kafaichoi

1. Why do they call it a relational database? Relational database are usually consisted of different tables which are related to other table by foreign key. And Foreign key in one table is the primary key of a record in another table. We can easily make a query base on different criteria on different table by joining the table.

2.What is SQL? SQL stands for Structured Query Language. It is a Domain Specific Language for managing data in RDBMS

3. There are two predominant views into a relational database. What are they, and how are they different? They are the data and schema views. Data view displays like a spreadsheet. A schema view descripts the column names and the value type of each column.

4. In a table, what do we call the column that serves as the main identifier for a row of data? We're looking for the general database term, not the column name.

kafaichoi

Quiz: Lesson 3

1. What's the difference between rendering and redirecting? What's the impact with regards to instance variables, view templates?
They both complete a request but redirect will tell the client (browser) to send a brand-new request to a new URL. Therefore, no instance variable from previous action triggering the redirect will be available to the redirected view template . For rendering, the instance variable from the action will be avaiable for the view template being rendered. 


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

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

kafaichoi

<p>This is deprecated, in future versions you may need to <code>bundle binstub rails</code> to work around a system/bundle conflict.<br>
/home/kafai/.rvm/gems/ruby-2.0.0-p481/gems/paratrooper-0.0.1/lib/paratrooper.rb:1:in <code>require': cannot load such file -- heroku (LoadError)<br>
    from /home/kafai/.rvm/gems/ruby-2.0.0-p481/gems/paratrooper-0.0.1/lib/paratrooper.rb:1:in</code>'<br>
    from /home/kafai/.rvm/gems/ruby-2.0.0-p481@global/gems/bundler-1.6.2/lib/bundler/runtime.rb:76:in <code>require'<br>
    from /home/kafai/.rvm/gems/ruby-2.0.0-p481@global/gems/bundler-1.6.2/lib/bundler/runtime.rb:76:in</code>block (2 levels) in require'<br>
    from /home/kafai/.rvm/gems/ruby-2.0.0-p481@global/gems/bundler-1.6.2/lib/bundler/runtime.rb:72:in <code>each'<br>
    from /home/kafai/.rvm/gems/ruby-2.0.0-p481@global/gems/bundler-1.6.2/lib/bundler/runtime.rb:72:in</code>block in require'<br>
    from /home/kafai/.rvm/gems/ruby-2.0.0-p481@global/gems/bundler-1.6.2/lib/bundler/runtime.rb:61:in <code>each'<br>
   

kafaichoi

curl -v -H "Accept: application/json" -H "Content-type: application/json" -X POST -d ' {"user":{"fullname":"Bob Chan","email":"bob@email.com","password":"password"}}'  http://localhost:3000/api/users

kafaichoi

Register in HockeyApp
-Android
  1. cordova build --release android
  2. keytool -genkey -v -keystore my-release-key.keystore -alias alias_name -keyalg RSA -keysize 2048 -validity 10000
  3. jarsigner -verbose -sigalg SHA1withRSA -digestalg SHA1 -keystore my-release-key.keystore HelloWorld-release-unsigned.apk alias_name
  4. zipalign -v 4 HelloWorld-release-unsigned.apk HelloWorld.apk
  5. upload apk file to HockeyApp
  
-IOS
  1. cordova build --release ios

kafaichoi

CREATE TABLE shake_magnitudes (
event_id int,
user_id int,
recorded_at timestamp,
magnitude float,
PRIMARY KEY (event_id, user_id, recorded_at)
)
WITH CLUSTERING ORDER BY (user_id ASC, recorded_at ASC);

kafaichoi

:e.	:edit .	at current working directory
:sp.	:split .	in split at current working directory
:vs.	:vsplit .	in vertical split at current working directory
:E	:Explore	at directory of current file
:Se	:Sexplore	in split at directory of current file
:Vex	:Vexplore	in vertical split at directory of current file

%	create a new file
d	create a new directory
R	rename the file/directory under the cursor

kafaichoi

#!/bin/bash
# installing erlang on ubuntu's

VERSION="R15B01"

sudo apt-get install build-essential libncurses5-dev openssl libssl-dev

sudo mkdir -p /opt/erlang/
curl -O https://raw.github.com/spawngrid/kerl/master/kerl && chmod a+x kerl
sudo mv kerl /opt/erlang/

kafaichoi

TL;DR

Install Postgres 9.5, and then:

sudo pg_dropcluster 9.5 main --stop
sudo pg_upgradecluster 9.3 main
sudo pg_dropcluster 9.3 main

kafaichoi

Great Program https://www.freecodecamp.com/

Get your hand dirty https://www.codecademy.com/learn/javascript

Advice for self-learning http://blog.42la.bs/advice-for-self-taught-programmer/

Command Line