While it looks like a lot of work in FromIr.hs, you can rather review the type changes in `Hasura.Backends.MySQL.Types.Internal` and the changes to FromIr are only to reflect that. Essentially we're simplifying the FromIr code to not think about SQL-based joins: instead, FromIr produces fields necessary for the dataloader Plan/Execute to do their job properly.
I've done my best to ensure that all the hunks in the diff in this PR are minimal for slightly easier perusing.
I think future PRs will be more intentionally well structured, rather than created retroactively.
**Preceding PR:** #2549
**Next PR**: #2367
The tests have been run like this on my machine. I don't know more beyond that.
```
docker run -i -e "PYTEST_ADDOPTS=--color=yes" -e "TERM=xterm-256color" --net=host -v`pwd`:`pwd` -w`pwd`/server/tests-py chrisdone/hasura-pytest:b0f26f615 pytest --hge-urls="http://localhost:8080" --pg-urls="postgres://chinook:chinook@localhost:5432/chinook" --backend mysql -k MySQL
```
PR-URL: https://github.com/hasura/graphql-engine-mono/pull/2608
Co-authored-by: Abby Sassel <3883855+sassela@users.noreply.github.com>
GitOrigin-RevId: a6483335c3036963360dde7d7d7eaf10859351cb
