Trait mz_adapter::coord::timestamp_selection::TimestampProvider

pub trait TimestampProvider {
    // Required methods
    fn compute_read_frontier(
        &self,
        instance: ComputeInstanceId,
        id: GlobalId,
    ) -> Antichain<Timestamp>;
    fn compute_write_frontier(
        &self,
        instance: ComputeInstanceId,
        id: GlobalId,
    ) -> Antichain<Timestamp>;
    fn storage_frontiers(
        &self,
        ids: Vec<GlobalId>,
    ) -> Vec<(GlobalId, Antichain<Timestamp>, Antichain<Timestamp>)>;
    fn catalog_state(&self) -> &CatalogState;
    fn acquire_read_holds(
        &self,
        id_bundle: &CollectionIdBundle,
    ) -> ReadHolds<Timestamp>;

    // Provided methods
    fn get_timeline(timeline_context: &TimelineContext) -> Option<Timeline> { ... }
    fn needs_linearized_read_ts(
        isolation_level: &IsolationLevel,
        when: &QueryWhen,
    ) -> bool { ... }
    fn determine_timestamp_for(
        &self,
        session: &Session,
        id_bundle: &CollectionIdBundle,
        when: &QueryWhen,
        compute_instance: ComputeInstanceId,
        timeline_context: &TimelineContext,
        oracle_read_ts: Option<Timestamp>,
        real_time_recency_ts: Option<Timestamp>,
        isolation_level: &IsolationLevel,
    ) -> Result<(TimestampDetermination<Timestamp>, ReadHolds<Timestamp>), AdapterError> { ... }
    fn least_valid_read(
        &self,
        read_holds: &ReadHolds<Timestamp>,
    ) -> Antichain<Timestamp> { ... }
    fn least_valid_write(
        &self,
        id_bundle: &CollectionIdBundle,
    ) -> Antichain<Timestamp> { ... }
    fn greatest_available_read(
        &self,
        id_bundle: &CollectionIdBundle,
    ) -> Antichain<Timestamp> { ... }
}

Required Methods

fn compute_read_frontier( &self, instance: ComputeInstanceId, id: GlobalId, ) -> Antichain<Timestamp>

fn compute_write_frontier( &self, instance: ComputeInstanceId, id: GlobalId, ) -> Antichain<Timestamp>

fn storage_frontiers( &self, ids: Vec<GlobalId>, ) -> Vec<(GlobalId, Antichain<Timestamp>, Antichain<Timestamp>)>

Returns the implied capability (since) and write frontier (upper) for the specified storage collections.

fn catalog_state(&self) -> &CatalogState

fn acquire_read_holds( &self, id_bundle: &CollectionIdBundle, ) -> ReadHolds<Timestamp>

Acquires ReadHolds, for the given id_bundle at the earliest possible times.

Provided Methods

fn get_timeline(timeline_context: &TimelineContext) -> Option<Timeline>

fn needs_linearized_read_ts( isolation_level: &IsolationLevel, when: &QueryWhen, ) -> bool

Returns true if-and-only-if the given configuration needs a linearized read timetamp from a timestamp oracle.

This assumes that the query happens in the context of a timeline. If there is no timeline, we cannot and don’t have to get a linearized read timestamp.

fn determine_timestamp_for( &self, session: &Session, id_bundle: &CollectionIdBundle, when: &QueryWhen, compute_instance: ComputeInstanceId, timeline_context: &TimelineContext, oracle_read_ts: Option<Timestamp>, real_time_recency_ts: Option<Timestamp>, isolation_level: &IsolationLevel, ) -> Result<(TimestampDetermination<Timestamp>, ReadHolds<Timestamp>), AdapterError>

Determines the timestamp for a query.

Timestamp determination may fail due to the restricted validity of traces. Each has a since and upper frontier, and are only valid after since and sure to be available not after upper.

The timeline that id_bundle belongs to is also returned, if one exists.

fn least_valid_read( &self, read_holds: &ReadHolds<Timestamp>, ) -> Antichain<Timestamp>

The smallest common valid read frontier among times in the given ReadHolds.

fn least_valid_write( &self, id_bundle: &CollectionIdBundle, ) -> Antichain<Timestamp>

The smallest common valid write frontier among the specified collections.

Times that are not greater or equal to this frontier are complete for all collections identified as arguments.

fn greatest_available_read( &self, id_bundle: &CollectionIdBundle, ) -> Antichain<Timestamp>

Returns least_valid_write - 1, i.e., each time in least_valid_write stepped back in a saturating way.

Object Safety

This trait is not object safe.

Implementors

impl TimestampProvider for Coordinator