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WAL-G PITR

This gist summarises a way to simulate point-in-time recovery (PITR) using WAL-G. Most of the material is adapted from Creston's tutorial.

Setup

First we initialize a database cluster

pg_ctl init -D cluster

PostgreSQL Page Checksum Protection

This gist summarises a way to create corrupted databases. Most of the material is adapted from Luca's Article.

Setup the database

Create and start the server with data checksums enabled

initdb -k -D cluster

This is a sample program that tests output on a panicking go program based on different GOTRACEBACK settings. There are several levels that control the amount of output generated - none, single, all, system - each with it's own aliases. More information can be found at https://golang.org/pkg/runtime/.

env GOTRACEBACK=none go run main.go

This should give the same output as env GOTRACEBACK=0 go run main.go

panic: f3
exit status 2

	from bs4 import BeautifulSoup
	import requests
	import datetime
	import logging
	import csv

	def setLogger():
	logging.basicConfig(level=logging.INFO,
	format='%(asctime)s - %(levelname)s - %(message)s',
	filename='logs_file',

	import numpy as np
	import pandas as pd

	#### creating dataframes, adding and dropping columns

	df = pd.DataFrame(np.arange(1,10).reshape(3,3),['A','B','C'],['w','x','y'])
	df.columns = ['W','X','Y'] # change column names
	df['Z']=df['X']+df['Y'] # new column with values X+Y
	df['XX']=df.apply(lambda row: row['X']*2, axis=1) # new column with values twice of column X
	df['YY']=1 # new column of ones

	#!/bin/bash
	for filename in *.xlsm; do
	cp "$filename" "backup/$(basename "$filename" .xlsm) $(date +'%Y%m%d%H%M%S').xlsm"
	done

	// this is a file that puts together all redigo examples for convenience
	// (see https://godoc.org/github.com/gomodule/redigo/redis#pkg-examples)
	//
	// start by ensuring that redis is running on port 6379 (`redis-server`)
	// uncomment the main method as needed, and run the script (`go run main.go`)
	package main

	import (
	"fmt"
	"github.com/gomodule/redigo/redis"

	class TreeNode:
	def __init__(self, val):
	self.val = val
	self.left = None
	self.right = None

	def buildTree(arr):
	nodes = [TreeNode(val) for val in arr]
	for i in range(len(nodes)):
	left, right = (i+1)2-1, (i+1)2

	package join

	import (
	"fmt"
	"strings"
	"testing"
	)

	var (
	testData = []string{"a", "b", "c", "d", "e"}

	git rebase -i --root
	# change verbs for relevant commits to `edit`
	while [ $? -eq 0 ]; do git commit --amend --reset-author --no-edit --allow-empty --date="$(git log -n 1 --format=%ad)" && git rebase --continue; done