Struct WindowUDFExpr 

pub struct WindowUDFExpr {
    fun: Arc<WindowUDF>,
    args: Vec<Arc<dyn PhysicalExpr>>,
    name: String,
    input_fields: Vec<FieldRef>,
    is_reversed: bool,
    ignore_nulls: bool,
}

Implements [StandardWindowFunctionExpr] for WindowUDF

Fields

fun: Arc<WindowUDF>

args: Vec<Arc<dyn PhysicalExpr>>

name: String

Display name

input_fields: Vec<FieldRef>

Fields of input expressions

is_reversed: bool

This is set to true only if the user-defined window function expression supports evaluation in reverse order, and the evaluation order is reversed.

ignore_nulls: bool

Set to true if IGNORE NULLS is defined, false otherwise.

Implementations

impl WindowUDFExpr

pub fn fun(&self) -> &Arc<WindowUDF>

Trait Implementations

impl Clone for WindowUDFExpr

fn clone(&self) -> WindowUDFExpr

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for WindowUDFExpr

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

Formats the value using the given formatter.

impl StandardWindowFunctionExpr for WindowUDFExpr

fn as_any(&self) -> &dyn Any

Returns the aggregate expression as Any so that it can be downcast to a specific implementation.

fn field(&self) -> Result<FieldRef>

The field of the final result of evaluating this window function.

fn expressions(&self) -> Vec<Arc<dyn PhysicalExpr>>

Expressions that are passed to the PartitionEvaluator.

fn create_evaluator(&self) -> Result<Box<dyn PartitionEvaluator>>

Create a PartitionEvaluator for evaluating the function on a particular partition.

fn name(&self) -> &str

Human readable name such as "MIN(c2)" or "RANK()". The default implementation returns placeholder text.

fn reverse_expr(&self) -> Option<Arc<dyn StandardWindowFunctionExpr>>

Construct a new [StandardWindowFunctionExpr] that produces the same result as this function on a window with reverse order. The return value of this function is used by the DataFusion optimizer to avoid re-sorting the data when possible.

fn get_result_ordering(&self, schema: &SchemaRef) -> Option<PhysicalSortExpr>

Returns the ordering introduced by the window function, if applicable. Most window functions don’t introduce an ordering, hence the default value is None. Note that this information is used to update ordering equivalences.

fn limit_effect(&self) -> LimitEffect

fn evaluate_args( &self, batch: &RecordBatch, ) -> Result<Vec<Arc<dyn Array>>, DataFusionError>

Evaluate window function’s arguments against the input window batch and return an [ArrayRef].