Struct Db 

pub struct Db { /* private fields */ }

An immutable value of a database at one basis transaction and time view.

Implementations

impl Db

pub fn new(schema: Schema) -> Self

Creates an empty database with the supplied schema.

pub fn with_naming(self, idents: Idents, interner: KeywordInterner) -> Self

Attaches ident and keyword naming registries, returning the named value.

pub const fn basis_t(&self) -> u64

Current transaction basis.

pub const fn schema(&self) -> &Schema

Schema at this basis.

pub fn idents(&self) -> &Idents

Ident registry.

pub fn interner(&self) -> &KeywordInterner

Keyword interner used by keyword values in this database.

pub const fn view(&self) -> DbView

The time view this value presents.

pub fn recorded_datoms(&self) -> &[Datom]

Every recorded assertion and retraction, in transaction order.

pub fn as_of(&self, t: u64) -> Self

Returns the as-of view at basis t: facts as they stood then.

pub fn since(&self, t: u64) -> Self

Returns the since view: only live facts added after t.

pub fn history(&self) -> Self

Returns the history view: all assertions and retractions ever.

pub fn tx_range(&self, start: u64, end: Option<u64>) -> Vec<(u64, Vec<Datom>)>

Groups recorded datoms by transaction over the half-open range [start, end).

pub fn datoms(&self) -> Vec<Datom>

Returns this view’s facts, deterministically ordered by EAVT.

pub fn datoms_at(&self, order: IndexOrder) -> impl Iterator<Item = &Datom>

Iterates this view’s datoms in one index order.

AVET covers only indexed/unique attributes and VAET only reference values, mirroring Datomic’s covering-index composition.

pub fn datoms_prefix<'a>( &'a self, order: IndexOrder, prefix: &'a [u8], ) -> impl Iterator<Item = &'a Datom>

Iterates datoms whose key in order starts with prefix.

pub fn seek_datoms<'a>( &'a self, order: IndexOrder, start: &[u8], ) -> impl Iterator<Item = &'a Datom>

Iterates datoms in order starting from the first key at or after start.

pub fn index_range<'a>( &'a self, a: AttrId, start: Option<&Value>, end: Option<&'a Value>, ) -> impl Iterator<Item = &'a Datom>

Iterates the AVET index for a over the value range [start, end).

Only indexed/unique attributes appear in AVET.

pub fn values(&self, e: EntityId, a: AttrId) -> Vec<Value>

Current values for an entity/attribute pair.

pub fn lookup(&self, a: AttrId, v: &Value) -> Option<EntityId>

Resolves a unique attribute/value pair to its entity.

pub fn with_transaction(&self, t: u64, datoms: &[Datom]) -> Self

Applies a committed record, returning a new database value.

Only meaningful for the current view; time views are read-only.

pub fn stats(&self) -> DbStats

Computes basic statistics over this view’s facts.

pub fn planner_stats(&self) -> &PlannerStats

Planner statistics for this view, built lazily and cached.

Trait Implementations

impl Clone for Db

fn clone(&self) -> Db

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for Db

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

Formats the value using the given formatter.

impl Default for Db

fn default() -> Db

Returns the “default value” for a type.