Struct ReadPlanBuilder

pub struct ReadPlanBuilder { /* private fields */ }

A builder for ReadPlan

Implementations

impl ReadPlanBuilder

pub fn new(batch_size: usize) -> Self

Create a ReadPlanBuilder with the given batch size

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

Set the current selection to the given value

pub fn with_row_selection_policy(self, policy: RowSelectionPolicy) -> Self

Configure the policy to use when materialising the RowSelection

Defaults to RowSelectionPolicy::Auto

pub fn row_selection_policy(&self) -> &RowSelectionPolicy

Returns the current row selection policy

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

Returns the current selection, if any

pub fn selects_any(&self) -> bool

Returns true if the current plan selects any rows

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

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

pub 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 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.

impl Debug for ReadPlanBuilder

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

Formats the value using the given formatter.