Programming Phoenix

Diving Deeper into Ecto Queries

So far, you know Ecto queries like a YouTube dog knows how to ride a bike. We’ve written our first query and we know that queries compose, but we still haven’t explored many concepts. It’s time to take off the training wheels and see more-advanced examples.

Open up IEx once more, and let’s retrieve a single user:

iex> import Ecto.Query
iex> alias Rumbl.Repo
iex> alias Rumbl.User

iex> username = "josevalim"
"josevalim"

iex> Repo.one(from u in User, where: u.username == ^username)
...
%Rumbl.User{username: "josevalim", ...}

We’re using the same concepts you learned before:

• Repo.one means return one row.

• from u in User means we’re reading from the User schema.

• where: u.username == ...