tykurtz

GROKKING NOTES

I liked the way Grokking the coding interview organized problems into learnable patterns. However, the course is expensive and the majority of the time the problems are copy-pasted from leetcode. As the explanations on leetcode are usually just as good, the course really boils down to being a glorified curated list of leetcode problems.

So below I made a list of leetcode problems that are as close to grokking problems as possible.

Pattern: Sliding Window

• https://leetcode.com/problems/maximum-subarray/ # Close enough
• https://leetcode.com/problems/minimum-size-subarray-sum/

rosswd

Learning Relational Database Design and SQL

Learn SQL (interactive)

• SQLBolt
• SQLZoo
• GalaXQL
• Mode SQL Tutorial
• Datacamp: Intro to SQL for Data Science
• Codecademy Learn SQL
• Select Star SQL

ian-whitestone

Presto Specific

• Don’t SELECT *, Specify explicit column names (columnar store)
• Avoid large JOINs (filter each table first)
  • In PRESTO tables are joined in the order they are listed!!
  • Join small tables earlier in the plan and leave larger fact tables to the end
  • Avoid cross joins or 1 to many joins as these can degrade performance
• Order by and group by take time
  • only use order by in subqueries if it is really necessary
• When using GROUP BY, order the columns by the highest cardinality (that is, most number of unique values) to the lowest.

avoidik

Top 10 Examples of AWS CLI Query

List Volumes showing attachment using Dictionary Notation

$ aws ec2 describe-volumes \
  --query 'Volumes[*].{ID:VolumeId,InstanceId:Attachments[0].InstanceId,AZ:AvailabilityZone,Size:Size}'
[
    {
        "InstanceId": "i-a071c394",

Tset-Noitamotua

"++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++"
"                                                                              "
"                       __   _ _ _ __ ___  _ __ ___                            "
"                       \ \ / / | '_ ` _ \| '__/ __|                           "
"                        \ V /| | | | | | | | | (__                            "
"                         \_/ |_|_| |_| |_|_|  \___|                           "
"                                                                              "
"                                                                              "
"++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++"

vasanthk

System Design Cheatsheet

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

Basic Steps

1. 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?

fredbenenson

layout	title	description	tags
default	SQL Style Guide	A guide to writing clean, clear, and consistent SQL.	data process

Purpose

haisum

sed -i '/<pattern>/s/^/#/g' file #comment
sed -i '/<pattern>/s/^#//g' file #uncomment

shawnrice

#!/bin/sh

# This is a skeleton of a bash daemon. To use for yourself, just set the
# daemonName variable and then enter in the commands to run in the doCommands
# function. Modify the variables just below to fit your preference.

daemonName="DAEMON-NAME"

pidDir="."
pidFile="$pidDir/$daemonName.pid"