Struct datafusion::logical_expr::WindowUDF

pub struct WindowUDF {
    pub name: String,
    pub signature: Signature,
    pub return_type: Arc<dyn Fn(&[DataType]) -> Result<Arc<DataType>, DataFusionError> + Send + Sync>,
    pub partition_evaluator_factory: Arc<dyn Fn() -> Result<Box<dyn PartitionEvaluator, Global>, DataFusionError> + Send + Sync>,
}

Logical representation of a user-defined window function (UDWF) A UDWF is different from a UDF in that it is stateful across batches.

See the documetnation on PartitionEvaluator for more details

Fields

name: String

name

signature: Signature

signature

return_type: Arc<dyn Fn(&[DataType]) -> Result<Arc<DataType>, DataFusionError> + Send + Sync>

Return type

partition_evaluator_factory: Arc<dyn Fn() -> Result<Box<dyn PartitionEvaluator, Global>, DataFusionError> + Send + Sync>

Return the partition evaluator

Implementations

impl WindowUDF

pub fn new( name: &str, signature: &Signature, return_type: &Arc<dyn Fn(&[DataType]) -> Result<Arc<DataType>, DataFusionError> + Send + Sync>, partition_evaluator_factory: &Arc<dyn Fn() -> Result<Box<dyn PartitionEvaluator, Global>, DataFusionError> + Send + Sync> ) -> WindowUDF

Create a new WindowUDF

pub fn call( &self, args: Vec<Expr, Global>, partition_by: Vec<Expr, Global>, order_by: Vec<Expr, Global>, window_frame: WindowFrame ) -> Expr

creates a Expr that calls the window function given the partition_by, order_by, and window_frame definition

This utility allows using the UDWF without requiring access to the registry, such as with the DataFrame API.

Trait Implementations

impl Clone for WindowUDF

fn clone(&self) -> WindowUDF

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for WindowUDF

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

Formats the value using the given formatter.

impl Display for WindowUDF

Defines how the WindowUDF is shown to users

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

Formats the value using the given formatter.

impl Hash for WindowUDF

fn hash<H>(&self, state: &mut H)where H: Hasher,

Feeds this value into the given Hasher.

fn hash_slice<H>(data: &[Self], state: &mut H)where H: Hasher, Self: Sized,

Feeds a slice of this type into the given Hasher.

impl PartialEq<WindowUDF> for WindowUDF

fn eq(&self, other: &WindowUDF) -> bool

This method tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

This method tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl Eq for WindowUDF