TILs - Fueling Curiosity, One Insight at a Time

At Codemancers, we believe every day is an opportunity to grow. This section is where our team shares bite-sized discoveries, technical breakthroughs and fascinating nuggets of wisdom we've stumbled upon in our work.

Published
Author
user-image
Nived Hari
System Analyst
Instead of manually checking if a key exists in a hash, you can just say:


Code

counts = Hash.new(0)


Now whenever you do:


Code

counts[:apple] += 1


Ruby will assume counts[:apple] starts at 0, so no errors — just clean, readable code.

#ruby
Published
Author
user-image
Syed Sibtain
System Analyst
Traits are reusable groups of attributes that we can apply to factories conditionally.
They help avoid duplication and let us customise factories based on different test scenarios.


We can define a trait inside a factory block using the trait keyword


Code

FactoryBot.define do
  factory :user do
    name { "John Doe" }

    trait :admin do
      role { "admin" }
    end

    trait :with_profile_picture do
      after(:build) do |user|
        user.profile_picture.attach(
          io: File.open(Rails.root.join('spec/fixtures/files/test.jpg')),
          filename: 'test.jpg',
          content_type: 'image/jpeg'
        )
      end
    end
  end
end


And then we can use them in our specs. And traits can override any attribute defined in the factory


Code

create(:user, :with_profile_picture)
create(:user, :admin, :with_profile_picture)


#CU6U0R822 #rspec
Published
Author
user-image
Syed Sibtain
System Analyst
define_singleton_method dynamically adds a method to a single object instance without modifying the class itself. This is useful when you need custom behaviour for an individual object at runtime.

It only modifies the behaviour of a single object in memory at runtime. It does not persist any changes to the database or schema.


Code

user = User.new(name: "Sibtain")

user.define_singleton_method(:greet) do
  "Hello, my name is #{name}!"
end

puts user.greet # => "Hello, my name is Sibtain"


#CU6U0R822
Published
Author
user-image
Nived Hari
System Analyst
PostgreSQL's jsonb type stores structured JSON data efficiently. Unlike json, it's binary-optimized, supports indexing, and queries faster.
🔹 Why Use jsonb?
• Stores structured data in a single column.
• Faster queries (no reparsing needed).
• Supports indexing for quick lookups.
• Flexible schema—great for dynamic data.
• Allows key-value updates without rewriting the whole object.
• Removes duplicate keys automatically.
jsonb gives you NoSQL flexibility with SQL power! 🚀

#postgres
Published
Author
user-image
Puneeth kumar
System Analyst
Aliasing in Ruby
Aliasing in Ruby helps to eliminate code repetition by providing an alternative name for an existing method, allowing it to be called in different ways without duplicating the logic.
For example,

Code

module QuestionsHelper
  def can_modify_question?(question)
    !question.survey.has_answers?
  end

  alias_method :can_edit_question?, :can_modify_question?
  alias_method :can_delete_question?, :can_modify_question?
end


#ruby #aliasing
Published
Author
user-image
Nived Hari
System Analyst
Turbo provides a built-in way to show a loading state on form submission using the turbo_submits_with attribute! 🚀
Instead of manually handling the button's disabled state or adding a spinner, you can simply use:


Code

<%= form.submit t("post.create"), 
  data: { turbo_submits_with: t('loading.saving') } %>


• When the form is submitted, Turbo automatically
replaces the button text with the value provided in turbo_submits_with (e.g., "Saving...").

• Button is also disabled until the request completes.
• Once the request completes, the button reverts to its original text.
No extra JavaScript needed! 🎉

This is a great way to enhance UX with minimal effort. #Rails #Turbo #TIL
Published
Author
user-image
Satya
while using form.number_field in rails if we enter a floating point value eg: 23.45 then browser default validation kicks in syaing: Please enter a valid value. The two nearest valid values are 23 & 24 .
In order to allow the floating point value we can add form.number_field, step: "0.01" . Then we can add upto two decimal point vlaue.

#CU6U0R822 #form-tag-helper
Published
Author
user-image
Satya
to terminate google chrome sessions -> pkill -9 "Google Chrome" .
#terminate-session
Published
Author
user-image
Satya
Ruby Heredoc Syntax & Rails .squish method:
• Bad - Regular heredoc (<<) keeps all whitespace

Code

query = <<SQL
    SELECT *
    FROM users
SQL
# Result: "    SELECT *\n    FROM users\n"


• Good - Squiggly heredoc (<<) removes leading whitespace

```
query = <<SQL
SELECT *
FROM users
SQL
# Result: "SELECT \nFROM users\n"
```

• *Best - Rails .squish removes all extra whitespace/newlines

Code

query = <<~SQL.squish
    SELECT *
    FROM   users
    WHERE  active = true
SQL
# Result: "SELECT * FROM users WHERE active = true"


#ruby-heredoc #rails-squish
Published
Author
user-image
Puneeth kumar
System Analyst
TimescaleDB

When working with time series data like stock prices, website traffic, or error logs, the volume of data grows rapidly over time. In traditional relational databases like PostgreSQL and SQL, this can lead to slower query performance as the dataset becomes larger.

One alternative is to use NoSQL databases, but they come with their own challenges, such as lack of strong ACID compliance, complex querying, and difficulties in handling structured relational data.

TimescaleDB, which is built on top of PostgreSQL, offers a powerful solution by introducing hypertables - a special type of table optimised for time series data. Hypertables enable faster read and write operations, automatic partitioning, and efficient data compression. Additionally, TimescaleDB provides advanced analytical functions, making it easier to perform complex queries for reporting, trend analysis, and forecasting. This makes it a great choice for applications that require efficient storage and analysis of large-scale time series data.

#databases #time_series_data #timescale_db #postgres

Showing 7 to 9 of 83 results

Ready to Build Something Amazing?

Codemancers can bring your vision to life and help you achieve your goals

Let's Talk