Ecto is a toolkit for data mapping and language integrated query for Elixir. Here is an example:
# In your config/config.exs file
config :my_app, ecto_repos: [Sample.Repo]
config :my_app, Sample.Repo,
database: "ecto_simple",
username: "postgres",
password: "postgres",
hostname: "localhost",
port: "5432"
# In your application code
defmodule Sample.Repo do
use Ecto.Repo,
otp_app: :my_app,
adapter: Ecto.Adapters.Postgres
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, 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
Ecto is commonly used to interact with databases, such as Postgres and MySQL via Ecto.Adapters.SQL (source code). Ecto is also commonly used to map data from any source into Elixir structs, regardless if they are backed by a database or not.
See the getting started guide and the online documentation for more information. Other resources available are:
-
Programming Ecto, by Darin Wilson and Eric Meadows-Jönsson, which guides you from fundamentals up to advanced concepts
-
The Little Ecto Cookbook, a free ebook by Plataformatec, which is a curation of the existing Ecto guides with some extra contents
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 | Dependencies | Ecto 3.0 compatible? |
---|---|---|---|
PostgreSQL | Ecto.Adapters.Postgres | ecto_sql postgrex | Yes |
MySQL | Ecto.Adapters.MyXQL | ecto_sql myxql | Yes |
MSSQL | MssqlEcto | ecto_sql mssql_ecto | No |
MSSQL | Tds.Ecto | ecto_sql tds_ecto | No |
SQLite | Sqlite.Ecto2 | ecto sqlite_ecto2 | No |
Mnesia | EctoMnesia.Adapter | ecto ecto_mnesia | No |
For example, if you want to use PostgreSQL, add to your mix.exs
file:
defp deps do
[
{:ecto_sql, "~> 3.0"},
{:postgrex, ">= 0.0.0"}
]
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 definition, you will need to specify the adapter:
respective to the chosen dependency. For PostgreSQL it is:
defmodule MyApp.Repo do
use Ecto.Repo,
otp_app: :my_app,
adapter: Ecto.Adapters.Postgres,
...
Branch | Support |
---|---|
v3.1 | Bug fixes |
v3.0 | Security patches only |
v2.2 | Security patches only |
v2.1 | Unsupported from 10/2018 |
v2.0 | Unsupported from 08/2017 |
v1.1 | Unsupported from 03/2018 |
v1.0 | Unsupported from 05/2017 |
With the version 3.0, Ecto has become API stable. This means no more new features, although we will continue providing bug fixes and updates. For everyone running Ecto in production, rest assured that Ecto will continue to be a well maintained project with the same production quality and polish that our users are familiar with.
Clone the repo and fetch its dependencies:
$ git clone https://github.com/elixir-ecto/ecto.git
$ cd ecto
$ mix deps.get
$ mix test
Note that mix test
does not run the tests in the integration_test
folder. To run integration tests, you can clone ecto_sql
in a sibling directory and then run its integration tests with the ECTO_PATH
environment variable pointing to your Ecto checkout:
$ cd ..
$ git clone https://github.com/elixir-ecto/ecto_sql.git
$ cd ecto_sql
$ ECTO_PATH=../ecto mix test.all
"Ecto" and the Ecto logo are Copyright (c) 2013 Plataformatec.
The Ecto logo was designed by Dane Wesolko.
The source code is under the Apache License 2.0.
Copyright (c) 2013 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.