how to learn ruby on rails

Here simply add a few validations, non-empty, minimum length, uniqueModifying a modelModify the App/models/post.rb file as follows:Class Post At this time to run the service, modify/New model, when nothing is filled, can not be submitted, nor error.What's the reason?Because you didn't show the error message.Modify viewsModify the App/views/posts/new.html.erb file as follows:That is, addFor App/views/posts/edit.html.erb.Running the serviceRails S-b 192.168.xxx.xxx-p 3000, add a record, do not fil

everything is set up, it is time to install Rails. To start, open terminal and type in: gem install rails This process may take a while, be patient with it. Once it finishes you will have Ruby on Rails installed on your droplet. -- Source to network. For Ruby on

Introduction: Ruby on Rails is just one aspect of making Ruby very powerful, just as EJB is part of the Java Enterprise platform. Andrew Glover reveals what Java developers can do with Ruby. Before I begin this article, I need to clarify a few things. First, it's not an article about

About Ruby on Rails Ruby on Rails is an application stack that provides developers with a framework to quickly create a variety of Web applications. ruby on Rails does take a little while to install on a virtual server, but luckil

The first two sections of this series have already covered how to configure the Ruby on Rails development environment, and now it's time to get to the point!Part1. Pre-development Preparation The main task of this time is to develop the first rails program. In particular, this time I chose a (PAAs development platform), which is the Cloud 9 platform describ

Keywords: Ruby on Rails, instantrails, windows, getting started, tutorial I always wanted to try Ruby on Rails, but I was not familiar with Apache and MySQL, and I was not confident in setting up the rails environment. So I never started. After learning about instantrails,

I have always been very interested in Ruby on Rails. I want to see something that has been praised by many people, but I have been working on windows development, it is still a headache to build the development environment of Ruby on Rails, Which is why Ruby on

1. Auxiliary methods2. StringEnter "IRB" into the ruby command-line development environment, and the controller starts by executing "rails console" on the command line.(1) String connection>>"foo"+"bar"="foobar" (2) Interpolation by special syntax #{}>>first_name="Amy" ="Amy">>" #{first_name} Sun"+"Amy Sun "(3) The difference between a single-quote string and a double-quote string: Single-quote strings the

Brief introduction Today's applications need to interoperate not only with browser-based clients, but with other applications as well. For interoperability, Web applications typically provide a Web service API. The Web services API provides remote access to applications through a network, such as the Internet. Until recently, the Web services API had also been integrated with heavy, complex, SOAP-based Web services, which had little merit and would take a long time to implement. The

non-lookup SQL statements ActiveRecord::Base.connection.execute "ALTER TABLE some_table CHANGE COLUMN..." Most mode operations, such as adding or deleting columns, can be completed using the built-in Rails method. However, if necessary, you can also use the ability to execute arbitrary SQL code. Conclusion Like all the frameworks, Ruby on Rails may also suffer

role:apple> enter It again:apple> shall the new role be a superuser? (y/n) n> shall the new role being allowed to create databases? (y/n) n> shall the new role being allowed to create more new roles? (y/n) n> Password:your-postgres-user-passwordThen, create a database user that tests the application as the owner of the database. While we can use Rake to create a database, we want to use PostgreSQL, so let's learn basic PostgreSQL management. Use the

and access the methods and variables in your Rail application. This tutorial explains how to configure and use RJB in a Rails application. Goal In this tutorial, you will learn how to: Download, compile, and install RJB Set up RJB to access the shared Java library Load Legacy Java code into a Rails application and acces

shown in Listing 13.Listing 13. Customizing the output of SQL with ActiveRecord Programmer, Avg. age:18.010, Avg. accidents:9 System Administrator, Avg. age:22.720, Avg. accidents:8 This is, of course, the simplest example. You can imagine how you can extend the SQL in this example to a somewhat complex SQL statement. You can also use the Activerecord::base.connection.execute method to run other types of SQL statements, such as ALTER TABLE statements, as shown in Listing 14.Lis

with J2EE be beneficial to rails? Absolutely not. J2EE is a set standard with many fixed implementations, and, most importantly, it is a proven technology. I suggest you download a copy of rails and study it yourself. Many of the available tutorials are introductory. These tutorials allow you to start using rails immediately. Again, I cannot guarantee that you w

Use Ruby on Rails to quickly develop web applications. Ruby on Rails is impacting the entire Web development field. Let's first understand the underlying technologies: Ruby is a free, simple, intuitive, scalable, portable, and interpreted scripting language for fast and simp

Ruby on Rails is shaking the whole Web development landscape. Let us first understand the underlying technology: Ruby is a free, simple, intuitive, extensible, portable, and interpreted scripting language for fast and simple object-oriented programming. Like Perl, it supports many of the features of working with text files and performing system administration ta

-related work. Memory problems are the primary cause of Slow Ruby applications. The 80-20 rule for Rails performance optimization is like this: the 80% increase is due to the memory optimization, and the remaining 20% is another factor. Why is memory consumption so important? Because the more memory you allocate, the more work Ruby GC (Ruby's garbage collection m