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select
    p.ID as order_id,
    p.post_date,
    max( CASE WHEN pm.meta_key = '_billing_email' and p.ID = pm.post_id THEN pm.meta_value END ) as billing_email,
    max( CASE WHEN pm.meta_key = '_billing_first_name' and p.ID = pm.post_id THEN pm.meta_value END ) as _billing_first_name,
    max( CASE WHEN pm.meta_key = '_billing_last_name' and p.ID = pm.post_id THEN pm.meta_value END ) as _billing_last_name,
    max( CASE WHEN pm.meta_key = '_billing_address_1' and p.ID = pm.post_id THEN pm.meta_value END ) as _billing_address_1,
    max( CASE WHEN pm.meta_key = '_billing_address_2' and p.ID = pm.post_id THEN pm.meta_value END ) as _billing_address_2,
    max( CASE WHEN pm.meta_key = '_billing_city' and p.ID = pm.post_id THEN pm.meta_value END ) as _billing_city,
    max( CASE WHEN pm.meta_key = '_billing_state' and p.ID = pm.post_id THEN pm.meta_value END ) as _billing_state,

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SELECT wp_users.user_login, wp_users.user_email, firstmeta.meta_value as first_name, lastmeta.meta_value as last_name FROM wp_users left join wp_usermeta as firstmeta on wp_users.ID = firstmeta.user_id and firstmeta.meta_key = 'first_name' left join wp_usermeta as lastmeta on wp_users.ID = lastmeta.user_id and lastmeta.meta_key = 'last_name'

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git log --since="last month" --pretty=format:'%h,%an,%ar,%s' > log.csv

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Gemfile

gem 'simple_form'

Installation

rails generate simple_form:install

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const powerOfTwo = (num) => {
	let pot = Math.pow(2, Math.ceil(Math.log2(num))) - num;

	if (pot === 0) {
		return "true";
	} else {
		return "false";
	}
};

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function SnakeCase(str) {
	const regex = /\W+/g;

	for (char in str) {
		let newStr = str.toLowerCase().replace(regex, "_");
		return newStr;
	}
}

console.log(SnakeCase("This*is a Great-Night"));

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PSQL

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)

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# All AWS C9 envments
https://eu-central-1.console.aws.amazon.com/cloud9/home?region=us-east-1

# Instance management
https://console.aws.amazon.com/ec2/home?region=eu-central-1#Instances:sort=instanceId

# Create AWS C9 environment
https://eu-central-1.console.aws.amazon.com/cloud9/home/create

Setting - set tabs to 2

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# A Django project's configuration lives in settings.py.

DATABASES = {
    'default': {
        'ENGINE': 'django.db.backends.postgresql',
        'NAME': 'dbname',
    }
}

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Big-O Notation Exercises

What is the worst-case time complexity for the following algorithms?

#1

function wordOccurrence(word, phrase){
  let result = 0
  const array  = phrase.split(' ')