pub enum NullHandling {
    First,
    Last,
}
Expand description

Describes how NULL values should be ordered when sorting. We refer to None values returned from PartialOrdBy::partial_cmp_by as NULL. Warning: Rust’s Option::None is not strictly equivalent to SQL’s NULL but we borrow from SQL terminology to handle them.

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First

Places all NULL values first.

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Last

Places all NULL values last. The default.

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impl Clone for NullHandling

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fn clone(&self) -> NullHandling

Returns a copy of the value. Read more
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fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source. Read more
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impl Debug for NullHandling

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fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter. Read more
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impl Default for NullHandling

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fn default() -> NullHandling

Returns the “default value” for a type. Read more
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impl PartialEq<NullHandling> for NullHandling

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fn eq(&self, other: &NullHandling) -> bool

This method tests for self and other values to be equal, and is used by ==.
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fn ne(&self, other: &Rhs) -> bool

This method tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.
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impl Copy for NullHandling

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impl StructuralPartialEq for NullHandling

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impl<T> Any for Twhere T: 'static + ?Sized,

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fn type_id(&self) -> TypeId

Gets the TypeId of self. Read more
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impl<T> Borrow<T> for Twhere T: ?Sized,

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fn borrow(&self) -> &T

Immutably borrows from an owned value. Read more
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impl<T> BorrowMut<T> for Twhere T: ?Sized,

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fn borrow_mut(&mut self) -> &mut T

Mutably borrows from an owned value. Read more
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impl<T> From<T> for T

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fn from(t: T) -> T

Returns the argument unchanged.

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impl<T, U> Into<U> for Twhere U: From<T>,

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fn into(self) -> U

Calls U::from(self).

That is, this conversion is whatever the implementation of From<T> for U chooses to do.

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impl<T> Same<T> for T

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type Output = T

Should always be Self
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impl<T> To for Twhere T: ?Sized,

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fn to<T>(self) -> Twhere Self: Into<T>,

Converts to T by calling Into<T>::into.
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fn try_to<T>(self) -> Result<T, Self::Error>where Self: TryInto<T>,

Tries to convert to T by calling TryInto<T>::try_into.
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impl<T> ToOwned for Twhere T: Clone,

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type Owned = T

The resulting type after obtaining ownership.
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fn to_owned(&self) -> T

Creates owned data from borrowed data, usually by cloning. Read more
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fn clone_into(&self, target: &mut T)

Uses borrowed data to replace owned data, usually by cloning. Read more
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impl<T, U> TryFrom<U> for Twhere U: Into<T>,

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type Error = Infallible

The type returned in the event of a conversion error.
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fn try_from(value: U) -> Result<T, <T as TryFrom<U>>::Error>

Performs the conversion.
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impl<T, U> TryInto<U> for Twhere U: TryFrom<T>,

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type Error = <U as TryFrom<T>>::Error

The type returned in the event of a conversion error.
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fn try_into(self) -> Result<U, <U as TryFrom<T>>::Error>

Performs the conversion.
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impl<T> Dep for Twhere T: 'static + PartialEq<T> + Clone,