Median and percentile for Active Record, Mongoid, arrays, and hashes
Supports:
- PostgreSQL
- SQLite
- MariaDB
- MySQL (with an extension)
- SQL Server
- MongoDB
🔥 Uses native functions for blazing performance
Add this line to your application’s Gemfile:
gem "active_median"For MySQL, also follow these instructions.
Median
Item.median(:price)Percentile
Request.percentile(:response_time, 0.95)Works with grouping, too
Order.group(:store_id).median(:total)Median
[1, 2, 3].medianPercentile
[1, 2, 3].percentile(0.95)You can also pass a block
{a: 1, b: 2, c: 3}.median { |k, v| v }MySQL requires the PERCENTILE_CONT function from udf_infusion. To install it, do:
git clone https://github.com/infusion/udf_infusion.git
cd udf_infusion
./configure --enable-functions="percentile_cont"
make
sudo make install
mysql <options> < load.sqlImprove performance with SQLite with an extension. Download percentile.c and follow the instructions for compiling loadable extensions for your platform.
On Linux, use:
gcc -g -fPIC -shared -lsqlite3 percentile.c -o percentile.soOn Mac, use:
gcc -g -fPIC -dynamiclib -L/usr/local/opt/sqlite/lib -lsqlite3 percentile.c -o percentile.dylibTo load it in Rails, create an initializer with:
db = ActiveRecord::Base.connection.raw_connection
db.enable_load_extension(1)
db.load_extension("percentile.so") # or percentile.dylib
db.enable_load_extension(0)Everyone is encouraged to help improve this project. Here are a few ways you can help:
- Report bugs
- Fix bugs and submit pull requests
- Write, clarify, or fix documentation
- Suggest or add new features
To get started with development:
git clone https://github.com/ankane/active_median.git
cd active_median
bundle install
# Postgres
createdb active_median_test
bundle exec rake test
# SQLite
ADAPTER=sqlite3 BUNDLE_GEMFILE=gemfiles/sqlite3.gemfile bundle exec rake test
# MariaDB and MySQL (for MySQL, install the extension first)
mysqladmin create active_median_test
ADAPTER=mysql2 BUNDLE_GEMFILE=gemfiles/mysql2.gemfile bundle exec rake test
# SQL Server
docker run -e 'ACCEPT_EULA=Y' -e 'SA_PASSWORD=YourStrong!Passw0rd' -p 1433:1433 -d mcr.microsoft.com/mssql/server:2022-latest
docker exec -it <container-id> /opt/mssql-tools/bin/sqlcmd -S localhost -U SA -P YourStrong\!Passw0rd -Q "CREATE DATABASE active_median_test"
ADAPTER=sqlserver BUNDLE_GEMFILE=gemfiles/sqlserver.gemfile bundle exec rake test
# MongoDB
BUNDLE_GEMFILE=gemfiles/mongoid7.gemfile bundle exec rake test
