Hi! I am Benito Serna, a software developer from México, that has been learning/working with rails since 2010. Here I try to share what I know about it.

Most recent posts

• Tool to run the examples for the 5 ways to fetch the latest-n-of-each record

  A common cause of n+1 queries is fetching the “latest-N-of-each” record on a list of records.

  Some examples of this problem are trying to get…

  Read more

• How to test that an email was sent on a unit/micro test

  There are different practices, that I know, to test that an email was sent in Rails…

  Read more

All posts by topic

actionmailer activerecord activestorage capybara deployment design doubles form objects heroku javascript mexico n+1 performance rails ruby scopes stimulus testing

• actionmailer

  • Jul 12 2021 How to test that an email was sent on a unit/micro test
  • Jul 2 2021 How to test that an email was sent on a feature spec
  • Jan 27 2021 How to attach an active storage file to an email

• activerecord

  • Jul 22 2021 Tool to run the examples for the 5 ways to fetch the latest-n-of-each record
  • Jun 29 2021 Guide to name scopes based on column types
  • May 27 2021 Extracting domain knowledge from a query method
  • May 14 2021 "Please help me with my n+1 problem..."
  • May 6 2021 Building a DateTime range to query for the records created a "week before"
  • Feb 22 2021 Quiz to practice the difference between preload, includes or eager_load
  • Feb 16 2021 Code to run the examples for preload, includes or eager_load
  • Feb 4 2021 Examples to learn the difference between preload, includes or eager_load
  • Jan 19 2021 When is better to use preload or eager_load vs includes?
  • Jan 7 2021 What is the difference between includes, preload, eager_load and joins in ActiveRecord?
  • Dec 23 2020 5 ways to fetch the latest-N-of-each record on Rails
  • Dec 8 2020 10 Examples to learn when your ActiveRecord query will be executed
  • Nov 20 2020 Why Active Record seems to ignore your "includes" and runs a query for each record?
  • Nov 2 2020 Benchmarks for the fixes to the latest-comment n+1 problem
  • Oct 20 2020 5 ways to fix the latest-comment n+1 problem
  • Sep 30 2020 Association with default order, to fix the latest-comment n+1 problem

• activestorage

  • Jan 27 2021 How to attach an active storage file to an email

• capybara

  • Jul 2 2021 How to test that an email was sent on a feature spec
  • May 3 2021 How to test a PDF download with capybara
  • Apr 20 2021 A simple way of testing a CSV download with capybara
  • Mar 24 2021 Capybara cheatsheet
  • Mar 17 2021 Custom capybara matchers with compound expectations

• deployment

  • Jun 22 2021 List of alternatives to heroku
  • Jun 14 2021 Guide to justify the heroku's price to your boss or clients
  • Jun 8 2021 List of questions to check if heroku is really expensive for your project

• design

  • May 27 2021 Extracting domain knowledge from a query method
  • Oct 14 2020 You can create a model for that multi-record form
  • Oct 6 2020 Create a new controller for the hidden abstraction and reduce conditionals

• doubles

  • Jul 12 2021 How to test that an email was sent on a unit/micro test

• form objects

  • Oct 14 2020 You can create a model for that multi-record form

• heroku

  • Jun 22 2021 List of alternatives to heroku
  • Jun 14 2021 Guide to justify the heroku's price to your boss or clients
  • Jun 8 2021 List of questions to check if heroku is really expensive for your project

• javascript

  • Apr 19 2021 A "read-more" behavior truncating with rails truncate helper and Stimulus.js
  • Apr 3 2021 A "read-more" behavior truncating by number of lines with css line-clamp and Stimulus.js
  • Apr 2 2021 A "read-more" behavior truncating by number of lines with custom javascript and Stimulus.js

• mexico

  • May 5 2021 How to read the noCertificado from a CSD for a mexican CFDI

• n+1

  • Jul 22 2021 Tool to run the examples for the 5 ways to fetch the latest-n-of-each record
  • May 14 2021 "Please help me with my n+1 problem..."
  • Mar 1 2021 Tools to help you detect n+1 queries
  • Feb 22 2021 Quiz to practice the difference between preload, includes or eager_load
  • Feb 16 2021 Code to run the examples for preload, includes or eager_load
  • Feb 4 2021 Examples to learn the difference between preload, includes or eager_load
  • Jan 19 2021 When is better to use preload or eager_load vs includes?
  • Jan 7 2021 What is the difference between includes, preload, eager_load and joins in ActiveRecord?
  • Dec 23 2020 5 ways to fetch the latest-N-of-each record on Rails
  • Dec 8 2020 10 Examples to learn when your ActiveRecord query will be executed
  • Nov 20 2020 Why Active Record seems to ignore your "includes" and runs a query for each record?
  • Nov 19 2020 PDF with the benchmarks for the fixes to the latest-comment n+1 problem
  • Nov 14 2020 Tool to run the benchmark for fixes for the latest-comment n+1 queries problem
  • Nov 13 2020 Cheatsheet to help you decide which fix for the last-comment n+1 problem is the best for you
  • Nov 10 2020 Tool to run the fixes for the latest-comment n+1 queries problem
  • Nov 2 2020 Benchmarks for the fixes to the latest-comment n+1 problem
  • Oct 20 2020 5 ways to fix the latest-comment n+1 problem
  • Sep 30 2020 Association with default order, to fix the latest-comment n+1 problem

