Struct BasicPageScheduler

pub struct BasicPageScheduler { /* private fields */ }

A physical scheduler for “basic” fields. These are fields that have an optional validity bitmap and some kind of values buffer.

No actual decoding happens here, we are simply aggregating the two buffers.

If everything is null then there are no data buffers at all.

Implementations

impl BasicPageScheduler

pub fn new_nullable( validity_decoder: Box<dyn PageScheduler>, values_decoder: Box<dyn PageScheduler>, ) -> Self

Creates a new instance that expects a validity bitmap

pub fn new_non_nullable(values_decoder: Box<dyn PageScheduler>) -> Self

Create a new instance that does not need a validity bitmap because no item is null

pub fn new_all_null() -> Self

Create a new instance where all values are null

It may seem strange we need values_decoder here but Arrow requires that value buffers still be allocated / sized even if everything is null. So we need the value decoder to calculate the capacity of the garbage buffer.

Trait Implementations

impl Debug for BasicPageScheduler

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

Formats the value using the given formatter.

impl PageScheduler for BasicPageScheduler

fn schedule_ranges( &self, ranges: &[Range<u64>], scheduler: &Arc<dyn EncodingsIo>, top_level_row: u64, ) -> BoxFuture<'static, Result<Box<dyn PrimitivePageDecoder>>>

Schedules a batch of I/O to load the data needed for the requested ranges