Struct IncrementalViewMaintainer 

pub struct IncrementalViewMaintainer { /* private fields */ }

Manages a collection of MaterializedViews and propagates delta changes.

Workflow

1. Call register_view to create a new view from a ViewDefinition and an initial result set.
2. Call apply_delta (or queue_change + flush_changes) whenever the underlying triple store changes.
3. Invalidated views can be re-evaluated by the caller and refreshed with new rows via internal access to the views map (or by replacing the whole view).

Implementations

impl IncrementalViewMaintainer

pub fn new() -> Self

Create an empty maintainer.

pub fn register_view(&mut self, def: ViewDefinition, initial_rows: Vec<ViewRow>)

Register a named view.

If a view with the same definition.name already exists it is replaced.

pub fn apply_delta(&mut self, change: DeltaChange) -> Vec<String>

Apply a single DeltaChange immediately.

Returns the names of views that were invalidated (i.e. whose dependencies include the changed predicate or are empty). Views that are already stale are not returned again (no-duplicate semantics).

pub fn invalidate_view(&mut self, name: &str)

Mark a view as stale by name.

Does nothing if the view does not exist.

pub fn get_view(&self, name: &str) -> Option<&MaterializedView>

Return an immutable reference to a view.

pub fn list_views(&self) -> Vec<&str>

Return the names of all registered views, in unspecified order.

pub fn affected_views(&self, predicate: &str) -> Vec<&str>

Return the names of all views that depend on predicate.

This includes views with an empty dependencies list (universal dependency).

pub fn queue_change(&mut self, change: DeltaChange)

Push a change onto the internal queue for later batch processing.

pub fn flush_changes(&mut self) -> HashMap<String, usize>

Apply all queued changes at once and clear the queue.

Returns a map of view_name → rows_changed. Because this implementation uses a mark-stale strategy, invalidated views are reported with 0 changed rows. Views that were not affected are not included in the returned map.

pub fn view_count(&self) -> usize

Return the number of registered views.

pub fn total_rows(&self) -> usize

Return the total number of cached rows across all non-stale views.

Trait Implementations

impl Default for IncrementalViewMaintainer

fn default() -> Self

Returns the “default value” for a type.