Maximilian Roos

WDYT about having something like `this` also operate on tables, like `from this.group` to refer to a table named `group`? In the same way that `derive x = this.group` refers...

Yes, currently `let` needs to resolve to a table / relation. Relaxing this would be good! It's not trivial in the compiler; and it would be less frequently used than...

I had a look at implementing this. It's not obvious how to do it. When we lower the expressions, we need to create a table instance, since that's the only...

Excellent examples @aljazerzen ! --- Some prior art of _generating_ arrays (which can easily be unnested into columns): [generate array](https://cloud.google.com/bigquery/docs/reference/standard-sql/array_functions#generate_array) & [generate date array](https://cloud.google.com/bigquery/docs/reference/standard-sql/array_functions#generate_date_array). --- While the examples above are...

I don't think this is related to #3111, but it does look like a bug. Here's the example minimized: ```elm from invoices group {billing_country, customer_id} ( aggregate (c=count invoice_id) )...

I agree re compiling to `COUNT(DISTINCT t.*)`. Do we know whether other DBs support this?

Edit: this specific example is done! Thanks to @nkicg6 in #3985. I'm leaving the broader issue open since there's lots more out there... --- As an example of the issue,...

> I'll keep chipping away at this, like you said it is a good way to get the hang of the compiler! Great! And if there are questions like "what...

I just merged #3987, which now includes the [`prqlc` binary tests](https://github.com/PRQL/prql/blob/f4f80e115fa139ca309a0a61c8ebf2e4047cea3f/prqlc/prqlc/tests/test.rs) as an input to coverage. So now we have a more accurate picture of what's covered...

`prql-ast` looks fairly well covered, but definitely still holes. For sure feel free to remove `test = false` if we can add tests there (it's not a policy, we just...