Struct ArrowFileReader

pub struct ArrowFileReader<R: FileRead> { /* private fields */ }

ArrowFileReader is a wrapper around a FileRead that impls parquets AsyncFileReader.

Implementations

impl<R: FileRead> ArrowFileReader<R>

pub fn new(meta: FileMetadata, r: R) -> Self

Create a new ArrowFileReader

pub fn with_preload_column_index(self, preload: bool) -> Self

Enable or disable preloading of the column index

pub fn with_preload_offset_index(self, preload: bool) -> Self

Enable or disable preloading of the offset index

pub fn with_metadata_size_hint(self, hint: usize) -> Self

Provide a hint as to the number of bytes to prefetch for parsing the Parquet metadata

This hint can help reduce the number of fetch requests. For more details see the ParquetMetaDataReader documentation.

Trait Implementations

impl<R: FileRead> AsyncFileReader for ArrowFileReader<R>

fn get_bytes(&mut self, range: Range<usize>) -> BoxFuture<'_, Result<Bytes>>

Retrieve the bytes in range

fn get_metadata(&mut self) -> BoxFuture<'_, Result<Arc<ParquetMetaData>>>

Provides asynchronous access to the [ParquetMetaData] of a parquet file, allowing fine-grained control over how metadata is sourced, in particular allowing for caching, pre-fetching, catalog metadata, etc…

fn get_byte_ranges( &mut self, ranges: Vec<Range<usize>>, ) -> Pin<Box<dyn Future<Output = Result<Vec<Bytes>, ParquetError>> + Send + '_>>

Retrieve multiple byte ranges. The default implementation will call get_bytes sequentially