#!/usr/bin/env ruby
#
# A standalone example of the aggregate method
require 'rubygems'
require 'dm-core'
require 'dm-migrations'
require 'dm-aggregates'


# setup the logger
DataMapper::Logger.new($stdout, :debug)

# connect to the DB
DataMapper.setup(:default, 'sqlite3::memory:')

class Example
  include DataMapper::Resource

  # properties
  property :id, Serial
  property :total, Float
  property :name, String
end

DataMapper.finalize.auto_migrate!

10.times do |n|
  Example.create(:name => (n % 2), :total => n)
end

p Example.aggregate(:name, :total.sum)


__END__


 ~ (0.000102) SELECT sqlite_version(*)
 ~ (0.000206) DROP TABLE IF EXISTS "examples"
 ~ (0.000024) PRAGMA table_info("examples")
 ~ (0.000496) CREATE TABLE "examples" ("id" INTEGER NOT NULL PRIMARY KEY AUTOINCREMENT, "total" FLOAT, "name" VARCHAR(50))
 ~ (0.000119) INSERT INTO "examples" ("total", "name") VALUES (0.0, '0')
 ~ (0.000107) INSERT INTO "examples" ("total", "name") VALUES (1.0, '1')
 ~ (0.000090) INSERT INTO "examples" ("total", "name") VALUES (2.0, '0')
 ~ (0.000103) INSERT INTO "examples" ("total", "name") VALUES (3.0, '1')
 ~ (0.000093) INSERT INTO "examples" ("total", "name") VALUES (4.0, '0')
 ~ (0.000088) INSERT INTO "examples" ("total", "name") VALUES (5.0, '1')
 ~ (0.000089) INSERT INTO "examples" ("total", "name") VALUES (6.0, '0')
 ~ (0.000098) INSERT INTO "examples" ("total", "name") VALUES (7.0, '1')
 ~ (0.000090) INSERT INTO "examples" ("total", "name") VALUES (8.0, '0')
 ~ (0.000089) INSERT INTO "examples" ("total", "name") VALUES (9.0, '1')
 ~ (0.000100) SELECT "name", SUM("total") FROM "examples" GROUP BY "name" ORDER BY "name"
[["0", 20.0], ["1", 25.0]]