Ecto is a domain specific language for writing queries and interacting with databases in Elixir. Here is an example:
# In your config/config.exs file
config :my_app, Repo,
database: "ecto_simple",
username: "postgres",
password: "postgres",
hostname: "localhost"
# In your application code
defmodule Repo do
use Ecto.Repo,
otp_app: :my_app,
adapter: Ecto.Adapters.Postgres
end
defmodule Weather do
use Ecto.Model
schema "weather" do
field :city # Defaults to type :string
field :temp_lo, :integer
field :temp_hi, :integer
field :prcp, :float, default: 0.0
end
end
defmodule Simple do
import Ecto.Query
def sample_query do
query = from w in Weather,
where: w.prcp > 0 or is_nil(w.prcp),
select: w
Repo.all(query)
end
endSee the online documentation or run the sample application for more information.
Add Ecto as a dependency in your mix.exs file. If you are using PostgreSQL, you will also need the library that Ecto's PostgreSQL adapter is using.
defp deps do
[{:postgrex, ">= 0.0.0"},
{:ecto, "~> 0.5"}]
endYou should also update your applications list to include both projects:
def application do
[applications: [:postgrex, :ecto]]
endAfter you are done, run mix deps.get in your shell to fetch the dependencies.
Ecto is on the bleeding edge of Elixir so the latest master build is most likely needed, see Elixir's README on how to build from source.
To contribute you need to compile Ecto from source and test it:
$ git clone https://github.com/elixir-lang/ecto.git
$ cd ecto
$ mix test
If you are contributing to the Postgres adapter you need to run the integration tests for the adapter (it is a good idea to run the integration tests even if you are not contributing to the adapter). You need a Postgres user with username postgres and password postgres or with trust authentication. To run the tests the MIX_ENV environment variable needs to be set to pg when running the tests. To run only the integration tests: MIX_ENV=pg mix test or to run all tests: MIX_ENV=all mix test.
Copyright 2012 Plataformatec
Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at
http://www.apache.org/licenses/LICENSE-2.0
Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.