# ActiveRecord::UUID

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Override migration methods to support UUID columns without having to be explicit about it.

What this gem will do for you:

- When creating new tables, will set the `id` column as `uuid`.
- When creating associations with `t.belongs_to`, `t.references` or `add_reference`, will set the column type as `uuid`.

## Installation

Add this line to your application's Gemfile:

```ruby
gem "ar-uuid"
```

And then execute:

    $ bundle

Or install it yourself as:

    $ gem install ar-uuid

## Usage

There's no setup. Just adding the gem to your Gemfile is enough. When you create a new table, the `id` column will be defined as `uuid`. This is also true for references.

```ruby
create_table :users
add_reference :posts, :users

create_table :posts do |t|
  t.belongs_to :user
  # or
  t.references :user
end
```

If you need a serial column, AR's PostgreSQL supports the `bigserial` column type.

```ruby
create_table :users do |t|
  t.column :position, :bigserial, null: false
end
```

### Disadvantages

There is one big disadvantage on using uuid identifiers: you can't use  methods like `ActiveRecord::FinderMethods::InstanceMethods#first` and `ActiveRecord::FinderMethods::InstanceMethods#last`, since they are scoped to the sequential id.

Instead of `.first`, you can use [ActiveRecord::FinderMethods::InstanceMethods#take](https://github.com/rails/rails/blob/f52354ad1d15120dcc5284714bee7ee3f052986c/activerecord/lib/active_record/relation/finder_methods.rb#L104), which will use the order implemented by the database.

There's no alternative to `.last`.

## Development

After checking out the repo, run `bin/setup` to install dependencies. Then, run `bin/console` for an interactive prompt that will allow you to experiment.
4
To install this gem onto your local machine, run `bundle exec rake install`. To release a new version, update the version number in `version.rb`, and then run `bundle exec rake release` to create a git tag for the version, push git commits and tags, and push the `.gem` file to [rubygems.org](https://rubygems.org).

## Contributing

1. Fork it ( https://github.com/fnando/ar-uuid/fork )
2. Create your feature branch (`git checkout -b my-new-feature`)
3. Commit your changes (`git commit -am 'Add some feature'`)
4. Push to the branch (`git push origin my-new-feature`)
5. Create a new Pull Request