Struct BackwardSstableIterator 

pub struct BackwardSstableIterator {
    block_iter: Option<BlockIterator>,
    cur_idx: usize,
    sst: TableHolder,
    sstable_store: SstableStoreRef,
    stats: StoreLocalStatistic,
    read_block_meta_range: (usize, usize),
}

Iterates backwards on a sstable.

Fields

block_iter: Option<BlockIterator>

The iterator of the current block.

cur_idx: usize

Current block index.

sst: TableHolder

Reference to the sstable

sstable_store: SstableStoreRef

stats: StoreLocalStatistic

read_block_meta_range: (usize, usize)

Implementations

impl BackwardSstableIterator

pub fn new( sstable: TableHolder, sstable_store: SstableStoreRef, sstable_info_ref: &SstableInfo, ) -> Self

async fn seek_idx( &mut self, idx: isize, seek_key: Option<FullKey<&[u8]>>, ) -> HummockResult<()>

Seeks to a block, and then seeks to the key if seek_key is given.

Trait Implementations

impl HummockIterator for BackwardSstableIterator

async fn rewind(&mut self) -> HummockResult<()>

Instead of setting idx to 0th block, a BackwardSstableIterator rewinds to the last block in the sstable.

type Direction = Backward

async fn next(&mut self) -> HummockResult<()>

Moves a valid iterator to the next key.

fn key(&self) -> FullKey<&[u8]>

Retrieves the current key.

fn value(&self) -> HummockValue<&[u8]>

Retrieves the current value, decoded as HummockValue.

fn is_valid(&self) -> bool

Indicates whether the iterator can be used.

async fn seek<'a>(&'a mut self, key: FullKey<&'a [u8]>) -> HummockResult<()>

Resets iterator and seeks to the first position where the key >= provided key, or key <= provided key if this is a backward iterator.

fn collect_local_statistic(&self, stats: &mut StoreLocalStatistic)

take local statistic info from iterator to report metrics.

fn value_meta(&self) -> ValueMeta

Returns value meta.

impl SstableIteratorType for BackwardSstableIterator

fn create( sstable: TableHolder, sstable_store: SstableStoreRef, _: Arc<SstableIteratorReadOptions>, sstable_info_ref: &SstableInfo, ) -> Self