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>

impl RawStatefulOperator for TakeOperator

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

Get raw bytes for a key

fn state_set( &self, txn: &mut FlowTransaction, key: &EncodedKey, value: EncodedValues, ) -> 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) -> Schema

Get or create the layout for state rows

fn key(&self) -> EncodedKey

Key for the single state - default is empty

fn create_state(&self) -> EncodedValues

Create a new state encoded with default values

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

Load the operator’s single state encoded

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

Save the operator’s single state encoded

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

where F: FnOnce(&Schema, &mut EncodedValues) -> Result<()>,

Update state with a function

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

Clear state