Struct datafusion::prelude::SimpleAggregateUDF

pub struct SimpleAggregateUDF { /* private fields */ }

Implements AggregateUDFImpl for functions that have a single signature and return type.

Implementations

impl SimpleAggregateUDF

pub fn new( name: impl Into<String>, input_type: Vec<DataType>, return_type: DataType, volatility: Volatility, accumulator: Arc<dyn Fn(&DataType) -> Result<Box<dyn Accumulator>, DataFusionError> + Send + Sync>, state_type: Vec<DataType> ) -> SimpleAggregateUDF

Create a new AggregateUDFImpl from a name, input types, return type, state type and implementation. Implementing AggregateUDFImpl allows more flexibility

pub fn new_with_signature( name: impl Into<String>, signature: Signature, return_type: DataType, accumulator: Arc<dyn Fn(&DataType) -> Result<Box<dyn Accumulator>, DataFusionError> + Send + Sync>, state_type: Vec<DataType> ) -> SimpleAggregateUDF

Trait Implementations

impl AggregateUDFImpl for SimpleAggregateUDF

fn as_any(&self) -> &(dyn Any + 'static)

Returns this object as an Any trait object

fn name(&self) -> &str

Returns this function’s name

fn signature(&self) -> &Signature

Returns the function’s Signature for information about what input types are accepted and the function’s Volatility.

fn return_type( &self, _arg_types: &[DataType] ) -> Result<DataType, DataFusionError>

What DataType will be returned by this function, given the types of the arguments

fn accumulator( &self, arg: &DataType ) -> Result<Box<dyn Accumulator>, DataFusionError>

Return a new Accumulator that aggregates values for a specific group during query execution.

fn state_type( &self, _return_type: &DataType ) -> Result<Vec<DataType>, DataFusionError>

Return the type used to serialize the Accumulator’s intermediate state. See Accumulator::state() for more details

impl Debug for SimpleAggregateUDF

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

Formats the value using the given formatter.