Struct TidBitmap 

pub struct TidBitmap { /* private fields */ }

A sparse, sorted set of row IDs backed by a Roaring bitmap. Row IDs are u32 because Roaring’s API is u32-native; tables with more than 4 billion rows need to partition by another dimension (typically segment id) and use multiple bitmaps.

Implementations

impl TidBitmap

pub fn new() -> Self

Create an empty bitmap with the default 32 MB cap.

pub fn with_cap_bytes(cap_bytes: usize) -> Self

Create an empty bitmap with a custom cap (bytes). Use 0 to disable the cap entirely — useful for tests and in-memory benchmarks.

pub fn insert(&mut self, tid: u32) -> Result<bool, BitmapError>

Insert a row ID. Returns BitmapError::TooLarge if the resulting size exceeds the configured cap; the row is NOT inserted in that case so the caller can recover by switching strategies.

pub fn extend_from_iter( &mut self, iter: impl IntoIterator<Item = u32>, ) -> Result<usize, BitmapError>

Bulk insert from any iterator of row IDs. Stops on the first cap violation and returns the number of IDs that were successfully inserted before the cap was hit.

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

Returns true when the bitmap contains the given row ID. O(log n) lookup — Roaring does block search internally.

pub fn len(&self) -> u64

Number of row IDs in the bitmap.

pub fn is_empty(&self) -> bool

True when the bitmap holds no row IDs.

pub fn intersect_with(&mut self, other: &TidBitmap)

In-place AND with another bitmap. Used by the planner’s WHERE a = 1 AND b = 2 rewrite: lookup each side, AND the results.

pub fn union_with(&mut self, other: &TidBitmap)

In-place OR with another bitmap. Used by WHERE a OR b patterns and IN list expansion.

pub fn difference_with(&mut self, other: &TidBitmap)

In-place ANDNOT — remove every row ID also present in other. Used by WHERE a AND NOT b patterns and EXCEPT queries.

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

Iterate row IDs in sorted ascending order. The heap fetcher uses this to read pages sequentially.

pub fn into_sorted_vec(self) -> Vec<u32>

Drain all row IDs in sorted ascending order, consuming the bitmap. Equivalent to iter().collect() but releases the inner storage as soon as iteration completes.

pub fn group_by_page(&self, rows_per_page: u32) -> Vec<(u32, Vec<u32>)>

Group row IDs by their containing page number. Returns a vector of (page_id, Vec<row_within_page>) pairs sorted by page_id ascending. The heap fetcher reads each page once and extracts every matching row in a single I/O.

rows_per_page is the table-specific constant — for reddb’s default 8 KB pages with ~64-byte rows it’s roughly 128, but call sites pass the exact value from their schema metadata.

pub fn union_cardinality(&self, other: &TidBitmap) -> u64

Cardinality of the union with another bitmap, computed without materialising the union itself. Used by the planner’s cost estimator to compare AND vs OR rewrites without paying the merge cost.

pub fn intersection_cardinality(&self, other: &TidBitmap) -> u64

Cardinality of the intersection with another bitmap, also without materialising the result.

Trait Implementations

impl Clone for TidBitmap

fn clone(&self) -> TidBitmap

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for TidBitmap

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

Formats the value using the given formatter.

impl Default for TidBitmap

fn default() -> TidBitmap

Returns the “default value” for a type.