Enum WindowFunctionSpec 

#[non_exhaustive]
pub enum WindowFunctionSpec {
    RowNumber,
    Rank,
    DenseRank,
    Ntile {
        n: u32,
    },
    PercentRank,
    CumeDist,
    Lag {
        field: String,
        offset: i32,
        default: Option<Value>,
    },
    Lead {
        field: String,
        offset: i32,
        default: Option<Value>,
    },
    FirstValue {
        field: String,
    },
    LastValue {
        field: String,
    },
    NthValue {
        field: String,
        n: u32,
    },
    RunningSum {
        measure: String,
    },
    RunningAvg {
        measure: String,
    },
    RunningCount,
    RunningCountField {
        field: String,
    },
    RunningMin {
        measure: String,
    },
    RunningMax {
        measure: String,
    },
    RunningStddev {
        measure: String,
    },
    RunningVariance {
        measure: String,
    },
}

Window function specification using semantic field names.

Unlike WindowFunctionType which uses raw SQL expressions, this uses measure/dimension names that get validated against metadata.

Variants (Non-exhaustive)

Non-exhaustive enums could have additional variants added in future. Therefore, when matching against variants of non-exhaustive enums, an extra wildcard arm must be added to account for any future variants.

RowNumber

ROW_NUMBER() - Sequential number within partition

Rank

RANK() - Rank with gaps for ties

DenseRank

DENSE_RANK() - Rank without gaps

Ntile

NTILE(n) - Divide rows into n groups

Fields

n: u32

Number of groups

PercentRank

PERCENT_RANK() - Relative rank (0 to 1)

CumeDist

CUME_DIST() - Cumulative distribution

Lag

LAG(field, offset, default) - Value from previous row

Fields

field: String

Measure or dimension name

offset: i32

Row offset (default: 1)

default: Option<Value>

Default value when no previous row

Lead

LEAD(field, offset, default) - Value from next row

Fields

field: String

Measure or dimension name

offset: i32

Row offset (default: 1)

default: Option<Value>

Default value when no next row

FirstValue

FIRST_VALUE(field) - First value in window frame

Fields

field: String

Measure or dimension name

LastValue

LAST_VALUE(field) - Last value in window frame

Fields

field: String

Measure or dimension name

NthValue

NTH_VALUE(field, n) - Nth value in window frame

Fields

field: String

Measure or dimension name

n: u32

Position (1-indexed)

RunningSum

SUM(measure) OVER (…) - Running total

Fields

measure: String

Measure name

RunningAvg

AVG(measure) OVER (…) - Moving average

Fields

measure: String

Measure name

RunningCount

COUNT(*) OVER (…) - Running count

RunningCountField

COUNT(field) OVER (…) - Running count of non-null values

Fields

field: String

Measure or dimension name

RunningMin

MIN(measure) OVER (…) - Running minimum

Fields

measure: String

Measure name

RunningMax

MAX(measure) OVER (…) - Running maximum

Fields

measure: String

Measure name

RunningStddev

STDDEV(measure) OVER (…) - Running standard deviation

Fields

measure: String

Measure name

RunningVariance

VARIANCE(measure) OVER (…) - Running variance

Fields

measure: String

Measure name

Trait Implementations

impl Clone for WindowFunctionSpec

fn clone(&self) -> WindowFunctionSpec

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for WindowFunctionSpec

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

Formats the value using the given formatter.

impl<'de> Deserialize<'de> for WindowFunctionSpec

fn deserialize<__D>(__deserializer: __D) -> Result<Self, __D::Error>

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl PartialEq for WindowFunctionSpec

fn eq(&self, other: &WindowFunctionSpec) -> 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 Serialize for WindowFunctionSpec

fn serialize<__S>(&self, __serializer: __S) -> Result<__S::Ok, __S::Error>

where __S: Serializer,

Serialize this value into the given Serde serializer.

impl Eq for WindowFunctionSpec

impl StructuralPartialEq for WindowFunctionSpec