Struct ScalarWrapper 

pub struct ScalarWrapper {
    arg_type: DataType,
    scalar: BoxedExpression,
}

Wraps a scalar function that takes a list as input as an aggregate function.

Fields

arg_type: DataType

scalar: BoxedExpression

Implementations

impl ScalarWrapper

pub fn new(arg_type: DataType, scalar: BoxedExpression) -> Self

Creates a new scalar wrapper.

Trait Implementations

impl AggregateFunction for ScalarWrapper

fn create_state(&self) -> Result<AggregateState>

Creates an initial state of the aggregate function.

fn update<'life0, 'life1, 'life2, 'async_trait>( &'life0 self, state: &'life1 mut AggregateState, input: &'life2 StreamChunk, ) -> Pin<Box<dyn Future<Output = Result<()>> + Send + 'async_trait>>

where Self: 'async_trait, 'life0: 'async_trait, 'life1: 'async_trait, 'life2: 'async_trait,

Update the state with multiple rows.

All rows in the input chunk must be Insert.

fn update_range<'life0, 'life1, 'life2, 'async_trait>( &'life0 self, state: &'life1 mut AggregateState, input: &'life2 StreamChunk, range: Range<usize>, ) -> Pin<Box<dyn Future<Output = Result<()>> + Send + 'async_trait>>

where Self: 'async_trait, 'life0: 'async_trait, 'life1: 'async_trait, 'life2: 'async_trait,

Update the state with a range of rows.

fn get_result<'life0, 'life1, 'async_trait>( &'life0 self, state: &'life1 AggregateState, ) -> Pin<Box<dyn Future<Output = Result<Datum>> + Send + 'async_trait>>

where Self: 'async_trait, 'life0: 'async_trait, 'life1: 'async_trait,

Get aggregate result from the state.

fn encode_state(&self, _state: &AggregateState) -> Result<Datum>

Encode the state into a datum that can be stored in state table.

fn decode_state(&self, _datum: Datum) -> Result<AggregateState>

Decode the state from a datum in state table.

fn return_type(&self) -> DataType

Returns the return type of the aggregate function.

impl Debug for ScalarWrapper

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.