Create Records

This guide shows you how to create new records in the database.

Create with new + save

Create an instance and save separately:

user = User.new("John", "[e-mail]")

if user.save
  puts "Created user #{user.id}"
else
  puts "Failed: #{user.errors.map(&.message).join(", ")}"
end

Create with save!

Use save! to raise an exception on failure:

user = User.new("John", "[e-mail]")
user.save!  # Raises if validation fails
puts "Created user #{user.id}"

Create in One Step

Use create to instantiate and save:

user = User.create(name: "John", email: "[e-mail]")

if user.persisted?
  puts "Created user #{user.id}"
else
  puts "Failed to create"
end

Create! in One Step

Use create! to raise on failure:

user = User.create!(
  name: "John",
  email: "[e-mail]",
  age: 30
)
puts "Created user #{user.id}"

Create Multiple Records

users = ["Alice", "Bob", "Charlie"].map do |name|
  User.create!(
    name: name,
    email: "#{name.downcase}@example.com"
  )
end

puts "Created #{users.size} users"

Create with Relationships

user = User.create!(name: "John", email: "[e-mail]")

post = Post.create!(
  title: "My First Post",
  body: "Hello world!",
  user_id: user.id.not_nil!
)

puts "Created post for user #{user.name}"

Create with Default Values

Set defaults in your model:

struct User
  property status : String = "pending"
  property role : String = "user"
end

user = User.create!(name: "John", email: "[e-mail]")
user.status  # => "pending"
user.role    # => "user"

Create with Timestamp

Timestamps are set automatically if configured:

user = User.create!(name: "John", email: "[e-mail]")
user.created_at  # => 2024-01-15 10:30:00 UTC
user.updated_at  # => 2024-01-15 10:30:00 UTC

Handle Validation Errors

user = User.new("", "invalid-email")

unless user.save
  user.errors.each do |error|
    puts "#{error.field}: #{error.message}"
  end
end

Verify Creation

user = User.create!(name: "John", email: "[e-mail]")

user.id.nil?        # => false (has ID now)
user.persisted?     # => true
user.new_record?    # => false

Related

• Update Records

• Delete Records

• Use Transactions