Trait datafusion_physical_expr::window::BuiltInWindowFunctionExpr

source · [−]
pub trait BuiltInWindowFunctionExpr: Send + Sync + Debug {
    fn as_any(&self) -> &dyn Any;
    fn field(&self) -> Result<Field>;
    fn expressions(&self) -> Vec<Arc<dyn PhysicalExpr>>ⓘNotable traits for Vec<u8, A>impl<A> Write for Vec<u8, A>where
    A: Allocator,;
    fn create_evaluator(
        &self,
        batch: &RecordBatch
    ) -> Result<Box<dyn PartitionEvaluator>>;

    fn name(&self) -> &str { ... }
}
Expand description

A window expression that is a built-in window function.

Note that unlike aggregation based window functions, built-in window functions normally ignore window frame spec, with the exception of first_value, last_value, and nth_value.

Required Methods

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

the field of the final result of this aggregation.

expressions that are passed to the Accumulator. Single-column aggregations such as sum return a single value, others (e.g. cov) return many.

Create built-in window evaluator with a batch

Provided Methods

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

Implementors