On: Show HN: PRQL 0.2 – a better SQL

[davidw]

A good example might be a groupwise maximum. Those always tend to be a bit of a PITA in SQL if you're not writing them regularly. Be interesting to see what it transpiles to, as well.

[aerzen → davidw]

If you only want maximum of one column, the PRQL is quite simple:

    from my_table
    group column_a (
      aggregate (max column_b)
    )

If you want the row with the maximum value it gets interesting:

    from my_table
    group column_a (
      sort [-column_b]
      take 1
    )

You can read more about group here: https://prql-lang.org/book/transforms/group.html

[beaugunderson → aerzen]

Opened an issue as I couldn't get this to work against sqlite:

https://github.com/prql/prql/issues/695

[maximilianroos → beaugunderson]

Thanks a lot for testing and opening an issue! This is now fixed and released [1]. Let us know if you still face any problems.

(We need better tests against real DBs, which is very much on our roadmap)

[1]: https://github.com/prql/prql/pull/698

[beaugunderson → maximilianroos]

Thank you for the amazingly quick fix!