kangkyu

1. why do they call it a relational database?
because they have join and association between tables.

(solution: because the tables within the database are associated with each other. This association can be created with primary and foreign keys and various syntax.)

2. what is SQL?
language used in all database systems

(solution: SQL stands for "structured query language" and it is used to manage operations of a relational database.)

kangkyu

lesson 2 Quiz

1. Name all the 7 or 8 routes exposed by the resources keyword in the routes.rb file. Also name the 4 named routes, and how the request is routed to the controller/action.

	name_routes	action	

GET	posts_path 	posts#index		
GET	post_path	posts#show
GET	new_post_path	posts#new
POST			posts#create	

kangkyu

print "the first number: "
a = gets.chomp
print "operator: "
operator = gets.chomp
print "the second number: "
b = gets.chomp

answer = case operator.ord
  when 43 then a.to_i + b.to_i
  when 45 then a.to_i - b.to_i

kangkyu

    - if flash[:notice]
      = content_tag(:div, class: ["alert", "alert-info", "alert-dismissible"], role: "alert", id: "notice") do
        = content_tag(:button, class: "close", type: "button", "data-dismiss"=> "alert") do
          = content_tag(:span, escape_once("×"), "aria-hidden"=> "true")
          = content_tag(:span, "Close", class: "sr-only")
        = flash[:notice]

kangkyu

  - if @task.errors.any?
    = content_tag(:div, class: ["alert", "alert-danger", "alert-dismissible"], role: "alert", id: "error-explanation") do
      = content_tag(:button, class: "close", type: "button", "data-dismiss"=> "alert") do
        = content_tag(:span, escape_once("×"), "aria-hidden"=> "true")
        = content_tag(:span, "Close", class: "sr-only")
      %p= pluralize(@task.errors.count, "error") + " prohibited this user from being saved"
      %ul
        - @task.errors.full_messages.each do |msg|
          %li= msg

kangkyu

(0..9).to_a + ('a'..'z').to_a + ('A'..'Z').to_a + %w(! @ # $ % ^ & * < > ?)
a = _
a.shuffle.pop(9).join

kangkyu

<form action="http://google.com">
    <input type="submit" value="Go to Google">
</form>

<a href="http://google.com">Go to Google</a>

kangkyu

git clone https://github.com/kangkyu/list-of-hamburger-restaurants.git
cd list-of-hamburger-restaurants
echo "# list-of-hamburger-restaurants" >> README.md
git add README.md
git commit -m "first commit"
git push -u origin master

kangkyu

##Quiz: Lesson 3 Solutions

####1. What's the difference between rendering and redirecting? What's the impact with regards to instance variables, view templates?

Rendering displays a view template that accesses the instance variables available in that action. Therefore, instance variables must be declared in that action before the render will work. Redirecting will send a new request to the browser based on the route path that was provided. In this case, the instance variables in that action are not related to the redirected view.

####2. If I need to display a message on the view template, and I'm redirecting, what's the easiest way to accomplish this?

You can use flash, which saves the message with a session. The message will be displayed on your next action and will be removed after that. flash[:message] = 'Your account was created.' redirect_to :back

kangkyu

Use guard-shell gem.

# terminal (at exercism/ruby/)
gem install guard guard-shell
guard init shell

# Guardfile