Struct StructuralPrimitiveFieldScheduler 

pub struct StructuralPrimitiveFieldScheduler { /* private fields */ }

A scheduler for a leaf node

Here we look at the layout of the various pages and delegate scheduling to a scheduler appropriate for the layout of the page.

Implementations

impl StructuralPrimitiveFieldScheduler

pub fn try_new( column_info: &ColumnInfo, decompressors: &dyn DecompressionStrategy, cache_repetition_index: bool, target_field: &Field, ) -> Result<Self>

👎Deprecated since 13.0.0:

builds every page scheduler eagerly; use try_new_lazy

Creates the scheduler and builds every page scheduler up front.

This pays for all pages of the column on every read. Prefer Self::try_new_lazy, which builds only the pages a read touches.

pub fn try_new_lazy( column_info: Arc<ColumnInfo>, decompressors: Arc<dyn DecompressionStrategy>, cache_repetition_index: bool, target_field: &Field, ) -> Result<Self>

Creates the scheduler without building any page schedulers.

Only the per-page row boundaries are computed here. Page schedulers are built in StructuralFieldScheduler::initialize for the pages the requested ranges touch (or for every page when no ranges are given), so a small read from a column with many pages stays cheap.

Trait Implementations

impl Debug for StructuralPrimitiveFieldScheduler

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

Formats the value using the given formatter.

impl StructuralFieldScheduler for StructuralPrimitiveFieldScheduler

fn initialize<'a>( &'a mut self, requested_ranges: Option<&'a [Range<u64>]>, _filter: &'a FilterExpression, context: &'a SchedulerContext, ) -> BoxFuture<'a, Result<()>>

Loads the per-page metadata this column needs before scheduling.

fn schedule_ranges<'a>( &'a self, ranges: &[Range<u64>], _filter: &FilterExpression, ) -> Result<Box<dyn StructuralSchedulingJob + 'a>>