Avram

Database ORM built for the Lucky Framework written in Crystal. Supporting PostgreSQL 12+ and based off principals of Elixir Ecto and Rails ActiveRecord.

Why Avram?

The name comes from Henriette Avram.

Henriette Davidson Avram (October 7, 1919 – April 22, 2006) was a computer programmer and systems analyst who developed the MARC format (Machine Readable Cataloging), the international data standard for bibliographic and holdings information in libraries.

Installation

Add this to your application's shard.yml:

dependencies:
  avram:
    github: luckyframework/avram

Usage

require "avram"

# Define your database
class AppDatabase < Avram::Database
end

AppDatabase.configure do |settings|
  settings.credentials = Avram::Credentials.new(
    database: "my_app_development",
    username: "postgres",
    hostname: "localhost",
    password: "password",
    port: 5432,
  )
end

# Configure Avram to use your database
Avram.configure do |settings|
  settings.database_to_migrate = AppDatabase

  # When `true`, allow lazy loading (N+1).
  # If `false` raise an error if you forget to preload associations
  settings.lazy_load_enabled = true
  settings.query_cache_enabled = false
end

# Create your read-only model
class Person < Avram::Model
  def self.database : Avram::Database.class
    AppDatabase
  end

  table :people do
    column name : String
    column age : Int32
    column programmer : Bool = true
  end
end

# Insert a new record
Person::SaveOperation.create!(name: "Henriette Davidson Avram", age: 86)
# Query for a record
person = Person::BaseQuery.new.name.ilike("%avram")
person.programmer? #=> true