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RowStream

Struct RowStream 

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pub struct RowStream<'a, S: ConnectionState = Ready> { /* private fields */ }
Expand description

An incrementally streamed result set: rows are read from the network as they are pulled, not buffered up front.

See the module docs for how this differs from QueryStream. Obtain one from Client::query_stream.

Pulling is async (each row may require reading another packet), so this type is consumed via try_next / collect_all rather than the synchronous Iterator that QueryStream offers.

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impl<'a, S: ConnectionState> RowStream<'a, S>

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pub fn columns(&self) -> &[Column]

The columns of the current result set.

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pub fn is_finished(&self) -> bool

Whether the stream has been fully consumed.

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pub async fn try_next(&mut self) -> Result<Option<Row>>

Pull the next row, reading more packets from the connection as needed.

Returns Ok(None) once the response is fully drained — at which point the connection is clean for the next request. A server error token in the stream is surfaced here as Error::Server.

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pub async fn collect_all(self) -> Result<Vec<Row>>

Drain the remaining rows into a vector.

For large result sets prefer try_next — this loads every remaining row into memory at once.

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pub async fn cancel(self) -> Result<()>

Stop the stream early and leave the connection reusable.

Sends an Attention to the server and drains to its acknowledgement so the connection is clean for the next request — the correct way to abandon a large result set you no longer need.

Calling this is optional: simply dropping a partially-read stream is safe but leaves the connection marked in-flight, so a pooled connection is discarded on return and a directly reused client recovers it (with an Attention/drain) on its next request. cancel avoids that discard and reports any error from the cancellation.

Auto Trait Implementations§

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impl<'a, S = Ready> !Freeze for RowStream<'a, S>

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impl<'a, S = Ready> !RefUnwindSafe for RowStream<'a, S>

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impl<'a, S = Ready> !UnwindSafe for RowStream<'a, S>

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impl<'a, S> Send for RowStream<'a, S>
where S: Send,

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impl<'a, S> Sync for RowStream<'a, S>
where S: Sync,

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impl<'a, S> Unpin for RowStream<'a, S>

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impl<'a, S> UnsafeUnpin for RowStream<'a, S>

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where T: 'static + ?Sized,

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