Struct Scan 

pub struct Scan { /* private fields */ }

Runs a plan over a list of splits.

The plan runs as one stage under each split’s selection.

Up to with_max_active splits are compiled at once, in order, so reads of later splits are in flight while earlier ones compute.

Implementations

impl Scan

pub fn try_new( session: VortexSession, plan: PlanRef, splits: Vec<Split>, ) -> VortexResult<Self>

A scan of plan over splits, with one split active at a time.

Counts, from the plan, how often each split will read each segment, so segments read more than once are decoded once. Builds no pipeline and issues no read.

pub fn with_max_active(self, max_active: usize) -> Self

Runs up to max_active splits at once.

pub fn with_row_offset(self, row_offset: u64) -> Self

Sets the global row index of plan row zero, which row-index plans add to their rows.

pub fn with_value_cache(self, values: ValueCache) -> Self

Shares whole values, such as dictionary values, with the other scans given values.

pub fn step(&mut self) -> VortexResult<Turn>

Runs pipelines until the owner has something to do.

pub fn deliver(&mut self, read: ReadId, bytes: BufferHandle) -> VortexResult<()>

Delivers the bytes of a read step returned.

Trait Implementations

impl Debug for Scan

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

Formats the value using the given formatter.