Add mix ecto.query task by cdvx · Pull Request #733 · elixir-ecto/ecto_sql

cdvx · 2026-06-12T11:59:39Z

Implements a read-only query Mix task run through the selected or default repo. Accepts --sql to render generated SQL and params for the passed query without running it, otherwise returns schema level output. Raises is adapter does not support read only transactions.

Closes elixir-ecto/ecto#4719 Implements a read-only query Mix task run through the selected or default repo. Accepts --sql to render generated SQL and params for the passed query without running it, otherwise returns schema level output. Raises is adapter does not support read only transactions.

josevalim

Sorry for the delay, I dropped what is likely the final batch of comments and we should be good!

Co-authored-by: José Valim <jose.valim@gmail.com>

- clean up tests - use inspect_fun opt instead of overriding global state for inspect - copy implementation of inspect/4 Inspect.Map protocol instead of calling private API directly - parse only aliases from .iex.exs

cdvx · 2026-06-23T11:57:08Z

Sorry for the delay, I dropped what is likely the final batch of comments and we should be good!

No worries at all, thanks for the thorough review! I’ve addressed the comments: .iex.exs now only contributes aliases, inspection uses inspect_fun, and the test setup is cleaned up.

josevalim · 2026-06-26T07:32:28Z

+
+  defp do_read_only_transaction(Ecto.Adapters.MyXQL, repo, fun) do
+    repo.checkout(fn ->
+      repo.query!("START TRANSACTION READ ONLY", [], log: false)


Ideally we would move this to the adapter behaviour itself, so SQLite3 and other databases can implement, but it can be done in another pull request. Something like repo.transaction(read_only: true).

josevalim · 2026-06-26T07:36:38Z

💚 💙 💜 💛 ❤️