Struct ReadPlanBuilder

pub(crate) struct ReadPlanBuilder {
    batch_size: usize,
    selection: Option<RowSelection>,
}

A builder for ReadPlan

Fields

batch_size: usize

selection: Option<RowSelection>

Current to apply, includes all filters

Implementations

impl ReadPlanBuilder

pub(crate) fn new(batch_size: usize) -> Self

Create a ReadPlanBuilder with the given batch size

pub(crate) fn with_selection(self, selection: Option<RowSelection>) -> Self

Set the current selection to the given value

pub(crate) fn selection(&self) -> Option<&RowSelection>

Returns the current selection, if any

pub(crate) fn limited(self, row_count: usize) -> LimitedReadPlanBuilder

Specifies the number of rows in the row group, before filtering is applied.

Returns a LimitedReadPlanBuilder that can apply offset and limit.

Call LimitedReadPlanBuilder::build_limited to apply the limits to this selection.

pub(crate) fn selects_any(&self) -> bool

Returns true if the current plan selects any rows

pub(crate) fn num_rows_selected(&self) -> Option<usize>

Returns the number of rows selected, or None if all rows are selected.

pub(crate) fn with_predicate( self, array_reader: Box<dyn ArrayReader>, predicate: &mut dyn ArrowPredicate, ) -> Result<Self>

Evaluates an ArrowPredicate, updating this plan’s selection

If the current selection is Some, the resulting RowSelection will be the conjunction of the existing selection and the rows selected by predicate.

Note: pre-existing selections may come from evaluating a previous predicate or if the ParquetRecordBatchReader specified an explicit RowSelection in addition to one or more predicates.

pub(crate) fn build(self) -> ReadPlan

Create a final ReadPlan the read plan for the scan

Trait Implementations

impl Clone for ReadPlanBuilder

fn clone(&self) -> ReadPlanBuilder

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.