Struct Key

pub struct Key { /* private fields */ }

Represents a DynamoDB key condition expression.

An instance can be constructed using the Path::key method, or the the From<T: Into<Path>> implementation.

See also: Path::key

use dynamodb_expression::{key::Key, Path};

let key: Key = "foo".parse::<Path>()?.key();
let key: Key = "foo".parse::<Path>()?.into();

Implementations

impl Key

pub fn begins_with<T>(self, prefix: T) -> KeyCondition

where T: Into<StringOrRef>,

The DynamoDB begins_with function. True if the attribute specified by the Path begins with a particular substring.

begins_with can take a string or a reference to an extended attribute value. Here’s an example.

See also: Ref

use dynamodb_expression::{condition::BeginsWith, value::Ref, Path};

let key_condition = "foo".parse::<Path>()?.key().begins_with("T");
assert_eq!(r#"begins_with(foo, "T")"#, key_condition.to_string());

let key_condition = "foo".parse::<Path>()?.key().begins_with(Ref::new("prefix"));
assert_eq!(r#"begins_with(foo, :prefix)"#, key_condition.to_string());

pub fn between<L, U>(self, lower: L, upper: U) -> KeyCondition

where L: Into<Operand>, U: Into<Operand>,

The DynamoDB BETWEEN operator. True if self is greater than or equal to lower, and less than or equal to upper.

See also: Path::between

use dynamodb_expression::{Num, Path};

let key_condition = "age"
    .parse::<Path>()?
    .key()
    .between(Num::new(10), Num::new(90));
assert_eq!(r#"age BETWEEN 10 AND 90"#, key_condition.to_string());

pub fn equal<T>(self, right: T) -> KeyCondition

where T: Into<Operand>,

A simple comparison that the specified attribute is equal to the provided value.

pub fn greater_than<T>(self, right: T) -> KeyCondition

where T: Into<Operand>,

A simple comparison that the specified attribute is greater than the provided value.

pub fn greater_than_or_equal<T>(self, right: T) -> KeyCondition

where T: Into<Operand>,

A simple comparison that the specified attribute is greater than or equal to the provided value.

pub fn less_than<T>(self, right: T) -> KeyCondition

where T: Into<Operand>,

A simple comparison that the specified attribute is less than the provided value.

pub fn less_than_or_equal<T>(self, right: T) -> KeyCondition

where T: Into<Operand>,

A simple comparison that the specified attribute is less than or equal to the provided value.

Trait Implementations

impl Clone for Key

fn clone(&self) -> Key

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for Key

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

Formats the value using the given formatter.

impl<T> From<T> for Key

where T: Into<Path>,

fn from(path: T) -> Self

Convert something that implements Into<Path> into a Key.

impl Ord for Key

fn cmp(&self, other: &Key) -> Ordering

This method returns an Ordering between self and other.

fn max(self, other: Self) -> Self

where Self: Sized,

Compares and returns the maximum of two values.

fn min(self, other: Self) -> Self

where Self: Sized,

Compares and returns the minimum of two values.

fn clamp(self, min: Self, max: Self) -> Self

where Self: Sized,

Restrict a value to a certain interval.

impl PartialEq for Key

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

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl PartialOrd for Key

fn partial_cmp(&self, other: &Key) -> Option<Ordering>

This method returns an ordering between self and other values if one exists.

fn lt(&self, other: &Rhs) -> bool

Tests less than (for self and other) and is used by the < operator.

fn le(&self, other: &Rhs) -> bool

Tests less than or equal to (for self and other) and is used by the <= operator.

fn gt(&self, other: &Rhs) -> bool

Tests greater than (for self and other) and is used by the > operator.

fn ge(&self, other: &Rhs) -> bool

Tests greater than or equal to (for self and other) and is used by the >= operator.

impl Eq for Key

impl StructuralPartialEq for Key