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, Sample.Repo,
adapter: Ecto.Adapters.Postgres,
database: "ecto_simple",
username: "postgres",
password: "postgres"
# In your application code
defmodule Sample.Repo do
use Ecto.Repo,
otp_app: :my_app
end
defmodule Sample.Weather do
use Ecto.Schema
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 Sample.App do
import Ecto.Query
alias Sample.Weather
alias Sample.Repo
def keyword_query do
query = from w in Weather,
where: w.prcp > 0 or is_nil(w.prcp),
select: w
Repo.all(query)
end
def pipe_query do
Weather
|> where(city: "Kraków")
|> order_by(:temp_lo)
|> limit(10)
|> Repo.all
end
end
See the online documentation or run the sample application for more information.
You need to add both Ecto and the database adapter as a dependency to your mix.exs
file. The supported databases and their adapters are:
Database | Ecto Adapter | Dependency | Ecto 2.0 compatible? |
---|---|---|---|
PostgreSQL | Ecto.Adapters.Postgres | postgrex | Yes |
MySQL | Ecto.Adapters.MySQL | mariaex | No |
MSSQL | Tds.Ecto | tds_ecto | No |
SQLite3 | Sqlite.Ecto | sqlite_ecto | No |
MongoDB | Mongo.Ecto | mongodb_ecto | No |
For example, if you want to use PostgreSQL, add to your mix.exs
file:
defp deps do
[{:postgrex, ">= 0.0.0"},
{:ecto, "~> 1.1"}]
end
and update your applications list to include both projects:
def application do
[applications: [:postgrex, :ecto]]
end
Then run mix deps.get
in your shell to fetch the dependencies. If you want to use another database, just choose the proper dependency from the table above.
Finally, in the repository configuration, you will need to specify the adapter:
respective to the chosen dependency. For PostgreSQL it is:
config :my_app, Repo,
adapter: Ecto.Adapters.Postgres,
...
We are currently looking for contributions to add support for other SQL databases and folks interested in exploring non-relational databases too.
For overall guidelines, please see CONTRIBUTING.md.
Clone the repo and fetch its dependencies:
$ git clone https://github.com/elixir-lang/ecto.git
$ cd ecto
$ mix deps.get
$ mix test
Besides the unit tests above, it is recommended to run the adapter integration tests too:
# Run only PostgreSQL tests (version of PostgreSQL must be >= 9.4 to support jsonb)
MIX_ENV=pg mix test
# Run all tests (unit and all adapters/pools)
mix test.all
$ MIX_ENV=docs mix docs
Copyright (c) 2012, Plataformatec.
Ecto source code is licensed under the Apache 2 License.