sinsoku

class LeapYear
  LEAP_MSG = "%d is a leap year"
  NOT_LEAP_MSG = "%d is not a leap year"

  class << self
    def leap?(n)
      n % 400 == 0 || (n % 4 == 0 && n % 100 != 0)
    end

    def msg(n)

sinsoku

SELECT
  b.id,
  b.brandname,
  COUNT(*)
FROM
  gamelist g
INNER JOIN brandlist b
  ON g.brandname= b.id
GROUP BY
  b.id

sinsoku

SELECT
  to_char(g.sellday, 'YYYY') "year",
  g.sellday,
  g.gamename,
  g.median
FROM gamelist g
INNER JOIN (
  SELECT
    to_char(g2.sellday, 'YYYY') "year",
    MAX(g2.median) "median"

sinsoku

SELECT
  c.name,
  COUNT(*)
FROM createrlist c
INNER JOIN shokushu s
  ON c.id = s.creater
INNER JOIN gamelist g
  ON g.id = s.game
INNER JOIN userreview_with_tag uwt
  ON g.id = uwt.game

sinsoku

SELECT
  to_char(g.sellday, 'YYYY') "year",
  SUM(CASE a.title WHEN 'Nscripter' THEN 1 ELSE 0 END) "Nscripter",
  SUM(CASE a.title WHEN '吉里吉里' THEN 1 ELSE 0 END) "吉里吉里"
FROM attributelist a
INNER JOIN attributegroupsboolean ag
  ON a.id = ag.attribute
INNER JOIN gamelist g
  ON g.id = ag.game
WHERE

sinsoku

SELECT
  g.sellday,
  g.gamename,
  COUNT(u.game) "count"
FROM gamelist g
INNER JOIN userreview u
  ON g.id = u.game
WHERE
  g.sellday > to_date('2000', 'YYYY')
GROUP BY

sinsoku

describe User do
  let(:user) { FactoryGirl.create :user }
  before { user.fizz_buzz! }

  # 実行結果で副作用があるので、それのテスト
  it { expect(user.name).to eq 'fizz_buzz' }
  it { expect(user.age).to be_nil }
  # has_many の関連先が消えている事の確認
  it { expect(user.friendships).to be_blank }
end

sinsoku

protocol ExternalAccount {}
extension ExternalAccount {
    func save() {
        print("PATCH http://api.external.com/user")
    }
}

protocol DataBaseAccount {}
extension DataBaseAccount {
    func save() {

sinsoku

protocol StringConvertible {}
extension StringConvertible {
    func toString() -> String {
        return "StringConvertible: \(self)"
    }
}

protocol StringType {}
extension StringType {
    func toString() -> String {

sinsoku

class User {}

// Twitter
protocol Twitter {
//    var username: String { get }
}
extension Twitter {
    var username: String {
        get { return "tryswiftconf" }
    }