Does rails need a database?

Rails comes with built-in support for SQLite, which is a lightweight serverless database application. While a busy production environment may overload SQLite, it works well for development and testing. Rails defaults to using a SQLite database when creating a new project, but you can always change it later.

What is Ruby SQL?

Next Chapter: Using Non-Ruby Programs With Ruby. SQL, short for Structured Query Language is a programming language for querying and managing databases. It has its own syntax and different database systems – including Microsoft Access, MySQL, PostgreSQL, and SQLite – all have their own variations of SQL.

What is eager loading Rails?

Eager loading is a way to find objects of a certain class and a number of named associations. Here I share my thoughts on using it with Rails. Above will also returns the multiple objects for the same user if there will be more than 1 records for address for the user, so following modification will be required.

What does rake db setup do?

rake db:migrate makes changes to the existing schema. Its like creating versions of schema. db:migrate will look in db/migrate/ for any ruby files and execute the migrations that aren’t run yet starting with the oldest.

How does rails connect to MySQL database?

Connecting MySQL with Ruby on Rails

1. Step 1: Install MySQL in the System.
2. Step2: Create a Database in the Local.
3. Step3: Create a New Rails App using Mysql.
4. Step4: Change the Database.yml with your Mysql Database Name that we Created Earlier.

How you can run Rails application without creating databases?

Using Rails Without a Database

1. Open /samples/hello/config/environment. rb file in a text editor.
2. Remove the pound character (#) in front of line 21 to uncomment it so that it reads as: config.frameworks -= [ :active_record, :active_resource, :action_mailer ]
3. Save the file.

What are scopes in Rails?

Scopes are custom queries that you define inside your Rails models with the scope method. Every scope takes two arguments: A name, which you use to call this scope in your code. A lambda, which implements the query.

What is difference between lazy loading and eager loading?

While lazy loading delays the initialization of a resource, eager loading initializes or loads a resource as soon as the code is executed. Eager loading also involves pre-loading related entities referenced by a resource.