mikehaertl

Learn you a Haskell - In a nutshell

This is a summary of the "Learn You A Haskell" online book under http://learnyouahaskell.com/chapters.

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1. Introduction

• Haskell is a functional programming language.

alvareztech

import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JOptionPane;
import javax.swing.JTextField;

/**
 * Clase Ventana

jcasimir

Transactions

As your business logic gets complex you may need to implement transactions. The classic example is a bank funds transfer from account A to account B. If the withdrawal from account A fails then the deposit to account B should either never take place or be rolled back.

Basics

All the complexity is handled by ActiveRecord::Transactions. Any model class or instance has a method named .transaction. When called and passed a block, that block will be executed inside a database transaction. If there's an exception raised, the transaction will automatically be rolled back.

Example

amatellanes

/* Useful celery config.

app = Celery('tasks',
             broker='redis://localhost:6379',
             backend='redis://localhost:6379')

app.conf.update(
    CELERY_TASK_RESULT_EXPIRES=3600,
    CELERY_QUEUES=(
        Queue('default', routing_key='tasks.#'),

hofmannsven

MySQL

Getting started

• http://www.sqlteaching.com/
• https://www.codecademy.com/learn/learn-sql
• https://www.codecademy.com/catalog/language/sql

Related tutorials

• MySQL-CLI
• Analyzing Business Metrics