Enum QueryError 

pub enum QueryError {
    TableNotFound(String),
    ColumnNotFound {
        table: String,
        column: String,
    },
    TypeError(String),
    JoinLimitExceeded,
    NestedLoopPairLimitExceeded {
        left_rows: usize,
        right_rows: usize,
        limit: usize,
    },
    SortLimitExceeded,
    MemoryLimitExceeded {
        limit_bytes: usize,
        requested_bytes: usize,
    },
    Parse(String),
    IndexError(String),
    ViewError(String),
    StorageError(String),
    ReadonlyNeedsWrite,
    ReadonlyMode,
    Timeout {
        timeout_ms: u64,
    },
    Cancelled,
    Execution(String),
}

Typed error enum for query execution failures.

Replaces the previous Result<QueryResult, String> pattern with structured variants that callers can programmatically match on. The From<String> impl enables gradual migration: existing Err(format!(...)) sites continue to compile via ? propagation.

Display strings are wire-visible behavior: the server’s egress sanitization prefix-matches them and clients assert on them. Every message is pinned byte-exact by tests/error_display.rs; do not reword one without updating that suite deliberately.

Variants

TableNotFound(String)

Table does not exist.

ColumnNotFound

Column does not exist on table.

Fields

table: String

column: String

TypeError(String)

Type mismatch in expression.

JoinLimitExceeded

Join result exceeded MAX_JOIN_ROWS.

NestedLoopPairLimitExceeded

A fallback nested-loop join would evaluate more candidate pairs than the measured safety cap.

Fields

left_rows: usize

right_rows: usize

limit: usize

SortLimitExceeded

Sort exceeded MAX_SORT_ROWS.

MemoryLimitExceeded

Per-query memory budget exceeded during materialization (sort buffer, join build side, GROUP BY hash table, or IN-list). Returned cleanly so the server process is never OOM-killed by a crafted query.

Fields

limit_bytes: usize

requested_bytes: usize

Parse(String)

Parse error (wraps parser error).

IndexError(String)

Index-related error.

ViewError(String)

View-related error.

StorageError(String)

WAL or I/O error.

ReadonlyNeedsWrite

Readonly path needs write lock (internal sentinel). The server intercepts this variant before Display, so the sentinel string must never cross the wire.

ReadonlyMode

The engine was opened read-only (snapshot serving) and the statement requires a writer. Unlike QueryError::ReadonlyNeedsWrite, this is a terminal error with an operator-facing message: there is no writer to escalate to in this mode.

Timeout

The per-query deadline elapsed before execution finished. Returned as a clean early-return from an unbounded executor loop so the query releases its locks instead of running to completion. timeout_ms is the configured per-query timeout.

Fields

timeout_ms: u64

Cancelled

Execution was cancelled cooperatively (e.g. the issuing client disconnected). Like QueryError::Timeout, a clean early-return.

Execution(String)

Generic execution error (catch-all for migration).

Trait Implementations

impl Clone for QueryError

fn clone(&self) -> QueryError

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for QueryError

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

Formats the value using the given formatter.

impl Display for QueryError

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

Formats the value using the given formatter.

impl Error for QueryError

fn source(&self) -> Option<&(dyn Error + 'static)>

Returns the lower-level source of this error, if any.

fn description(&self) -> &str

👎Deprecated since 1.42.0:

use the Display impl or to_string()

fn cause(&self) -> Option<&dyn Error>

👎Deprecated since 1.33.0:

replaced by Error::source, which can support downcasting

fn provide<'a>(&'a self, request: &mut Request<'a>)

🔬This is a nightly-only experimental API. (error_generic_member_access)

Provides type-based access to context intended for error reports.

impl From<&str> for QueryError

fn from(s: &str) -> Self

Converts to this type from the input type.

impl From<String> for QueryError

fn from(s: String) -> Self

Converts to this type from the input type.

impl PartialEq for QueryError

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

Equality operator ==.

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

Inequality operator !=.

impl StructuralPartialEq for QueryError