helderasmoreira / til

A collection of TIL snippets

TIL

A repository of TIL snippets on small things I learn day to day across a variety of languages and technologies.

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Categories

• CSS
• Database
• Infrastructure
• Life
• Rails
• Regex
• REST
• Ruby
• Security

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CSS

• Emails should use inline CSS
• Breakpoints are not as useful in emails

Database

• MySQL does not support partial indexes
• MySQL does case insensitive string comparison by default

Infrastructure

• Manage Heroku environment variables

Life

• Always be learning

Rails

• Rails will perform caching on all SQL queries
• Deep munging your params
• Find or create with additional attributes

Regex

• Easy way to look for duplicate lines in a sorted file

REST

• 201 Created should respond just with an header

Ruby

• Memoization can be tricky when false or nil
• Converting strings to integers is tricky business

Security

• Constant time comparison helps prevent attacks
• Stress your code and put it under siege
• Cookie's SameSite options can be confusing