1.Migration is a set of database instructions written in Ruby. The objective of migration is to change database state from one to another.

True

False

2.Both of the following commands are equivalent in Rails 5.0+:

rake db:migrate

and

rails db:migrate

True

False

3.Assuming there is a model User with attributes of name and occupation, the create method call will create and save a new record into the database as follows:

user = User.create(name: "David", occupation: "Code Artist")

Alternatively the following code will also create a user record but not save it into the database:

user = User.new user.name = "David" user.occupation = "Code Artist"

Which of the following is the correct syntax for committing the user record to the database after the above code?

user.commit

user.done

user.save

None of the choices

user.persist

4.The following model code creates a Student model and maps it to a students table in the database:

class Students < Application Record end

True

False

5.Active Record allows you to validate the state of a model before it gets written into the database. One such method is save. What is the difference between the user.save! and user.savemethods?

None of the choices

user.save! is stricter in that it raises the exception ActiveRecord::RecordInvalid if validation fails.

Both user.save and user.save! are the same functionally

user.save is stricter in that it raises the exception ActiveRecord::RecordInvalid if validation fails.