Struct ProgressHandle 

pub struct ProgressHandle { /* private fields */ }

A handle for polling the progress of a long-running query.

A Connection is not Sync, so the thread running the query owns it for the duration. This handle is Send + Sync, cheap to clone, and does not block the query.

Once the connection is closed or dropped, ProgressHandle::query_progress reports an unavailable snapshot rather than failing, matching how crate::InterruptHandle becomes a no-op. That makes a closed connection indistinguishable from a query DuckDB cannot estimate, so a poller deciding whether to keep polling should ask ProgressHandle::is_connected.

See the module docs for an example.

Implementations

impl ProgressHandle

pub fn query_progress(&self) -> QueryProgress

Snapshot the progress of the query running on the connection this handle came from.

pub fn is_connected(&self) -> bool

Whether the connection this handle came from is still open.

Distinguishes a closed connection from a query with no estimate, since ProgressHandle::query_progress reports both as unavailable. This is a hint, not a guarantee: the connection may close immediately after it returns true.

Trait Implementations

impl Clone for ProgressHandle

fn clone(&self) -> Self

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for ProgressHandle

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

Formats the value using the given formatter.