Struct FramedRecords 

pub struct FramedRecords { /* private fields */ }

Records read through a spec, by walking them.

Implementations

impl FramedRecords

pub fn open( spec: &Spec, bytes: Arc<Bytes>, header: &HeaderValues, data: Range<usize>, named: &str, path: Option<&Path>, ) -> Result<(Self, Vec<String>), String>

Read spec’s records from bytes[data], with header read already.

pub fn rows(&self) -> usize

pub fn schema(&self) -> SchemaRef

pub fn sources(&self) -> &[Arc<Bytes>]

impl FramedRecords

pub fn lazy(self: &Arc<Self>) -> LazyFrame

The frame: decoded over a row index, only what a query reaches.

pub fn window(&self, start: usize, len: usize) -> PolarsResult<LazyFrame>

Rows [start, start + len) as a frame of their own, read from the nearest checkpoint before them.

pub fn collect(&self, rows: usize) -> PolarsResult<DataFrame>

The first rows rows of every column, decoded now.

Trait Implementations

impl Debug for FramedRecords

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

Formats the value using the given formatter.

impl RowSource for FramedRecords

fn height(&self) -> usize

Rows on hand, at most MAX_ROWS.

fn schema(&self) -> SchemaRef

fn decode(&self, column: usize, index: &IdxCa) -> PolarsResult<Column>

The schema’s columnth column for the rows index names, in that order. The index comes from the plan’s row index, so it has no nulls and every row is under Self::height; a source still refuses one that is not, rather than read past its bytes.

impl SpecRecords for FramedRecords

fn rows(&self) -> usize

fn schema(&self) -> SchemaRef

fn into_lazy(self: Arc<Self>) -> PolarsResult<LazyFrame>

The frame: a scan that decodes only what a query asks for.

fn collect(&self, rows: usize) -> PolarsResult<DataFrame>

The first rows rows, decoded now.

fn sources(&self) -> &[Arc<Bytes>]

The bytes the rows are read from, for a reader of the raw bytes.

impl Windowed for FramedRecords

fn window(&self, start: usize, len: usize) -> PolarsResult<LazyFrame>

The rows as a frame, read when it is collected.