Struct CorrectionFeatures 

pub struct CorrectionFeatures {
    pub baseline_estimate: u64,
    pub left_input_rows: Option<u64>,
    pub right_input_rows: Option<u64>,
    pub left_distinct: Option<u64>,
    pub right_distinct: Option<u64>,
    pub predicate_count: u32,
    pub join_depth: u32,
}

Feature vector handed to the corrector at estimate time.

Intentionally minimal at v0.0.1: row count + distinct count + null count + a small set of operator-level features. Will grow as the feedback-collection surface widens.

Examples

use samkhya_core::residual::CorrectionFeatures;

let features = CorrectionFeatures {
    baseline_estimate: 1000,
    left_input_rows: Some(500),
    right_input_rows: Some(2000),
    predicate_count: 2,
    join_depth: 1,
    ..Default::default()
};
assert_eq!(features.to_vec().len(), CorrectionFeatures::FEATURE_LEN);

Fields

baseline_estimate: u64

left_input_rows: Option<u64>

right_input_rows: Option<u64>

left_distinct: Option<u64>

right_distinct: Option<u64>

predicate_count: u32

join_depth: u32

Implementations

impl CorrectionFeatures

pub const FEATURE_LEN: usize = 7

Number of entries to_vec produces.

pub fn to_vec(&self) -> Vec<f64>

Flatten the feature struct into a fixed-length numeric vector for a regression model. Option<u64> slots are zero-filled when absent — callers should treat zero as “unknown” rather than “literally zero rows”, which is the convention the corrector is trained against.

Layout (stable; new features must be appended, never reordered):

0. baseline_estimate
1. left_input_rows (0 if None)
2. right_input_rows (0 if None)
3. left_distinct (0 if None)
4. right_distinct (0 if None)
5. predicate_count
6. join_depth

Examples

use samkhya_core::residual::CorrectionFeatures;

let f = CorrectionFeatures {
    baseline_estimate: 100,
    left_input_rows: Some(10),
    predicate_count: 3,
    ..Default::default()
};
let v = f.to_vec();
assert_eq!(v[0], 100.0);
assert_eq!(v[1], 10.0);
assert_eq!(v[2], 0.0); // None → 0
assert_eq!(v[5], 3.0);

Trait Implementations

impl Clone for CorrectionFeatures

fn clone(&self) -> CorrectionFeatures

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for CorrectionFeatures

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

Formats the value using the given formatter.

impl Default for CorrectionFeatures

fn default() -> CorrectionFeatures

Returns the “default value” for a type.