<datetime> / <duration> feature is questionable, possibly should be removed.

[finnbear]

SurrealDB implements division for datetime divided by duration: select time::now() / 1w, which truncates the datetime to the duration.

The implementation of the feature is questionable because:

• v and w are reversed here (should be v / w):

  surrealdb/lib/src/sql/value/value.rs

  Line 1234 in 5fe1fd0

  (Value::Datetime(v), Value::Duration(w)) => Value::Datetime(w / v),

The feature itself is questionable because:

• Division truncates instead of dividing:

  surrealdb/lib/src/sql/duration.rs

  Lines 207 to 218 in 5fe1fd0

  	impl ops::Div<Datetime> for Duration {
  	type Output = Datetime;
  	fn div(self, other: Datetime) -> Datetime {
  	match chrono::Duration::from_std(self.0) {
  	Ok(d) => match other.duration_trunc(d) {
  	Ok(v) => Datetime::from(v),
  	Err(_) => Datetime::default(),
  	},
  	Err(_) => Datetime::default(),
  	}
  	}
  	}

• time::floor seems like a canonical, much more clear way to truncate datetimes

My idea is to either:

• Remove this type of division
• Reverse v and w in the implementation

Thoughts?

[tobiemh]

@finnbear I've added an issue for this: #1213. Given that:

1. It doesn't actually make sense to divide by durations
2. I had to read through the code and remind myself about the functionality
3. It's not actually documented anywhere, so no harm in removing this behaviour
4. We have the time::floor function which enables you to do the same thing

Let's get rid of it.