Struct DeltaScanExecutionOptions 

pub struct DeltaScanExecutionOptions { /* private fields */ }

Bounded execution settings for one Delta scan.

Implementations

impl DeltaScanExecutionOptions

pub const fn new() -> Self

Returns the baseline execution settings.

pub const fn parquet_backend(&self) -> ParquetReaderBackend

Returns the selected Parquet reader backend.

pub const fn max_concurrent_file_reads_per_scan(&self) -> Option<usize>

Returns the optional scan-wide file-read limit.

pub const fn max_concurrent_file_reads_per_partition(&self) -> usize

Returns the per-partition file-read limit.

pub const fn output_buffer_batches_per_partition(&self) -> usize

Returns the number of output batches buffered per partition.

pub const fn prefetch_files_per_partition(&self) -> usize

Returns the number of future direct Parquet files prepared per partition.

pub const fn parquet_metadata_size_hint_bytes(&self) -> Option<usize>

Returns the direct Parquet reader’s metadata size hint in bytes.

pub const fn parquet_full_file_read_threshold_bytes(&self) -> Option<usize>

Returns the direct Parquet reader’s full-file read threshold in bytes.

pub const fn experimental_intra_page_reads(&self) -> bool

Whether experimental partial-page reads are enabled for the direct backend.

pub const fn with_experimental_intra_page_reads(self, enabled: bool) -> Self

Enables experimental partial reads of supported flat Parquet pages.

Enabled by default. The direct reader uses predicate-derived row numbers to read selected values from PLAIN numeric pages that are uncompressed or held in Zstd raw blocks without checksums. Supports nullable and required INT32, INT64, FLOAT, DOUBLE and FIXED_LEN_BYTE_ARRAY physical columns, including existing decimal conversions. Fixed-length widths come from the Parquet schema. This adds no new Delta type mappings, such as fixed-size binary to Delta binary. UTF-8 and binary columns also support uncompressed DELTA_LENGTH_BYTE_ARRAY pages. All supported pages require V1 layout, offset indexes and no page checksum. Variable-length discovery must fit a modeled fallback budget and shared memory limits; fallback reuses downloaded prefixes. Unsupported layouts and bounded-work limits use ordinary reads. Explicit range-read policies other than Automatic disable this optimization. The Delta Kernel backend ignores this direct-reader option.

Recent query traffic supplies latency and throughput estimates. Partial reads must beat the ordinary plan by more than ten percent, including probes and dependent request rounds. Missing evidence, dense selections, an unmeasured small-request cost, or insufficient shared request capacity retain ordinary reads. Automatic table warmup supplies the full profile for supported S3 stores. If that warmup did not finish, an eligible filtered scan retries it once while building its plan. Passing false restores ordinary reads and skips automatic table warmup when supplied to the table builder. It also skips pending recovery for this scan. Explicit warmup settings remain in effect during table loading.

pub const fn with_parquet_backend( self, parquet_backend: ParquetReaderBackend, ) -> Self

Selects a Parquet reader backend.

pub fn with_max_concurrent_file_reads_per_scan( self, max_concurrent_file_reads: Option<usize>, ) -> Result<Self, DeltaReaderError>

Sets or clears the scan-wide file-read limit.

Explicit limits must be in 1..=tokio::sync::Semaphore::MAX_PERMITS. None derives the limit from the partition target and per-partition limit, capped at Tokio’s maximum.

pub fn with_max_concurrent_file_reads_per_partition( self, max_concurrent_file_reads: usize, ) -> Result<Self, DeltaReaderError>

Sets the per-partition file-read limit.

The limit must be in 1..=tokio::sync::Semaphore::MAX_PERMITS.

pub fn with_output_buffer_batches_per_partition( self, output_buffer_batches: usize, ) -> Result<Self, DeltaReaderError>

Sets the number of output batches buffered per partition.

The capacity must be in 1..=tokio::sync::Semaphore::MAX_PERMITS.

pub const fn with_prefetch_files_per_partition( self, prefetch_files: usize, ) -> Self

Sets the number of future direct Parquet files prepared per partition.

pub fn with_parquet_metadata_size_hint_bytes( self, metadata_size_hint_bytes: Option<usize>, ) -> Result<Self, DeltaReaderError>

Sets or clears the direct Parquet reader’s metadata size hint in bytes.

pub fn with_parquet_full_file_read_threshold_bytes( self, full_file_read_threshold_bytes: Option<usize>, ) -> Result<Self, DeltaReaderError>

Sets or clears the direct Parquet reader’s full-file read threshold in bytes.

Trait Implementations

impl Clone for DeltaScanExecutionOptions

fn clone(&self) -> Self

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Copy for DeltaScanExecutionOptions

impl Debug for DeltaScanExecutionOptions

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

Formats the value using the given formatter.

impl Default for DeltaScanExecutionOptions

fn default() -> Self

Returns the “default value” for a type.

impl Eq for DeltaScanExecutionOptions

impl PartialEq for DeltaScanExecutionOptions

fn eq(&self, other: &Self) -> bool

Equality operator ==.

fn ne(&self, other: &Rhs) -> bool

Inequality operator !=.

impl StructuralPartialEq for DeltaScanExecutionOptions