stungkit

System Design Cheatsheet

Picking the right architecture = Picking the right battles + Managing trade-offs

Basic Steps

Clarify and agree on the scope of the system

User cases (description of sequences of events that, taken together, lead to a system doing something useful)
- Who is going to use it?
- How are they going to use it?

SQL languages

DDL is short name of Data Definition Language, which deals with database schemas and descriptions, of how the data should reside in the database.

DML is short name of Data Manipulation Language which deals with data manipulation, and includes most common SQL statements such SELECT, INSERT, UPDATE, DELETE etc, and it is used to store, modify, retrieve, delete and update data in database.

DCL is short name of Data Control Language which includes commands such as GRANT, and mostly concerned with rights, permissions and other controls of the database system.

Datatypes

Text types

how to leverage oracle's temping offers

free tier limits

The limits of the free tier say that you can create up to 4 instances.

x2 x86 instances (2core/1g)
x2 ampere instances (with 4core/24g spread between them)
200GB total boot volume space across all intances (minimum of 50G per instance)

create your account

how to leverage oracle's temping offers

free tier limits

The limits of the free tier say that you can create up to 4 instances.

x2 x86 instances (2core/1g)
x2 ampere instances (with 4core/24g spread between them)
200GB total boot volume space across all intances (minimum of 50G per instance)

	from gensim.models import Word2Vec

	# Load pretrained model (since intermediate data is not included, the model cannot be refined with additional data)
	model = Word2Vec.load_word2vec_format('GoogleNews-vectors-negative300.bin', binary=True, norm_only=True)

	dog = model['dog']
	print(dog.shape)
	print(dog[:10])

	# Deal with an out of dictionary word: Михаил (Michail)

	# See https://codeship.com/documentation/docker/browser-testing/
	FROM myapp:base

	# We need wget to set up the PPA and xvfb to have a virtual screen and unzip to install the Chromedriver
	RUN apt-get install -y wget xvfb unzip

	# Set up the Chrome PPA
	RUN wget -q -O - https://dl-ssl.google.com/linux/linux_signing_key.pub \| apt-key add -
	RUN echo "deb http://dl.google.com/linux/chrome/deb/ stable main" >> /etc/apt/sources.list.d/google.list

	# Repo: someuser/myframework
	# Fork: superteam/myframework

	# Track:
	git clone https://github.com/superteam/myframework.git
	cd myframework
	git remote add upstream https://github.com/someuser/myframework.git

	# Update:
	git fetch upstream

Service	Type	Storage	Limitations
Amazon DynamoDB	⚠️ Proprietary NoSQL	25 GB	⚠️ Payment method required
Amazon RDS	⚠️ Proprietary RDBMS		⚠️ Only free for 1 year
Azure SQL Database	MS SQL Server		⚠️ Only free for 1 year
👉 Clever Cloud	PostgreSQL, MySQL, MongoDB, Redis	256 MB (PostgreSQL)	Max 5 connections (PostgreSQL)

	# define base image as python slim-buster.
	FROM python:3.7-slim-buster as base

	## start builder stage.

	# this is the first stage of the build.
	# it will install all requirements.
	FROM base as builder

	# install all packages for chromedriver: https://gist.github.com/varyonic/dea40abcf3dd891d204ef235c6e8dd79

	/*
	This is based on an idea for building a table of contents on top of
	React Markdown using a custom renderer. The original conversation is at

	https://github.com/remarkjs/react-markdown/issues/48
	*/

	import React from "react";

	import ReactMarkdown from "react-markdown";