Enum WindowFn 

pub enum WindowFn {
    RowNumber,
    Rank {
        order_column: Option<String>,
    },
    DenseRank {
        order_column: Option<String>,
    },
    Lead {
        offset: usize,
        default: f64,
    },
    Lag {
        offset: usize,
        default: f64,
    },
    Delta,
    Rate,
    IRate,
    MovingAverage {
        window_size: usize,
    },
    CumulativeSum,
    Increase,
    RangeMovingAverage {
        range_ns: i64,
    },
    RangeSum {
        range_ns: i64,
    },
    RangeCount {
        range_ns: i64,
    },
}

Window function type.

Variants

RowNumber

Sequential 1-based row number within partition.

Rank

Rank with gaps for ties on the order column.

When order_column is Some, rank is determined by that column (SQL standard RANK() OVER (ORDER BY ...)). When None, defaults to the value column for backward compatibility.

Fields

order_column: Option<String>

Column to determine rank ordering. None uses the value column.

DenseRank

Rank without gaps for ties on the order column.

Same order_column semantics as Rank.

Fields

order_column: Option<String>

Column to determine rank ordering. None uses the value column.

Lead

Value offset rows ahead; default if out of range.

Fields

offset: usize

Number of rows to look ahead.

default: f64

Default value when the look-ahead extends past the partition end.

Lag

Value offset rows behind; default if out of range.

Fields

offset: usize

Number of rows to look behind.

default: f64

Default value when the look-behind extends before the partition start.

Delta

Difference: value[i] - value[i-1] (null for first row).

Rate

Per-second rate: (value[i] - value[i-1]) / (timestamp[i] - timestamp[i-1]).

Timestamp unit assumption

Timestamps are assumed to be nanoseconds since the Unix epoch (the standard unit throughout Chronix). The delta is divided by 1_000_000_000.0 to convert to seconds before computing the rate. If timestamps use a different unit (e.g. microseconds or millis), the rate values will be incorrect by the corresponding scale factor.

IRate

Instantaneous per-second rate between the last two samples in the partition. Every row in the partition gets the same value.

Uses the same nanosecond timestamp assumption as Rate.

MovingAverage

Simple moving average over a sliding window of window_size rows.

Fields

window_size: usize

Number of rows in the sliding window.

CumulativeSum

Running cumulative sum.

Increase

Monotonic counter increase (resets to 0 on counter wrap-around).

RangeMovingAverage

RANGE-frame moving average over a timestamp window.

For each row, computes the mean of all values whose timestamps fall within [current_ts - range_ns, current_ts]. Uses an efficient two-pointer O(n) scan (data is sorted by timestamp).

Fields

range_ns: i64

Window size in nanoseconds.

RangeSum

RANGE-frame sum over a timestamp window.

Fields

range_ns: i64

Window size in nanoseconds.

RangeCount

RANGE-frame count over a timestamp window.

Fields

range_ns: i64

Window size in nanoseconds.

Trait Implementations

impl Clone for WindowFn

fn clone(&self) -> WindowFn

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for WindowFn

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

Formats the value using the given formatter.

impl PartialEq for WindowFn

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

Equality operator ==.

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

Inequality operator !=.

impl StructuralPartialEq for WindowFn