Struct WindowFrameStateGroups 

pub struct WindowFrameStateGroups {
    pub group_end_indices: VecDeque<(Vec<ScalarValue>, usize)>,
    pub current_group_idx: usize,
}

This structure encapsulates all the state information we require as we scan groups of data while processing window frames.

Fields

group_end_indices: VecDeque<(Vec<ScalarValue>, usize)>

A tuple containing group values and the row index where the group ends. Example: [[1, 1], [1, 1], [2, 1], [2, 1], …] would correspond to [([1, 1], 2), ([2, 1], 4), …].

current_group_idx: usize

The group index to which the row index belongs.

Implementations

impl WindowFrameStateGroups

fn calculate_range( &mut self, window_frame: &Arc<WindowFrame>, range_columns: &[ArrayRef], length: usize, idx: usize, ) -> Result<Range<usize>>

fn calculate_index_of_row<const SIDE: bool, const SEARCH_SIDE: bool>( &mut self, range_columns: &[ArrayRef], idx: usize, delta: Option<&ScalarValue>, length: usize, ) -> Result<usize>

This function does the heavy lifting when finding range boundaries. It is meant to be called twice, in succession, to get window frame start and end indices (with SIDE supplied as true and false, respectively). Generic argument SEARCH_SIDE determines the sign of delta (where true/false represents negative/positive respectively).

Trait Implementations

impl Clone for WindowFrameStateGroups

fn clone(&self) -> WindowFrameStateGroups

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for WindowFrameStateGroups

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

Formats the value using the given formatter.

impl Default for WindowFrameStateGroups

fn default() -> WindowFrameStateGroups

Returns the “default value” for a type.