Struct DataFusionAccumulatorAdapter 

pub struct DataFusionAccumulatorAdapter { /* private fields */ }

Adapts a DataFusion datafusion_expr::Accumulator into LaminarDB’s DynAccumulator trait.

Uses RefCell for interior mutability since DataFusion’s evaluate() and state() require &mut self but LaminarDB’s result_scalar() and serialize() take &self.

Implementations

impl DataFusionAccumulatorAdapter

pub fn new( inner: Box<dyn Accumulator>, column_indices: Vec<usize>, input_types: Vec<DataType>, function_name: String, factory: Arc<DataFusionAggregateFactory>, ) -> Self

Creates a new adapter wrapping a DataFusion accumulator.

pub fn function_name(&self) -> &str

Returns the wrapped function name.

Trait Implementations

impl Debug for DataFusionAccumulatorAdapter

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

Formats the value using the given formatter.

impl DynAccumulator for DataFusionAccumulatorAdapter

fn add_event(&mut self, event: &Event)

Adds an event to the accumulator.

fn merge_dyn(&mut self, other: &dyn DynAccumulator)

Merges another accumulator of the same type into this one.

fn result_scalar(&self) -> ScalarResult

Returns the current aggregate result.

fn is_empty(&self) -> bool

Returns true if no values have been accumulated.

fn clone_box(&self) -> Box<dyn DynAccumulator>

Creates a boxed clone of this accumulator.

fn serialize(&self) -> Vec<u8>

Serializes the accumulator state to bytes (for checkpointing).

fn result_field(&self) -> Field

Returns the Arrow field descriptor for this accumulator’s output.

fn type_tag(&self) -> &'static str

Returns a type tag for deserialization dispatch.

fn as_any(&self) -> &dyn Any

Returns self as Any for downcasting (used by DataFusion bridge).

impl Send for DataFusionAccumulatorAdapter