Add Ecto support based on ClickhouseEcto

[Zarathustra2]

This is based on ClickhouseEcto.

Currently parameters are not being supported that needs to be added as well.

Also needs some tests...

Example:

defmodule Repo do
  use Ecto.Repo,
  adapter: Pillar.Ecto,
  loggers: [Ecto.LogEntry],
  hostname: "localhost",
  port: 8123,
  timeout: 60_000,
  pool_timeout: 60_000,
  ownership_timeout: 60_000,
  pool_size: 30,
  otp_app: :pillar
end


defmodule Trade do
  use Ecto.Schema

  @primary_key false
  schema "trades" do
    field :ticker, :string
    field :size, :integer
  end
end

import Ecto.Query

Repo.start_link()

q = from(t in Trade, select: %{ticker: t.ticker, vol: sum(t.size)}, group_by: t.ticker)
IO.inspect(Ecto.Adapters.SQL.to_sql(:all, Repo, q))

Repo.all(q) |> IO.inspect()

[sofakingworld]

For all Ecto requests will be used 1 connection?
Is pool needed here? Like in BulkInsertBuffer module

[sofakingworld]

At all it looks great for me, thanks for this improvement! ❤️

I would like to see some tests, for example as you provided in description.

Could you add

1. insert test
2. select test
3. join test

and add into 'readme.md' information, that there is experimental support of Ecto.Schema's

[Zarathustra2]

Yeah I also want to add some more macros for custom clickhouse functions

[Zarathustra2]

OMG @sofakingworld I got a first version working which also supports parameterised query - so no fear for SQL injection!

Parameterised like this: https://clickhouse.com/docs/en/interfaces/http#cli-queries-with-parameters

[Zarathustra2]

DateTime mapping back to ecto model does not work yet, looking into it

[Zarathustra2]

DateTime works now!

[ruslandoga]

👋 @Zarathustra2

I wonder if you considered using execute/5 callback to build the query instead of prepare/5 to avoid reconstructing params? That's how plausible/chto ended up working.

I would be interested to see where this approach leads though :) I tried it only briefly and gave up before making it work...

[Zarathustra2]

I did not, I didn't even know plausible/chto existed :O

[Zarathustra2]

Gonna try chto now, maybe I can drop/close my work here

[Zarathustra2]

@ruslandoga was chto always public or has it been made public recently? I am wondering how I missed it

[ruslandoga]

It's always been public in https://github.com/ruslandoga/chto and moved under Plausible org recently. However "always" in this case is just a few months.

[Zarathustra2]

damn, how did it never come up for me, arg.

Just tested it briefly and seems to work with out issues so far for me. (I am currently struggling with some fragments implementations in this PR).

I am not sure how my work would compare to your library, feels like your stuff is way more reliable & major than what I have done so far. (I have never worked with Ecto under the hood prior to this PR)

[ruslandoga]

way more reliable & major

The only known user so far is Plausible. So I'm not sure if it's indeed reliable for use cases outside of https://github.com/plausible/analytics ...

It would be great to have more users :)

[viniciussbs]

It would be great to have more users :)

I'm willing to use it. It would be nice if we have a place to chat, maybe on ClickHouse's Slack. I've seen @Zarathustra2 there - where I've found this MR - but I'm not sure if you are there too, @ruslandoga.