• performance

  • Mar 1 2021 Tools to help you detect n+1 queries

• rails

  • Jul 22 2021 Tool to run the examples for the 5 ways to fetch the latest-n-of-each record
  • Jun 29 2021 Guide to name scopes based on column types
  • May 27 2021 Extracting domain knowledge from a query method
  • May 14 2021 "Please help me with my n+1 problem..."
  • May 6 2021 Building a DateTime range to query for the records created a "week before"
  • May 3 2021 How to test a PDF download with capybara
  • Apr 20 2021 A simple way of testing a CSV download with capybara
  • Apr 19 2021 A "read-more" behavior truncating with rails truncate helper and Stimulus.js
  • Apr 3 2021 A "read-more" behavior truncating by number of lines with css line-clamp and Stimulus.js
  • Apr 2 2021 A "read-more" behavior truncating by number of lines with custom javascript and Stimulus.js
  • Mar 24 2021 Capybara cheatsheet
  • Mar 17 2021 Custom capybara matchers with compound expectations
  • Mar 1 2021 Tools to help you detect n+1 queries
  • Feb 22 2021 Quiz to practice the difference between preload, includes or eager_load
  • Feb 16 2021 Code to run the examples for preload, includes or eager_load
  • Feb 4 2021 Examples to learn the difference between preload, includes or eager_load
  • Jan 27 2021 How to attach an active storage file to an email
  • Jan 19 2021 When is better to use preload or eager_load vs includes?
  • Jan 7 2021 What is the difference between includes, preload, eager_load and joins in ActiveRecord?
  • Dec 23 2020 5 ways to fetch the latest-N-of-each record on Rails
  • Dec 8 2020 10 Examples to learn when your ActiveRecord query will be executed
  • Nov 20 2020 Why Active Record seems to ignore your "includes" and runs a query for each record?
  • Nov 19 2020 PDF with the benchmarks for the fixes to the latest-comment n+1 problem
  • Nov 14 2020 Tool to run the benchmark for fixes for the latest-comment n+1 queries problem
  • Nov 13 2020 Cheatsheet to help you decide which fix for the last-comment n+1 problem is the best for you
  • Nov 10 2020 Tool to run the fixes for the latest-comment n+1 queries problem
  • Nov 2 2020 Benchmarks for the fixes to the latest-comment n+1 problem
  • Oct 20 2020 5 ways to fix the latest-comment n+1 problem
  • Oct 14 2020 You can create a model for that multi-record form
  • Oct 6 2020 Create a new controller for the hidden abstraction and reduce conditionals
  • Sep 30 2020 Association with default order, to fix the latest-comment n+1 problem

• ruby

  • Jul 22 2021 Tool to run the examples for the 5 ways to fetch the latest-n-of-each record
  • Jun 29 2021 Guide to name scopes based on column types
  • May 27 2021 Extracting domain knowledge from a query method
  • May 14 2021 "Please help me with my n+1 problem..."
  • May 6 2021 Building a DateTime range to query for the records created a "week before"
  • May 5 2021 How to read the noCertificado from a CSD for a mexican CFDI
  • Mar 24 2021 Capybara cheatsheet
  • Mar 17 2021 Custom capybara matchers with compound expectations
  • Mar 1 2021 Tools to help you detect n+1 queries
  • Feb 22 2021 Quiz to practice the difference between preload, includes or eager_load
  • Feb 17 2021 Which specs would you prefer for this presentation object?
  • Feb 16 2021 Code to run the examples for preload, includes or eager_load
  • Feb 4 2021 Examples to learn the difference between preload, includes or eager_load
  • Jan 19 2021 When is better to use preload or eager_load vs includes?
  • Jan 7 2021 What is the difference between includes, preload, eager_load and joins in ActiveRecord?
  • Dec 23 2020 5 ways to fetch the latest-N-of-each record on Rails
  • Dec 8 2020 10 Examples to learn when your ActiveRecord query will be executed
  • Nov 20 2020 Why Active Record seems to ignore your "includes" and runs a query for each record?
  • Nov 19 2020 PDF with the benchmarks for the fixes to the latest-comment n+1 problem
  • Nov 14 2020 Tool to run the benchmark for fixes for the latest-comment n+1 queries problem
  • Nov 13 2020 Cheatsheet to help you decide which fix for the last-comment n+1 problem is the best for you
  • Nov 10 2020 Tool to run the fixes for the latest-comment n+1 queries problem
  • Nov 2 2020 Benchmarks for the fixes to the latest-comment n+1 problem
  • Oct 20 2020 5 ways to fix the latest-comment n+1 problem
  • Oct 14 2020 You can create a model for that multi-record form
  • Oct 6 2020 Create a new controller for the hidden abstraction and reduce conditionals
  • Sep 30 2020 Association with default order, to fix the latest-comment n+1 problem

• scopes

  • Jun 29 2021 Guide to name scopes based on column types

• stimulus

  • Apr 19 2021 A "read-more" behavior truncating with rails truncate helper and Stimulus.js
  • Apr 3 2021 A "read-more" behavior truncating by number of lines with css line-clamp and Stimulus.js
  • Apr 2 2021 A "read-more" behavior truncating by number of lines with custom javascript and Stimulus.js

• testing

  • Jul 12 2021 How to test that an email was sent on a unit/micro test
  • Jul 2 2021 How to test that an email was sent on a feature spec
  • May 3 2021 How to test a PDF download with capybara
  • Apr 20 2021 A simple way of testing a CSV download with capybara
  • Mar 24 2021 Capybara cheatsheet
  • Mar 17 2021 Custom capybara matchers with compound expectations
  • Feb 17 2021 Which specs would you prefer for this presentation object?