Function optimize

nodedb-sql/src/optimizer/point_get.rs:8–37

If a Scan has a single equality filter on the primary key, convert to PointGet.

(plan: SqlPlan)

/// If a Scan has a single equality filter on the primary key, convert to PointGet.
pub fn optimize(plan: SqlPlan) -> SqlPlan {
    match plan {
        SqlPlan::Scan {
            ref collection,
            ref alias,
            ref engine,
            ref filters,
            ref projection,
            ref temporal,
            ..
        } if filters.len() == 1
            && !temporal.is_temporal()
            && !projection
                .iter()
                .any(|p| matches!(p, Projection::Computed { .. })) =>
        {
            if let Some((key_col, key_val)) = extract_pk_equality(&filters[0]) {
                return SqlPlan::PointGet {
                    collection: collection.clone(),
                    alias: alias.clone(),
                    engine: *engine,
                    key_column: key_col,
                    key_value: key_val,
                };
            }
            plan
        }
        _ => plan,
    }
}

/// Extract a simple equality filter on a known PK column.
fn extract_pk_equality(filter: &Filter) -> Option<(String, SqlValue)> {