gistfile1.txt

#!/usr/bin/env ruby
#
# A one file test to show count
require 'rubygems'
require 'dm-core'
require 'dm-aggregates'

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

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

class Thing
  include DataMapper::Resource

  # properties
  property :id, Serial

  has n, :widgets
end

class Widget
  include DataMapper::Resource

  # properties
  property :id, Serial

  belongs_to :thing
end


DataMapper.auto_migrate!

10.times do
  thing = Thing.create
  thing.widgets.create
end

@t = Thing.first

puts "-"*80

Thing.all.each do |thing|
  puts thing.widgets.count
end



__END__

 ~ (0.000180) SELECT sqlite_version(*)
 ~ (0.000134) DROP TABLE IF EXISTS "things"
 ~ (0.000017) DROP TABLE IF EXISTS "widgets"
 ~ (0.000019) PRAGMA table_info("things")
 ~ (0.000366) CREATE TABLE "things" ("id" INTEGER NOT NULL PRIMARY KEY AUTOINCREMENT)
 ~ (0.000012) PRAGMA table_info("widgets")
 ~ (0.000116) CREATE TABLE "widgets" ("id" INTEGER NOT NULL PRIMARY KEY AUTOINCREMENT, "thing_id" INTEGER NOT NULL)
 ~ (0.000128) CREATE INDEX "index_widgets_thing" ON "widgets" ("thing_id")
 ~ (0.000034) INSERT INTO "things" DEFAULT VALUES
 ~ (0.000030) INSERT INTO "things" DEFAULT VALUES
 ~ (0.000035) INSERT INTO "things" DEFAULT VALUES
 ~ (0.000032) INSERT INTO "things" DEFAULT VALUES
 ~ (0.000033) INSERT INTO "things" DEFAULT VALUES
 ~ (0.000033) INSERT INTO "things" DEFAULT VALUES
 ~ (0.000032) INSERT INTO "things" DEFAULT VALUES
 ~ (0.000036) INSERT INTO "things" DEFAULT VALUES
 ~ (0.000032) INSERT INTO "things" DEFAULT VALUES
 ~ (0.000036) INSERT INTO "things" DEFAULT VALUES
 ~ (0.000042) SELECT "id" FROM "things" ORDER BY "id" LIMIT 1
 ~ (0.000056) INSERT INTO "widgets" ("thing_id") VALUES (1)
 ~ (0.000045) INSERT INTO "widgets" ("thing_id") VALUES (1)
 ~ (0.000040) INSERT INTO "widgets" ("thing_id") VALUES (1)
 ~ (0.000040) INSERT INTO "widgets" ("thing_id") VALUES (1)
 ~ (0.000042) INSERT INTO "widgets" ("thing_id") VALUES (1)
 ~ (0.000041) INSERT INTO "widgets" ("thing_id") VALUES (1)
 ~ (0.000040) INSERT INTO "widgets" ("thing_id") VALUES (1)
 ~ (0.000040) INSERT INTO "widgets" ("thing_id") VALUES (1)
 ~ (0.000041) INSERT INTO "widgets" ("thing_id") VALUES (1)
 ~ (0.000040) INSERT INTO "widgets" ("thing_id") VALUES (1)
--------------------------------------------------------------------------------
 ~ (0.000033) SELECT "id" FROM "things" ORDER BY "id"
 ~ (0.000071) SELECT "id", "thing_id" FROM "widgets" WHERE "thing_id" IN (1, 2, 3, 4, 5, 6, 7, 8, 9, 10) ORDER BY "id"
 ~ (0.000026) SELECT "id" FROM "things" ORDER BY "id"
 ~ (0.000079) SELECT "id", "thing_id" FROM "widgets" WHERE "thing_id" IN (1, 2, 3, 4, 5, 6, 7, 8, 9, 10) ORDER BY "id"
 ~ (0.000087) SELECT COUNT(*) FROM "widgets" WHERE "thing_id" = 1
1
 ~ (0.000031) SELECT COUNT(*) FROM "widgets" WHERE "thing_id" = 2
1
 ~ (0.000029) SELECT COUNT(*) FROM "widgets" WHERE "thing_id" = 3
1
 ~ (0.000030) SELECT COUNT(*) FROM "widgets" WHERE "thing_id" = 4
1
 ~ (0.000029) SELECT COUNT(*) FROM "widgets" WHERE "thing_id" = 5
1
 ~ (0.000030) SELECT COUNT(*) FROM "widgets" WHERE "thing_id" = 6
1
 ~ (0.000030) SELECT COUNT(*) FROM "widgets" WHERE "thing_id" = 7
1
 ~ (0.000038) SELECT COUNT(*) FROM "widgets" WHERE "thing_id" = 8
1
 ~ (0.000032) SELECT COUNT(*) FROM "widgets" WHERE "thing_id" = 9
1
 ~ (0.000029) SELECT COUNT(*) FROM "widgets" WHERE "thing_id" = 10
1