Implement date/time -> string formatting functions

[alamb]

Is your feature request related to a problem or challenge?

Asked about in Discord

DataFusion doesn't have any time formatting functions, right? i.e. something like date_time.format("%d/%m/%Y")

The idea is to be able to format timestamps / dates back to different formats of strings

Describe the solution you'd like

Implement some sort of date/time/timestamp -> string formatting function that takes a user defined formatting string (probably chrono format) and returns a string

For example the postgres to_char function does this:
https://www.postgresql.org/docs/current/functions-formatting.html

Spark may have a better API (I haven't researched it)

arrow-rs already has the actual formatting code in ArrayFormatter:
https://docs.rs/arrow/latest/arrow/util/display/struct.ArrayFormatter.html

And specify by
https://docs.rs/arrow/latest/arrow/util/display/struct.FormatOptions.html

So this project is likely just to define a function, wire it in, and write some tests

Describe alternatives you've considered

No response

Additional context

No response

[Omega359]

I'll work on this next if no one minds

[Omega359]

Spark api has a different name (date_format) but otherwise is very similar. I plan on having both names and have the spark one be an alias.

The pg to_char function also handles numbers which I think should be something we can either handle in this ticket or as a future improvement.

[alamb]

Thank you @Omega359