	-- Grant access to future tables
	ALTER DEFAULT PRIVILEGES IN SCHEMA public GRANT SELECT ON TABLES TO readaccess;

	import pandas as pd
	import numpy as np
	import re

	# ================================================
	class option_parser:
	def __init__(self, symbol, response):
	self.symbol = symbol
	self.response = response
	# ------------------------------------------------

	#Spider Websites with Wget – 20 Practical Examples

	Wget is extremely powerful, but like with most other command line programs, the plethora of options it supports can be intimidating to new users. Thus what we have here are a collection of wget commands that you can use to accomplish common tasks from downloading single files to mirroring entire websites. It will help if you can read through the wget manual but for the busy souls, these commands are ready to execute.

	1. Download a single file from the Internet
	wget http://example.com/file.iso

	2. Download a file but save it locally under a different name
	wget ‐‐output-document=filename.html example.com

	# coding=UTF-8
	from __future__ import division
	import re

	# This is a naive text summarization algorithm
	# Created by Shlomi Babluki
	# April, 2013


	class SummaryTool(object):