Struct TxId 

pub struct TxId(pub u64);

v4.5 cooperative cancellation token. A long-running SELECT / UPDATE / DELETE checks is_cancelled at row-loop checkpoints and bails with EngineError::Cancelled. The host (spg-server) creates an AtomicBool per query, spawns a watchdog thread that sets it after SPG_QUERY_TIMEOUT_MS, and passes it via execute_with_cancel / execute_readonly_with_cancel.

CancelToken::none() is a no-op — used by the legacy execute and execute_readonly entry points so existing callers don’t change. v4.41.1 opaque transaction handle. Returned by Engine::alloc_tx_id, threaded through Engine::execute_in so dispatch can identify which in-flight TX a statement belongs to. IMPLICIT_TX is the reserved slot every legacy caller — engine self-tests, spg-cli, spg-embedded, startup replay — implicitly uses through the unchanged Engine::execute(sql) API. v4.41.1 keeps at most one active slot at runtime (dispatch holds engine.write() across the wrap, same as v4.34); the map shape is here to let v4.42 turn on N in-flight implicit TXs without reshuffling the engine internals.

Tuple Fields

0: u64

Trait Implementations

impl Clone for TxId

fn clone(&self) -> TxId

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Copy for TxId

impl Debug for TxId

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

Formats the value using the given formatter.

impl Eq for TxId

impl Hash for TxId

fn hash<__H: Hasher>(&self, state: &mut __H)

Feeds this value into the given Hasher.

fn hash_slice<H>(data: &[Self], state: &mut H)

where H: Hasher, Self: Sized,

Feeds a slice of this type into the given Hasher.

impl Ord for TxId

fn cmp(&self, other: &TxId) -> Ordering

This method returns an Ordering between self and other.

fn max(self, other: Self) -> Self

where Self: Sized,

Compares and returns the maximum of two values.

fn min(self, other: Self) -> Self

where Self: Sized,

Compares and returns the minimum of two values.

fn clamp(self, min: Self, max: Self) -> Self

where Self: Sized,

Restrict a value to a certain interval.

impl PartialEq for TxId

fn eq(&self, other: &TxId) -> 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 PartialOrd for TxId

fn partial_cmp(&self, other: &TxId) -> Option<Ordering>

This method returns an ordering between self and other values if one exists.

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

Tests less than (for self and other) and is used by the < operator.

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

Tests less than or equal to (for self and other) and is used by the <= operator.

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

Tests greater than (for self and other) and is used by the > operator.

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

Tests greater than or equal to (for self and other) and is used by the >= operator.

impl StructuralPartialEq for TxId