Struct WindowSpec 

pub struct WindowSpec {
    pub partition: Slice,
    pub order: Slice,
    pub unit: WindowUnit,
    pub start: WindowBound,
    pub end: WindowBound,
    pub exclude: WindowExclude,
}

Everything inside the parentheses of an OVER.

A named window is resolved here rather than downstream, because the resolution is a parser question on the reference binary: a reference to a window nobody defined is a Parser Error there, and a view written with OVER w comes back out of the catalog with the definition inlined. So nothing after the transform ever sees a name, and there is no window clause on Select for it to see one in.

Fields

partition: Slice

The PARTITION BY list, as a run of ExprRef, empty when there was no clause.

order: Slice

The ORDER BY list, as a run of OrderItem, empty when there was no clause.

unit: WindowUnit

Which of the three units the bounds are measured in.

start: WindowBound

Where the frame starts.

end: WindowBound

Where the frame ends.

exclude: WindowExclude

Which peers the frame drops.

Implementations

impl WindowSpec

pub const DEFAULT_UNIT: WindowUnit = WindowUnit::Range

The frame a window with no frame clause gets, which the standard fixes and DuckDB follows.

pub const DEFAULT_START: WindowBound = WindowBound::UnboundedPreceding

The start a window with no frame clause gets.

pub const DEFAULT_END: WindowBound = WindowBound::CurrentRow

The end a window with no frame clause gets.

pub const fn empty() -> Self

A window with no clauses at all, which is what OVER () means.

pub fn frame_is_default(&self) -> bool

Whether the frame is the one an unwritten frame clause means.

This is what decides whether the frame is printed, which is not a matter of taste: the printed form is the column name a window target gets when the query wrote no alias, so SELECT sum(x) OVER (ORDER BY x) has to be named without a frame in it to agree with the reference binary.

Trait Implementations

impl Clone for WindowSpec

fn clone(&self) -> WindowSpec

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Copy for WindowSpec

impl Debug for WindowSpec

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

Formats the value using the given formatter.

impl Eq for WindowSpec

impl PartialEq for WindowSpec

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

Equality operator ==.

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

Inequality operator !=.

impl StructuralPartialEq for WindowSpec