Enum ColumnMapping

enum ColumnMapping {
    Small(SmallVec<[i32; 8]>),
    Large(HashMap<i32, usize>),
}

A mapping from column id to the index of the column in the schema.

Variants

Small(SmallVec<[i32; 8]>)

For small number of columns, use linear search with SmallVec. This ensures no heap allocation.

Large(HashMap<i32, usize>)

For larger number of columns, build a HashMap for faster lookup.

Implementations

impl ColumnMapping

fn new(column_ids: impl ExactSizeIterator<Item = ColumnId>) -> Self

fn get(&self, id: i32) -> Option<usize>

Trait Implementations

impl Clone for ColumnMapping

fn clone(&self) -> ColumnMapping

Returns a copy of the value.

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

Performs copy-assignment from source.