View Source Adbc (adbc v0.6.5)

Bindings for Arrow Database Connectivity (ADBC).

Adbc provides a standard database interface using the Apache Arrow format.

Installation

First, add :adbc as a dependency in your mix.exs:

{:adbc, "~> 0.1"}

Now, in your config/config.exs, configure the drivers you are going to use:

config :adbc, :drivers, [:sqlite]

If you are using a notebook or scripting, you can also use Adbc.download_driver!/1 to dynamically download one.

Then start the database and the relevant connection processes in your supervision tree:

children = [
  {Adbc.Database,
   driver: :sqlite,
   process_options: [name: MyApp.DB]},
  {Adbc.Connection,
   database: MyApp.DB,
   process_options: [name: MyApp.Conn]}
]

Supervisor.start_link(children, strategy: :one_for_one)

In a notebook, the above would look like this:

db = Kino.start_child!({Adbc.Database, driver: :sqlite})
conn = Kino.start_child!({Adbc.Connection, database: db})

And now you can make queries with:

# For named connections
{:ok, _} = Adbc.Connection.query(MyApp.Conn, "SELECT 123")

# When using the conn PID directly
{:ok, _} = Adbc.Connection.query(conn, "SELECT 123")

Supported drivers

Below we list all drivers supported out of the box. You may also give the full path to a driver in the :driver option to load other existing drivers.

DuckDB

The DuckDB driver provides access to in-memory DuckDB databases.

Examples

{Adbc.Database, driver: :duckdb}

PostgreSQL

The PostgreSQL driver provides access to any database that supports the PostgreSQL wire format. It is implemented as a wrapper around libpq.

Examples

{Adbc.Database, driver: :postgresql, uri: "postgresql://postgres@localhost"}

You must pass the :uri option using Postgres' connection URI:

Sqlite

The SQLite driver provides access to SQLite databases.

Examples

{Adbc.Database, driver: :sqlite, uri: ":memory:"}
{Adbc.Database, driver: :sqlite, uri: "./db/my.db"}
{Adbc.Database, driver: :sqlite, uri: "file:/path/to/file/in/disk.db"}

The :uri option should be, ":memory:", a filename or URI filename. If omitted, it will default to an in-memory database, but one that is shared across all connections.

Snowflake

The Snowflake driver provides access to Snowflake Database Warehouses.

Examples

{Adbc.Database, driver: :snowflake, uri: "..."}

The Snowflake URI should be of one of the following formats:

user[:password]@account/database/schema[?param1=value1&paramN=valueN]
user[:password]@account/database[?param1=value1&paramN=valueN]
user[:password]@host:port/database/schema?account=user_account[&param1=value1&paramN=valueN]
host:port/database/schema?account=user_account[&param1=value1&paramN=valueN]

The first two are the most recommended formats. The schema, database and parameters are optional. See Account identifiers for more information.

Summary

Functions

Downloads a driver and raises in case of errors.

Functions

Link to this function

download_driver(driver, opts \\ [])

View Source
@spec download_driver(
  atom(),
  keyword()
) :: :ok | {:error, binary()}

Downloads a driver.

See Adbc module doc for all supports drivers. It returns :ok or {:error, binary}.

Link to this function

download_driver!(driver, opts \\ [])

View Source
@spec download_driver!(
  atom(),
  keyword()
) :: :ok

Downloads a driver and raises in case of errors.

See Adbc module doc for all supports drivers. It returns :ok.