Enum OperatorStorage 

pub enum OperatorStorage {
    Memory,
    SqliteSpill,
}

Where stateful operators (take / cap / reduce) keep their scratch state.

The graph’s [StorageFactory] decides this once, at construction, for every operator the engine’s pipelines build. Both backends are equivalent in result — the SQLite-backed OpStorage agrees with MemoryStorage op-for-op — so the choice is purely an operational memory/throughput trade-off.

Variants

Memory

In-process BTreeMap scratch state (the default). Fastest, but the working set is bounded by RAM.

SqliteSpill

Spill operator state to a private, on-disk temporary SQLite database (one per engine, journal/sync off, exclusive locking — see [DatabaseStorage::new_temp_file]). Lets operator state grow past RAM at the cost of per-op SQLite calls; the scratch DB is deleted when the engine drops.

Trait Implementations

impl Clone for OperatorStorage

fn clone(&self) -> OperatorStorage

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for OperatorStorage

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

Formats the value using the given formatter.

impl Default for OperatorStorage

fn default() -> OperatorStorage

Returns the “default value” for a type.

impl PartialEq for OperatorStorage

fn eq(&self, other: &OperatorStorage) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl Copy for OperatorStorage

impl Eq for OperatorStorage

impl StructuralPartialEq for OperatorStorage