z3niths

# Optimized MySQL configuration for cPanel servers by Kani Baspinar - Updated June 2016
#
# The settings provided below are a starting point for a 24GB RAM server with 8 CPU cores.
# If you have less or more resources available you MUST adjust accordingly to save CPU, RAM and disk I/O usage.
# To fine tune these settings for your system, use MySQL DB diagnostics tools like:
# Test your configuration ; https://launchpad.net/mysql-tuning-primer
# or
# http://blog.mysqltuner.com/download/
# Note that if there is NO comment beside a setting, then you don't need to adjust it.
#

z3niths

To help you with the process of converting a MySQL app to PostgreSQL, I collected a list of differences between MySQL and PostgreSQL (PG).

Important changes:

* Strings are quoted with '...' or with $token$...$token$. Single-quotes are escaped with single-quotes.
* Identifiers are folded to lowercase, unless they are quoted with "..." which makes them case-sensitive
* The max identifier length is 63
* There are some system columns that cannot be used as an identifier (probably not a problem)
* Expressions are evaluated in arbitrary order, so WHERE x > 0 AND y/x > 1.5 can lead to a division by zero and has to be replaced with WHERE CASE WHEN y > 0 THEN y/x > 1.5 ELSE FALSE END
* SELECT CASE WHEN x > 0 THEN x ELSE 1/0 END would still lead to a division by zero because the constant 1/0 is evaluated even before the query starts

z3niths

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)

z3niths

#include <stdio.h>
#include <stdint.h>
#include <stdlib.h>
#include <string.h>

// yousif, namazso, can1357, defcon42
namespace packet
{
	constexpr size_t be_xor_key = 0xd774f59d;

z3niths

#include <stdio.h>
#include <stdint.h>
#include <stdlib.h>
#include <string.h>

// yousif, namazso, can1357, defcon42
namespace packet
{
	constexpr size_t be_xor_key = 0xd774f59d;

z3niths

const webpack = require('webpack');
const CopyWebpackPlugin = require('copy-webpack-plugin');
const HtmlWebpackPlugin = require('html-webpack-plugin');
const CleanWebpackPlugin = require('clean-webpack-plugin');
const ManifestPlugin = require('webpack-manifest-plugin');
const MiniCssExtractPlugin = require('mini-css-extract-plugin');
const WebpackNotifierPlugin = require('webpack-notifier');
const TailwindCss = require('tailwindcss');
const AutoPrefixer = require('autoprefixer');
const path = require('path');

z3niths

{
   "ABNA":{
      "BIC":"ABNANL2A",
      "bank_name":"ABN AMRO BANK N.V"
   },
   "AEGO":{
      "BIC":"AEGONL2U",
      "bank_name":"AEGON BANK NV"
   },
   "ANDL":{

z3niths

Latency numbers every programmer should know

L1 cache reference ......................... 0.5 ns
Branch mispredict ............................ 5 ns
L2 cache reference ........................... 7 ns
Mutex lock/unlock ........................... 25 ns
Main memory reference ...................... 100 ns             
Compress 1K bytes with Zippy ............. 3,000 ns  =   3 µs
Send 2K bytes over 1 Gbps network ....... 20,000 ns  =  20 µs
SSD random read ........................ 150,000 ns  = 150 µs

Read 1 MB sequentially from memory ..... 250,000 ns = 250 µs