There are various features we could not support. The big ones are aggregates and certain expressions do not have a parallel (or one that we cared to build in the first release) in SQLite3. For example, concat_ws([list, of, things]) is not supported.

Aggregates are a pretty big feature and not being able to use them may or may not affect a given use case. You can always use calculations to extract similar data, but it likely won’t be usable in filters and sorts unless you write it as a fragment that does a subquery.

We will most likely be able to support all aggregate types except for list at some point, but we couldn’t use the implementation from ash_postgres because it uses lateral joins which are not available in SQLite3. Something new will need to be devised for AshSqlite.

Another issue w/ the current implementation is that the migration generator currently is essentially fully copied from AshPostgres but AshPostgres uses alter column and that is not supported by SQLite3, meaning that those migrations need to be adjusted by hand. We should fix the migration generator to have it do something like warn to the user and drop some comments in the migration file, or something like that. Still TBD.

While I’m using AshSqlite3 In https://ash-hq.org I will likely not need any advanced feature support at any point in the near future, so hopefully those that do use it can champion pushing it forward in the above regards.

If you encounter and issues, feel free to open tickets.

Exciting!

As far as the Ash ecosystem goes, were there any features of Ash Postgres which Ash Sqlite wasn’t able to support? Or are they full one to one replacements for each other?