Struct FilterIndex 

pub struct FilterIndex { /* private fields */ }

A filter over physical row IDs, backed by a Roaring Bitmap.

Construct from matching row IDs or from an Arrow BooleanArray, then apply to a PermutationIndex to get a filtered selection vector.

Implementations

impl FilterIndex

pub fn from_ids(ids: impl IntoIterator<Item = u32>) -> Self

Construct from an iterator of matching physical row IDs.

pub fn from_boolean_array(arr: &BooleanArray) -> Self

Construct from an Arrow BooleanArray where true = passes filter.

Null values are treated as false (do not pass filter).

pub fn len(&self) -> u64

Number of rows passing the filter.

pub fn is_empty(&self) -> bool

Whether no rows pass the filter.

pub fn contains(&self, id: u32) -> bool

Check whether a specific physical row ID passes the filter.

pub fn apply_to_permutation( &self, permutation: &PermutationIndex, ) -> PermutationIndex

Apply this filter to a sorted permutation, returning a new PermutationIndex containing only the permuted rows that pass the filter, in sort order.

This is the core composition operation: sorted_and_filtered = filter.apply_to_permutation(&sorted)

Processes in chunks to avoid reading entire mmap indices at once. Time: O(n) where n = permutation length, with O(1) membership checks via the Roaring Bitmap.

pub fn intersection(&self, other: &FilterIndex) -> FilterIndex

Intersect two filters (AND semantics).

pub fn union(&self, other: &FilterIndex) -> FilterIndex

Union two filters (OR semantics).

pub fn negate(&self, total_rows: u32) -> FilterIndex

Negate filter within a universe of total_rows physical rows.

Returns a filter containing all rows in [0, total_rows) that are NOT in the current filter. Uses insert_range for O(containers) universe construction instead of O(elements) iteration.

pub fn difference(&self, other: &FilterIndex) -> FilterIndex

Set difference: rows in self but not in other.

Equivalent to self ∩ ¬other, but without allocating the negation.

pub fn into_boolean_array(&self, total_rows: u32) -> BooleanArray

Convert to a BooleanArray of length total_rows.

true at position i means physical row i passes the filter.

pub fn iter(&self) -> impl Iterator<Item = u32> + '_

Iterate over matching physical row IDs in ascending order.

Trait Implementations

impl Clone for FilterIndex

fn clone(&self) -> FilterIndex

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for FilterIndex

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

Formats the value using the given formatter.