Struct ReadStatReader 

pub struct ReadStatReader {
    source: Source,
    metadata: Mutex<Option<ReadStatMetadata>>,
    offset: u32,
    limit: Option<u32>,
    columns: Option<Vec<String>>,
    chunk_rows: u32,
    progress: Option<Arc<dyn ProgressCallback>>,
}

High-level, reusable SAS reader.

Configure row and column selection once, then use read, chunks, or visit. visit holds only the current chunk and is therefore the bounded-memory option.

Fields

source: Source

metadata: Mutex<Option<ReadStatMetadata>>

offset: u32

limit: Option<u32>

columns: Option<Vec<String>>

chunk_rows: u32

progress: Option<Arc<dyn ProgressCallback>>

Implementations

impl ReadStatReader

pub fn from_path(path: impl AsRef<Path>) -> Result<Self, ReadStatError>

Creates a reader for a filesystem path.

pub fn from_bytes(bytes: impl Into<Arc<[u8]>>) -> Self

Creates a reader owning an in-memory SAS file.

pub fn from_mmap(path: impl Into<PathBuf>) -> Result<Self, ReadStatError>

Creates a reader which memory maps path for each parse.

fn new(source: Source) -> Self

pub fn rows(self, offset: u32, limit: Option<u32>) -> Self

Selects the half-open row range beginning at offset, optionally limited to limit rows. The range is validated against metadata when reading.

pub fn columns( self, columns: impl IntoIterator<Item = impl Into<String>>, ) -> Self

Selects columns by name, preserving dataset order.

An empty selection deliberately produces a zero-column batch with the requested number of rows.

pub fn chunk_rows(self, rows: u32) -> Self

Sets rows per yielded chunk. Zero is rejected when reading.

pub fn progress(self, callback: Arc<dyn ProgressCallback>) -> Self

Attaches a progress callback.

pub fn metadata(&self) -> Result<ReadStatMetadata, ReadStatError>

Reads and caches metadata transactionally.

Reusing the same reader for metadata and data uses one cached metadata snapshot for planning and avoids a second metadata parse. For path-backed sources, callers must still prevent the file from being replaced between metadata and data parsing, or between repeated reads with this reader.

fn plan(&self) -> Result<ReadPlan, ReadStatError>

pub fn visit( &self, visitor: impl FnMut(RecordBatch) -> Result<(), ReadStatError>, ) -> Result<(), ReadStatError>

Visits each batch without collecting previous chunks.

fn visit_with_plan( &self, plan: &ReadPlan, visitor: impl FnMut(RecordBatch) -> Result<(), ReadStatError>, ) -> Result<(), ReadStatError>

pub fn chunks(&self) -> Result<Vec<RecordBatch>, ReadStatError>

Collects all chunks.

pub fn read(&self) -> Result<RecordBatch, ReadStatError>

Reads the selected rows into one batch.