Struct FeedbackStore 

pub struct FeedbackStore { /* private fields */ }

SQLite-backed feedback store.

Implementations

impl FeedbackStore

pub fn open(path: impl AsRef<Path>) -> Result<Self>

Open or create a store at path.

pub fn open_in_memory() -> Result<Self>

Open an in-memory store (test / ephemeral).

Examples

use samkhya_core::feedback::FeedbackStore;

let store = FeedbackStore::open_in_memory().unwrap();
assert_eq!(store.count().unwrap(), 0);

pub fn record_plan(&self, obs: &PlanObservation) -> Result<i64>

Record an observation with the plan-shape features the corrector will see at inference time.

Examples

use samkhya_core::feedback::{FeedbackStore, PlanObservation};
use samkhya_core::residual::CorrectionFeatures;

let store = FeedbackStore::open_in_memory().unwrap();
let obs = PlanObservation {
    template_hash: "job-slow".into(),
    plan_fingerprint: "hash-join#7".into(),
    features: CorrectionFeatures {
        baseline_estimate: 1_000,
        left_input_rows: Some(500),
        right_input_rows: Some(2_000),
        predicate_count: 2,
        join_depth: 3,
        ..Default::default()
    },
    actual_rows: 9_500,
    latency_ms: Some(12.5),
};
store.record_plan(&obs).unwrap();

let history = store.plan_history("job-slow").unwrap();
assert_eq!(history.len(), 1);
assert_eq!(history[0].features.join_depth, 3);

pub fn plan_history(&self, template_hash: &str) -> Result<Vec<PlanObservation>>

Return every observation for template_hash that carries plan features, oldest first.

Rows recorded through record have no features and are skipped: training on them would silently reintroduce the feature-space mismatch this type exists to prevent. The filter is predicate_count IS NOT NULL, which only record_plan sets.

pub fn record(&self, obs: &Observation) -> Result<i64>

Record an observation.

Examples

use samkhya_core::feedback::{FeedbackStore, Observation};

let store = FeedbackStore::open_in_memory().unwrap();
let obs = Observation {
    template_hash: "tpch-q1".into(),
    plan_fingerprint: "hash-join#42".into(),
    est_rows: 1000,
    actual_rows: 950,
    latency_ms: Some(12.5),
};
let id = store.record(&obs).unwrap();
assert!(id > 0);
assert_eq!(store.count().unwrap(), 1);

pub fn history(&self, template_hash: &str) -> Result<Vec<Observation>>

Return all observations for a given query template, oldest first.

pub fn count(&self) -> Result<u64>

Number of observations stored.