Function apply_predicate

nodedb/src/engine/graph/pattern/executor/predicates.rs:11–93

Apply a WHERE predicate to filter rows.

(
    rows: &[BindingRow],
    predicate: &WherePredicate,
    csr: &CsrIndex,
    edge_store: &EdgeStore,
    _frontier_bitmap: Option<&nodedb_types::SurrogateBitmap>,
)

/// Apply a WHERE predicate to filter rows.
pub(super) fn apply_predicate(
    rows: &[BindingRow],
    predicate: &WherePredicate,
    csr: &CsrIndex,
    edge_store: &EdgeStore,
    _frontier_bitmap: Option<&nodedb_types::SurrogateBitmap>,
) -> Result<Vec<BindingRow>, crate::Error> {
    match predicate {
        WherePredicate::Equals {
            binding,
            field,
            value,
        } => {
            if field.is_empty() {
                Ok(rows
                    .iter()
                    .filter(|row| row.get(binding).is_some_and(|v| v == value))
                    .cloned()
                    .collect())
            } else {
                Ok(rows
                    .iter()
                    .filter(|row| {
                        if let Some(node_id) = row.get(binding) {
                            check_property(edge_store, node_id, field, value)
                        } else {
                            false
                        }
                    })
                    .cloned()
                    .collect())
            }
        }

        WherePredicate::Comparison {
            binding,
            field,
            op,
            value,
        } => {
            let _ = (binding, field, op, value);
            Ok(rows.to_vec())
        }

        WherePredicate::NotExists { sub_pattern } => {
            let mut result = Vec::new();
            // NOT EXISTS sub-patterns run in their own local state: any
            // truncation inside the sub-query would make the anti-join
            // unsound (a truncated "empty" isn't really empty), so we
            // instead propagate truncation to the outer query via the
            // top-level `ExecutionState` that the caller of
            // `apply_predicate` already tracks. Here we keep a throwaway
            // local state and inspect it.
            for row in rows {
                let mut sub_state = ExecutionState::default();
                // NOT EXISTS sub-patterns check structural connectivity
                // against already-bound variables — no anchor enumeration
                // occurs, so the frontier bitmap does not apply here.