Groupdate

The simplest way to group by:

• day
• week
• month
• day of the week
• hour of the day
• and more (complete list at bottom)

🎉 Time zones supported!! the best part

🍰 Get the entire series - the other best part

Works with Rails 3.0+

Supports PostgreSQL and MySQL

💘 Goes hand in hand with Chartkick

Usage

User.group_by_day(:created_at).count
# {
#   2013-04-16 00:00:00 UTC => 50,
#   2013-04-17 00:00:00 UTC => 100,
#   2013-04-18 00:00:00 UTC => 34
# }

Task.group_by_month(:updated_at).count
# {
#   2013-02-01 00:00:00 UTC => 84,
#   2013-03-01 00:00:00 UTC => 23,
#   2013-04-01 00:00:00 UTC => 44
# }

Goal.group_by_year(:accomplished_at).count
# {
#   2011-01-01 00:00:00 UTC => 7,
#   2012-01-01 00:00:00 UTC => 11,
#   2013-01-01 00:00:00 UTC => 3
# }

The default time zone is Time.zone. Pass a time zone as the second argument.

User.group_by_week(:created_at, "Pacific Time (US & Canada)").count
# {
#   2013-03-03 08:00:00 UTC => 80,
#   2013-03-10 08:00:00 UTC => 70,
#   2013-03-17 07:00:00 UTC => 54
# }

# equivalently
time_zone = ActiveSupport::TimeZone["Pacific Time (US & Canada)"]
User.group_by_week(:created_at, time_zone).count

Note: Weeks start on Sunday.

You can also group by the day of the week or hour of the day.

# day of the week
User.group_by_day_of_week(:created_at).count
# {
#   0 => 54, # Sunday
#   1 => 2,  # Monday
#   ...
#   6 => 3   # Saturday
# }

# hour of the day
User.group_by_hour_of_day(:created_at, "Pacific Time (US & Canada)").count
# {
#   0 => 34,
#   1 => 61,
#   ...
#   23 => 12
# }

You can order results with:

User.group_by_day(:created_at).order("day asc").count

User.group_by_week(:created_at).order("week desc").count

User.group_by_hour_of_day(:created_at).order("hour_of_day asc").count

Use it with anywhere you can use group.

Task.completed.group_by_hour(:completed_at).average(:priority)

Go nuts!

Request.where(page: "/home").group_by_minute(:started_at).maximum(:request_time)

Show me the series 💰

You have two users - one created on May 2 and one on May 5.

User.group_by_day(:created_at).count
# {
#   2013-05-02 00:00:00 UTC => 1,
#   2013-05-05 00:00:00 UTC => 1
# }

Awesome, but you want to see the first week of May. Pass a range as the third argument.

# pretend today is May 7
time_range = 6.days.ago..Time.now

User.group_by_day(:created_at, Time.zone, time_range).count
# {
#   2013-05-01 00:00:00 UTC => 0,
#   2013-05-02 00:00:00 UTC => 1,
#   2013-05-03 00:00:00 UTC => 0,
#   2013-05-04 00:00:00 UTC => 0,
#   2013-05-05 00:00:00 UTC => 1,
#   2013-05-06 00:00:00 UTC => 0,
#   2013-05-07 00:00:00 UTC => 0
# }

User.group_by_day_of_week(:created_at, Time.zone, time_range).count
# {
#   0 => 0,
#   1 => 1,
#   2 => 0,
#   3 => 0,
#   4 => 1,
#   5 => 0,
#   6 => 0
# }

Results are returned in ascending order, so no need to sort.

Also, this form of the method returns a Groupdate::Series instead of an ActiveRecord::Relation. ActiveRecord::Relation method calls (like where and joins) should come before this.

Installation

Add this line to your application's Gemfile:

gem 'groupdate'

For MySQL

Time zone support must be installed on the server.

mysql_tzinfo_to_sql /usr/share/zoneinfo | mysql -u root mysql

For JRuby

Use the master version of your JDBC adapter. You will get incorrect results for versions before this commit.

# postgresql
gem "activerecord-jdbcpostgresql-adapter", :github => "jruby/activerecord-jdbc-adapter"

# mysql
gem "activerecord-jdbcmysql-adapter", :github => "jruby/activerecord-jdbc-adapter"

Complete list

group_by_?

• second
• minute
• hour
• day
• week
• month
• year
• hour_of_day
• day_of_week

Note

activerecord <= 4.0.0.beta1 and the pg gem returns String objects instead of Time objects. This is fixed on activerecord master

User.group_by_day(:created_at).count

# mysql2
# pg and activerecord master
{2013-04-22 00:00:00 UTC => 1} # Time object

# pg and activerecord <= 4.0.0.beta1
{"2013-04-22 00:00:00+00" => 1} # String

Another data type inconsistency

User.group_by_day_of_week(:created_at).count

# mysql2
{0 => 1, 4 => 1} # Integer

# pg and activerecord <= 4.0.0.beta1
{"0" => 1, "4" => 1} # String

# pg and activerecord master
{0.0 => 1, 4.0 => 1} # Float

These are not a result of groupdate (and unfortunately cannot be fixed by groupdate)

History

View the changelog

Groupdate follows Semantic Versioning

Contributing

1. Fork it
2. Create your feature branch (git checkout -b my-new-feature)
3. Commit your changes (git commit -am 'Add some feature')
4. Push to the branch (git push origin my-new-feature)
5. Create new Pull Request