Struct PrunableStatistics 

pub struct PrunableStatistics {
    statistics: Vec<Arc<Statistics>>,
    schema: SchemaRef,
}

Prune a set of containers represented by their statistics.

Each Statistics represents a “container” – some collection of data that has statistics of its columns.

It is up to the caller to decide what each container represents. For example, they can come from a file (e.g. PartitionedFile) or a set of of files (e.g. FileGroup)

Fields

statistics: Vec<Arc<Statistics>>

Statistics for each container. These are taken as a reference since they may be rather large / expensive to clone and we often won’t return all of them as ArrayRefs (we only return the columns the predicate requests).

schema: SchemaRef

The schema of the file these statistics are for.

Implementations

impl PrunableStatistics

pub fn new(statistics: Vec<Arc<Statistics>>, schema: SchemaRef) -> Self

Create a new instance of PrunableStatistics. Each Statistics represents a container (e.g. a file or a partition of files). The schema is the schema of the data in the containers and should apply to all files.

fn get_exact_column_statistics( &self, column: &Column, get_stat: impl Fn(&ColumnStatistics) -> &Precision<ScalarValue>, ) -> Option<ArrayRef>

Trait Implementations

impl Clone for PrunableStatistics

fn clone(&self) -> PrunableStatistics

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl PruningStatistics for PrunableStatistics

fn min_values(&self, column: &Column) -> Option<ArrayRef>

Return the minimum values for the named column, if known.

fn max_values(&self, column: &Column) -> Option<ArrayRef>

Return the maximum values for the named column, if known.

fn num_containers(&self) -> usize

Return the number of containers (e.g. Row Groups) being pruned with these statistics.

fn null_counts(&self, column: &Column) -> Option<ArrayRef>

Return the number of null values for the named column as an UInt64Array

fn row_counts(&self, column: &Column) -> Option<ArrayRef>

Return the number of rows for the named column in each container as an UInt64Array.

fn contained( &self, _column: &Column, _values: &HashSet<ScalarValue>, ) -> Option<BooleanArray>

Returns [BooleanArray] where each row represents information known about specific literal values in a column.