Thanh Nguyen memoryonrepeat

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	#!/bin/bash

	# Dependencies: dynamo-archive
	# In case there is some big tables, it is advisable to dedicate a process for each big table
	# and another process for the rest, since this can work in parallel
	# Can use https://github.com/bchew/dynamodump which is faster and easier

	key=<AWS access key>
	secret=<AWS secret>
	region=<AWS region>

	# List all process whose name contains some string
	ps aux \| grep <string>

	# List all process listening to a particular port
	lsof -i :<port number>

	# List all running processes
	ps -A

	# Killall process that match a specific name

	# Connect to remote redis server
	# Note: If server is hosted on EC2, it's isolated inside VPC and doesn't have ICMP available.
	# Therefore, either do the command from inside EC2 or setup SSH tunnel to run from local
	redis-cli -h <server IP address> -p <port> [command]

	# Install Redis properly on server (rmb to change daemon to 'yes' in redis.conf)
	# If failed, do it manually according to this guide http://redis.io/topics/quickstart
	sudo ./utils/install-server.sh

	# Start redis server as a daemon (need to install using the above method first)

	# ssh tunneling through a remote server
	# local port forwarding
	# -f is for ssh to go to background
	# -N is to not execute a command on remote host
	ssh -L <local port>:<destination host>:<destination port> <remote username>@<remote host> -f -N

	# then either go to http://localhost:<local port> or in case using DBs like Redis
	# Example: ssh -L 3001:google.com:80 [email protected] will forward all http://localhost:3001 through server.com to google.com:80
	# Example: ssh -L 3001:redishost.com:6379 [email protected]
	# then

	# Querying using query() is only allowed for primary and indexed keys. This work around allows querying using any field.

	aws dynamodb scan --table-name <TABLE> --filter-expression "fieldname = :c" --expression-attribute-values file://expression-attribute-values.json > <OUTPUT>.json

	# Remove the property from the item

	aws dynamodb update-item --table-name <TABLE_NAME> --key file://key.json --update-expression "REMOVE #X" --expression-attribute-names file://expression-attribute-names.json --return-values ALL_NEW

	General philosophy:
	- Unit test -> Prune (to reduce complexity) -> Test -> Redesign -> Test -> Redecorate -> Test -> New feature -> Test

	Create a ~/.profile to let any kind of shell inherit from it
	When executing a command, do note what kind of shell it's executing on top of.