Add :ecto
to the list of dependencies in mix.exs
:
def deps do
[
{:ecto, "~> 3.10"}
]
end
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 PostgreSQL and MySQL via Ecto.Adapters.SQL (source code). Ecto is also commonly used to map data from any source into Elixir structs, whether 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 Dashbit, 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 |
---|---|---|
PostgreSQL | Ecto.Adapters.Postgres | ecto_sql + postgrex |
MySQL | Ecto.Adapters.MyXQL | ecto_sql + myxql |
MSSQL | Ecto.Adapters.Tds | ecto_sql + tds |
SQLite3 | Ecto.Adapters.SQLite3 | ecto_sqlite3 |
ClickHouse | Ecto.Adapters.ClickHouse | ecto_ch |
ETS | Etso | etso |
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 |
---|---|
v3.12 | Bug fixes |
v3.11 | Security patches only |
v3.10 | Security patches only |
v3.9 | Security patches only |
v3.8 | Security patches only |
v3.7 and earlier | Unsupported |
With version 3.0, Ecto API has become stable. Our main focus is on providing bug fixes and incremental changes.
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
$ mix deps.get
$ ECTO_PATH=../ecto mix test.all
It is also possible to run the integration tests under a containerized environment using earthly:
$ earthly -P +all
You can also use this to interactively debug any failing integration tests using:
$ earthly -P -i --build-arg ELIXIR_BASE=1.8.2-erlang-21.3.8.21-alpine-3.13.1 +integration-test
Then once you enter the containerized shell, you can inspect the underlying databases with the respective commands:
PGPASSWORD=postgres psql -h 127.0.0.1 -U postgres -d postgres ecto_test
MYSQL_PASSWORD=root mysql -h 127.0.0.1 -uroot -proot ecto_test
sqlcmd -U sa -P 'some!Password'
"Ecto" and the Ecto logo are Copyright (c) 2020 Dashbit.
The Ecto logo was designed by Dane Wesolko.
Copyright (c) 2013 Plataformatec
Copyright (c) 2020 Dashbit
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 https://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.