Struct TakeOperator 

pub struct TakeOperator { /* private fields */ }

Implementations

impl TakeOperator

pub fn new(parent: Arc<Operators>, node: FlowNodeId, limit: usize) -> Self

Trait Implementations

impl Operator for TakeOperator

fn id(&self) -> FlowNodeId

fn apply(&self, txn: &mut FlowTransaction, change: Change) -> Result<Change>

fn pull(&self, txn: &mut FlowTransaction, rows: &[RowNumber]) -> Result<Columns>

fn tick( &self, _txn: &mut FlowTransaction, _timestamp: DateTime, ) -> Result<Option<Change>>

Periodic tick for time-based maintenance (e.g., window eviction). Returns Some(Change) with diffs if maintenance produced changes.

impl RawStatefulOperator for TakeOperator

fn state_get( &self, txn: &mut FlowTransaction, key: &EncodedKey, ) -> Result<Option<EncodedRow>>

Get raw bytes for a key

fn state_set( &self, txn: &mut FlowTransaction, key: &EncodedKey, value: EncodedRow, ) -> Result<()>

Set raw bytes for a key

fn state_remove( &self, txn: &mut FlowTransaction, key: &EncodedKey, ) -> Result<()>

Remove a key

fn state_scan(&self, txn: &mut FlowTransaction) -> Result<StateIterator>

Scan all keys for this operator

fn state_range( &self, txn: &mut FlowTransaction, range: EncodedKeyRange, ) -> Result<StateIterator>

Range query between keys

fn state_clear(&self, txn: &mut FlowTransaction) -> Result<()>

Clear all state for this operator

impl SingleStateful for TakeOperator

fn layout(&self) -> RowSchema

Get or create the layout for state rows

fn key(&self) -> EncodedKey

Key for the single state - default is empty

fn create_state(&self) -> EncodedRow

Create a new state encoded with default values

fn load_state(&self, txn: &mut FlowTransaction) -> Result<EncodedRow>

Load the operator’s single state encoded

fn save_state(&self, txn: &mut FlowTransaction, row: EncodedRow) -> Result<()>

Save the operator’s single state encoded

fn update_state<F>(&self, txn: &mut FlowTransaction, f: F) -> Result<EncodedRow>

where F: FnOnce(&RowSchema, &mut EncodedRow) -> Result<()>,

Update state with a function

fn clear_state(&self, txn: &mut FlowTransaction) -> Result<()>

Clear state