Struct datafusion_expr::window_frame::WindowFrame

pub struct WindowFrame {
    pub units: WindowFrameUnits,
    pub start_bound: WindowFrameBound,
    pub end_bound: WindowFrameBound,
}

The frame-spec determines which output rows are read by an aggregate window function.

The ending frame boundary can be omitted (if the BETWEEN and AND keywords that surround the starting frame boundary are also omitted), in which case the ending frame boundary defaults to CURRENT ROW.

Fields

units: WindowFrameUnits

A frame type - either ROWS, RANGE or GROUPS

start_bound: WindowFrameBound

A starting frame boundary

end_bound: WindowFrameBound

An ending frame boundary

Implementations

impl WindowFrame

pub fn new(has_order_by: bool) -> Self

Creates a new, default window frame (with the meaning of default depending on whether the frame contains an ORDER BY clause.

pub fn reverse(&self) -> Self

Get reversed window frame. For example 3 ROWS PRECEDING AND 2 ROWS FOLLOWING –> 2 ROWS PRECEDING AND 3 ROWS FOLLOWING

Trait Implementations

impl Clone for WindowFrame

fn clone(&self) -> WindowFrame

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for WindowFrame

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

Formats the value using the given formatter.

impl Display for WindowFrame

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

Formats the value using the given formatter.

impl Hash for WindowFrame

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

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<WindowFrame> for WindowFrame

fn eq(&self, other: &WindowFrame) -> 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 TryFrom<WindowFrame> for WindowFrame

type Error = DataFusionError

The type returned in the event of a conversion error.

fn try_from(value: WindowFrame) -> Result<Self>

Performs the conversion.

impl Eq for WindowFrame

impl StructuralEq for WindowFrame

impl StructuralPartialEq for WindowFrame