Struct PlanCache 

pub struct PlanCache { /* private fields */ }

LRU cache for query plans

Implementations

impl PlanCache

pub fn new(capacity: usize) -> Self

Create a new plan cache with the given capacity

pub fn with_ttl(self, ttl: Duration) -> Self

Set the TTL for cache entries

pub fn peek(&self, key: &str) -> Option<&CachedPlan>

Read-only cache probe — no LRU promotion, no mutation.

Use this with a read() lock in the hot query path so concurrent readers don’t serialize on a write lock. Falls back to None when the entry is expired or has a pending replan; the caller must then re-acquire a write() lock and call get() to handle eviction and miss insertion.

pub fn get(&mut self, key: &str) -> Option<&CachedPlan>

Get a cached plan by key

pub fn insert(&mut self, key: String, plan: CachedPlan)

Insert a plan into the cache

pub fn remove(&mut self, key: &str) -> Option<CachedPlan>

Remove an entry from the cache

pub fn invalidate<F>(&mut self, predicate: F)

where F: Fn(&str) -> bool,

Invalidate entries matching a predicate

pub fn clear(&mut self)

Clear all entries

pub fn stats(&self) -> CacheStats

Get cache statistics

pub fn prune_expired(&mut self)

Prune expired entries

pub fn record_observation(&mut self, key: &str, rows_scanned: u64)

Trait Implementations

impl Default for PlanCache

fn default() -> Self

Returns the “default value” for a type.