Enum Consistency

#[repr(u16)]
pub enum Consistency {
    Any = 0,
    One = 1,
    Two = 2,
    Three = 3,
    Quorum = 4,
    All = 5,
    LocalQuorum = 6,
    EachQuorum = 7,
    LocalOne = 10,
    Serial = 8,
    LocalSerial = 9,
}

A setting that defines a successful write or read by the number of cluster replicas that acknowledge the write or respond to the read request, respectively. See ScyllaDB docs for more detailed description and guidelines.

Variants

Any = 0

Write-only. Closest replica, as determined by the Snitch, must respond. If all replica nodes are down, write succeeds after a hinted handoff. Provides low latency, guarantees writes never fail.

One = 1

The closest replica as determined by the Snitch must respond. Consistency requirements are not too strict.

Two = 2

The closest two replicas as determined by the Snitch must respond.

Three = 3

The closest three replicas as determined by the Snitch must respond.

Quorum = 4

A simple majority of all replicas across all datacenters must respond. This CL allows for some level of failure.

All = 5

All replicas in the cluster must respond. May cause performance issues.

LocalQuorum = 6

Same as QUORUM, but confined to the same datacenter as the coordinator.

EachQuorum = 7

Write-only. A simple majority in each datacenter must respond.

LocalOne = 10

Same as ONE, but confined to the local datacenter.

Serial = 8

Read-only. Returns results with the most recent data. Including uncommitted in-flight LWTs.

LocalSerial = 9

Read-only. Same as SERIAL, but confined to a local datacenter.

Implementations

impl Consistency

pub fn is_serial(&self) -> bool

Checks if the consistency is a serial consistency.

Trait Implementations

impl Clone for Consistency

fn clone(&self) -> Consistency

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for Consistency

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

Formats the value using the given formatter.

impl Default for Consistency

fn default() -> Consistency

Returns the “default value” for a type.

impl Display for Consistency

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

Formats the value using the given formatter.

impl Ord for Consistency

fn cmp(&self, other: &Consistency) -> 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 Consistency

fn eq(&self, other: &Consistency) -> 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 Consistency

fn partial_cmp(&self, other: &Consistency) -> 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 TryFrom<Consistency> for SerialConsistency

type Error = NonSerialConsistencyError

The type returned in the event of a conversion error.

fn try_from( c: Consistency, ) -> Result<SerialConsistency, <SerialConsistency as TryFrom<Consistency>>::Error>

Performs the conversion.

impl TryFrom<u16> for Consistency

type Error = TryFromPrimitiveError<u16>

The type returned in the event of a conversion error.

fn try_from( value: u16, ) -> Result<Consistency, <Consistency as TryFrom<u16>>::Error>

Performs the conversion.

impl Copy for Consistency

impl Eq for Consistency

impl StructuralPartialEq for Consistency