sqlp: add ability to handle different decimal operators

[jqnatividad]

          @jqnatividad I'm adding a problem, that I'm able to manage using duckdb.

In Italy, the floating separator is , and not the . If I use qsv to import OpenCoesione data, all the numeric fields are mapped as string (because we have the ,).

In duckdb I solve using decimal_separator=',' parameter.
If there is something similar in polar, it would be very useful to have it also in qsv.

Originally posted by @aborruso in #1047 (comment)

[jqnatividad]

Unfortunately @aborruso , at the moment, this is not available in the current version of Polars.

There's an open issue for it though -
pola-rs/polars#6698

In the meantime, you can use apply operations thousands in your pipeline to convert the comma decimal separator to the dot decimal separator, before passing it to sqlp, and then convert it back to the comma decimal separator with the apply operations thousands command.

[aborruso]

Thank you very much

[github-actions]

Stale issue message

[github-actions]

Stale issue message

[jqnatividad]

This is still open on polars repo...

[github-actions]

Stale issue message

[jqnatividad]

This remains an open issue in Polars...

[jqnatividad]

Glad to report that configurable decimal operators are now supported in Polars main!
pola-rs/polars#15774

Hopefully, it finds its way into polars-sql...

[jqnatividad]

Just opened a feature request issue asking for Polars SQL support

pola-rs/polars#15786

[jqnatividad]

With the --decimal-comma option, you can now read input data with floats using comma as a decimal separator instead of period.

Bear in mind that you'll need to specify an alternate delimiter as well (not the default comma delimiter)

[aborruso]

Thank you very much