Struct ScanBuilder

pub struct ScanBuilder<A> { /* private fields */ }

A struct for building a scan operation.

Implementations

impl<A> ScanBuilder<A>

where A: 'static + Send,

pub fn with_filter(self, filter: Arc<dyn VortexExpr>) -> ScanBuilder<A>

pub fn with_some_filter( self, filter: Option<Arc<dyn VortexExpr>>, ) -> ScanBuilder<A>

pub fn with_projection(self, projection: Arc<dyn VortexExpr>) -> ScanBuilder<A>

pub fn with_row_range(self, row_range: Range<u64>) -> ScanBuilder<A>

pub fn with_some_row_range( self, row_range: Option<Range<u64>>, ) -> ScanBuilder<A>

pub fn with_selection(self, selection: Selection) -> ScanBuilder<A>

pub fn with_row_indices(self, row_indices: Buffer<u64>) -> ScanBuilder<A>

pub fn with_split_by(self, split_by: SplitBy) -> ScanBuilder<A>

pub fn with_concurrency(self, concurrency: usize) -> ScanBuilder<A>

The number of row splits to make progress on concurrently, must be greater than 0.

pub fn with_metrics(self, metrics: VortexMetrics) -> ScanBuilder<A>

pub fn map<B>( self, map_fn: impl Fn(A) -> Result<B, VortexError> + Send + Sync + 'static, ) -> ScanBuilder<B>

where B: 'static,

Map each split of the scan. The function will be run on the spawned task.

pub fn dtype(&self) -> Result<DType, VortexError>

Returns the output DType of the scan.

pub fn build( self, ) -> Result<Vec<impl Future<Output = Result<Option<A>, VortexError>>>, VortexError>

Constructs a task per row split of the scan, returned as a vector of futures.

pub fn into_stream( self, ) -> Result<impl Stream<Item = Result<A, VortexError>> + 'static, VortexError>

Returns a stream over the scan objects.

impl ScanBuilder<Arc<dyn Array>>

pub fn new(layout_reader: Arc<dyn LayoutReader>) -> ScanBuilder<Arc<dyn Array>>

pub fn map_to_record_batch( self, schema: Arc<Schema>, ) -> ScanBuilder<RecordBatch>

Map the scan into a stream of Arrow RecordBatch.

pub fn into_array_stream( self, ) -> Result<impl ArrayStream + 'static, VortexError>

Returns a stream over the scan with each CPU task polled on the current thread as per the behaviour of futures::stream::Buffered.

pub fn into_array_iter( self, ) -> Result<impl ArrayIterator + 'static, VortexError>

Returns a blocking iterator over the scan.

All work will be performed on the current thread, with tasks interleaved per the configured concurrency. Any configured executor will be ignored.