Enum ColumnChunkData 

pub(crate) enum ColumnChunkData {
    Sparse {
        length: usize,
        data: Vec<(usize, Bytes)>,
    },
    Dense {
        offset: usize,
        data: Bytes,
    },
}

An in-memory column chunk. This allows us to hold either dense column chunks or sparse column chunks and easily access them by offset.

Variants

Sparse

Column chunk data representing only a subset of data pages. For example if a row selection (possibly caused by a filter in a query) causes us to read only a subset of the rows in the column.

Fields

length: usize

Length of the full column chunk

data: Vec<(usize, Bytes)>

Subset of data pages included in this sparse chunk.

Each element is a tuple of (page offset within file, page data). Each entry is a complete page and the list is ordered by offset.

Dense

Full column chunk and the offset within the original file

Fields

offset: usize

data: Bytes

Implementations

impl ColumnChunkData

fn get(&self, start: u64) -> Result<Bytes>

Return the data for this column chunk at the given offset

Trait Implementations

impl ChunkReader for ColumnChunkData

type T = Reader<Bytes>

The concrete type of reader returned by this trait

fn get_read(&self, start: u64) -> Result<Self::T>

Get a Read instance starting at the provided file offset

fn get_bytes(&self, start: u64, length: usize) -> Result<Bytes>

Get a range of data in memory as [Bytes]

impl Clone for ColumnChunkData

fn clone(&self) -> ColumnChunkData

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for ColumnChunkData

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

Formats the value using the given formatter.

impl Length for ColumnChunkData

fn len(&self) -> u64

Return the total length of the full column chunk