Enum datafusion_expr::groups_accumulator::EmitTo

pub enum EmitTo {
    All,
    First(usize),
}

Describes how many rows should be emitted during grouping.

Variants

All

Emit all groups

First(usize)

Emit only the first n groups and shift all existing group indexes down by n.

For example, if n=10, group_index 0, 1, ... 9 are emitted and group indexes ’10, 11, 12, ... become 0, 1, 2, ....

Implementations

impl EmitTo

pub fn take_needed<T>(&self, v: &mut Vec<T>) -> Vec<T>

Removes the number of rows from v required to emit the right number of rows, returning a Vec with elements taken, and the remaining values in v.

This avoids copying if Self::All

Trait Implementations

impl Clone for EmitTo

fn clone(&self) -> EmitTo

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for EmitTo

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

Formats the value using the given formatter.

impl Copy for EmitTo