Enum EngineError 

#[non_exhaustive]
pub enum EngineError {
    Parse(ParseError),
    Storage(StorageError),
    Eval(EvalError),
    Unsupported(String),
    TransactionAlreadyOpen,
    NoActiveTransaction,
    WriteRequired,
    RowLimitExceeded(usize),
    Cancelled,
}

All errors the engine can return.

Marked #[non_exhaustive] from v7.5.0 onward: external match must include a _ arm so new variants in subsequent v7.x releases are not breaking changes.

Variants (Non-exhaustive)

Non-exhaustive enums could have additional variants added in future. Therefore, when matching against variants of non-exhaustive enums, an extra wildcard arm must be added to account for any future variants.

Parse(ParseError)

Storage(StorageError)

Eval(EvalError)

Unsupported(String)

Front-end accepted a construct that the v0.x executor doesn’t support.

TransactionAlreadyOpen

BEGIN while another transaction is already open.

NoActiveTransaction

COMMIT / ROLLBACK with no active transaction.

WriteRequired

v4.0 sentinel: execute_readonly got a statement that mutates engine state (INSERT / CREATE / BEGIN / COMMIT / …). The caller should retake the write lock and dispatch through execute(&mut self) instead.

RowLimitExceeded(usize)

v4.2: a SELECT would have returned more rows than the configured max_query_rows cap. Carries the cap.

Cancelled

v4.5: cooperative cancellation — the host (server’s per-query watchdog) set the cancel flag while a long-running SELECT / UPDATE / DELETE was scanning rows. The partial work is discarded; the caller should surface this as a timeout to the client.

Trait Implementations

impl Clone for EngineError

fn clone(&self) -> EngineError

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for EngineError

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

Formats the value using the given formatter.

impl Display for EngineError

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

Formats the value using the given formatter.

impl From<EvalError> for EngineError

fn from(e: EvalError) -> Self

Converts to this type from the input type.

impl From<ParseError> for EngineError

fn from(e: ParseError) -> Self

Converts to this type from the input type.

impl From<StorageError> for EngineError

fn from(e: StorageError) -> Self

Converts to this type from the input type.

impl PartialEq for EngineError

fn eq(&self, other: &EngineError) -> 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 StructuralPartialEq for EngineError