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#!/usr/bin/env python3

import argparse
import json
import re
import boto3
from botocore.config import Config

try:
    from collections.abc import Mapping

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Copyright 2020 Glia Inc.

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 copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER D

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PostgreSQL changes from 9.5 to 11

Full list of changes: https://why-upgrade.depesz.com/show?from=9.5.21&to=11.7

Highlights

• Parallel queries
• Declarative partitioning
• Covering indexes
• Improved performance

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defmodule Friends.Application do
  # See https://hexdocs.pm/elixir/Application.html
  # for more information on OTP Applications
  @moduledoc false

  use Application

  def start(_type, _args) do
    # List all child processes to be supervised
    children = [

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class FibonacciCalculator
  def initialize
  end

  def run
    number = ARGV.first

    puts "Fibonacci number for N=#{number}: #{fib(number.to_i)}"
  end

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Taken from here

Deploy without downtime

We deploy without downtime when we can to avoid user frustration. It's pretty rare that we can't.

There's a great talk/slideshow on this, but no convenient reference that we're aware of – hence this document.

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def f(q,n)
  if(n==nil)
  return null;
  end
  l=0; h=ln(q)-1;d=l<=h;
  while d
    x=(l+h)/2;v=q[x]
    if v>n then h=x-1
    elsif v<n then l=x+1
    else return v

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WITH table_scans as (
    SELECT relid,
        tables.idx_scan + tables.seq_scan as all_scans,
        ( tables.n_tup_ins + tables.n_tup_upd + tables.n_tup_del ) as writes,
                pg_relation_size(relid) as table_size
        FROM pg_stat_user_tables as tables
),
all_writes as (
    SELECT sum(writes) as total_writes
    FROM table_scans

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./extract.sh | wc -l

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require 'enumerator'
require 'ox'

module Ox
  class PushParser
    DEFAULT_BUFSIZE = 4096

    def initialize(handler, options = {}, &blk)
      @buf = ''
      @generator = Enumerator.new(&blk)