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Effective Engineer - Notes

• By Edmond Lau
• Highly Recommended 👍
• http://www.theeffectiveengineer.com/

What's an Effective Engineer?

• They are the people who get things done. Effective Engineers produce results.

Adopt the Right Mindsets

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Keybase proof

I hereby claim:

• I am n3bulous on github.
• I am kmcfadden (https://keybase.io/kmcfadden) on keybase.
• I have a public key ASDsqs5_YHvYC13MGy9GZzANdPeNvMwv96qfGUokvTR7kAo

To claim this, I am signing this object:

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pluck_in_batches

Sometimes you need to iterate over a ton of items and you don't want the overhead of creating AR objects out of all of them. Hell, you only need a few things! Well, #pluck has your back.

But what if you want to iterate over many tonnes of items?

Pluck in batches to the rescue!

This fork works on any orderable primary key not just integers just like http://api.rubyonrails.org/classes/ActiveRecord/Batches.html#method-i-find_in_batches

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 class AddEnvironmentToHost < ActiveRecord::Migration
     def self.up
-        add_column :hosts, :environment, :string
+        unless ActiveRecord::Base.connection.columns(:hosts).collect {|c| c.name}.include?("environment")
+            add_column :hosts, :environment, :string
+        end
     end
     
     def self.down
-        remove_column :hosts, :environment

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AWS Elastic Beanstalk deploy user restricted IAM policy

An IAM user policy document to give minimal rights for deploying an Elastic Beanstalk application.

Where:

• REGION: AWS region.
• ACCOUNT_ID: AWS account ID.
• APPLICATION_NAME: Desired target Elastic Beanstalk application name(space).
• IAM_INSTANCE_PROFILE_ROLE: The instance profile (IAM role) Elastic Beanstalk EC2 instaces will run under.

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DELIMITER |

CREATE FUNCTION uuid_from_bin(b BINARY(16))
RETURNS CHAR(36) DETERMINISTIC
BEGIN
  DECLARE hex CHAR(32);
  SET hex = HEX(b);
  RETURN LOWER(CONCAT(LEFT(hex, 8), '-', MID(hex, 9,4), '-', MID(hex, 13,4), '-', MID(hex, 17,4), '-', RIGHT(hex, 12)));
END
|

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#!/bin/bash
#
# The MIT License
#
# Copyright 2014 Jakub Jirutka <[email protected]>.
#
# Permission is hereby granted, free of charge, to any person obtaining a copy
# of this software and associated documentation files (the "Software"), to deal
# in the Software without restriction, including without limitation the rights
# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell

n3bulous

Keybase proof

I hereby claim:

• I am n3bulous on github.
• I am kmcfadden (https://keybase.io/kmcfadden) on keybase.
• I have a public key whose fingerprint is CFB8 A03D 32F5 75C5 0B43 F2F7 68BC 0C53 69A2 0530

To claim this, I am signing this object:

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// Use Gists to store code you would like to remember later on
console.log(window); // log the "window" object to the console

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# An example of the below

virtualenv "/home/dvcsmirrors/hg" do
    owner "root"
    group "dvcsmirrors"
    mode 0775
    packages "Mercurial" => "1.6.3",
             "hgsubversion" => "1.1.2"
end