[Enh]: Support for `how="cross" in DataFrame.join() - Githubissues

narwhals-dev / narwhals

Lightweight and extensible compatibility layer between Polars, pandas, cuDF, Modin, and more!

https://narwhals-dev.github.io/narwhals/

MIT License

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[Enh]: Support for `how="cross" in DataFrame.join() #301

Open DeaMariaLeon opened 2 weeks ago

DeaMariaLeon commented 2 weeks ago

We would like to learn about your use case. For example, if this feature is needed to adopt Narwhals in an open source project, could you please enter the link to it below?

No response

Please describe the purpose of the new feature or describe the problem to solve.

Needed for TPC-H query Q11. Issue https://github.com/narwhals-dev/narwhals/issues/282

Suggest a solution if possible.

No response

If you have tried alternatives, please describe them below.

No response

Would you want to open a pull request?

None

Additional information that may help us understand your needs.

No response

FBruzzesi commented 22 hours ago

I took a quick look. Polars docs say:

Returns the Cartesian product of rows from both tables

and also experimentally it seems that join keys are just disregarded. Is this correct?