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TL;DR: If using :group => :some_field you might want to :order => 'NULL'.

According to the man

By default, MySQL sorts all GROUP BY col1, col2, ... queries as if you ...

In a nutshell, use screen

Why?
Sometimes we are concerned that if our connection gets closed, the process we are running will close too.

The processes or login sessions you establish through screen don't go away. You can resume your...

1. Add to the end your .bash_profile export PATH="./vendor/bundle/bin:$PATH"
2. Also add alias bi="bundle install --path vendor/bundle --binstubs=vendor/bundle/bin"
3. Then to bundle install next time just use bi

Now no more ```...

As you know, time zones make stuff a bit more difficult but are necessary.

A time-zoned record is converted to UTC using to_s(:db) to be st...

Given:

datetime = DateTime.now
date = datetime.to_date #or Date.today

will assert:

datetime.is_a? Date == true
datetime.is_a? DateTime == true
datetime.instance_of? Date == false
datetime.instance_of? DateTime == true

In case y...

It's a good pratice to chain several named scopes like:

Property.listable.for_2_or_more_guests.best_10_properties

Now, to make the lesson more valuable let's assume the following code:

Property.scoped(:conditions => "foo = 2").scoped(...

When simply checking equality or truthiness then
Instead of:
it "should have role set to admin" do
@user.role.should eql('admin')
end

it "should be valid" do
  @user.valid?.should be_true
end

Do:
it { @user.role.shou...

Regularly, but at least before merging your feature branches, rebase them to get rid of "fix typo" and "wip" commits.

Getting rid of unnecessary commits

Let's say you do a git rebase -i HEAD~~~~ and have this...

Wether you modify an existing named scope or add a new one, or when you write a new query, make sure you have the proper indices.

This particularly applies if you're going to run non-trivial queries of course (admin backends, analytics, etc).

##...

One of the main source of bugs and complexity in the code is when a functional method (that we expect to return a value) return different values under different circumstances.

For example, we ruby programmers have a bad habit of returning nil fro...