Struct MemTable 

pub struct MemTable { /* private fields */ }

A basic mem-table based on crossbeam-skiplist.

An initial implementation of memtable is part of week 1, day 1. It will be incrementally implemented in other chapters of week 1 and week 2.

Implementations

impl MemTable

pub fn create(id: usize) -> Self

Create a new mem-table.

pub fn create_with_wal(id: usize, path: impl AsRef<Path>) -> Result<Self>

Create a new mem-table with WAL

pub fn recover_from_wal(id: usize, path: impl AsRef<Path>) -> Result<Self>

Create a memtable from WAL

pub fn for_testing_put_slice(&self, key: &[u8], value: &[u8]) -> Result<()>

pub fn for_testing_get_slice(&self, key: &[u8]) -> Option<Bytes>

pub fn for_testing_scan_slice( &self, lower: Bound<&[u8]>, upper: Bound<&[u8]>, ) -> MemTableIterator

pub fn get(&self, key: &[u8]) -> Option<Bytes>

Get a value by key.

pub fn put(&self, key: &[u8], value: &[u8]) -> Result<()>

Put a key-value pair into the mem-table.

In week 1, day 1, simply put the key-value pair into the skipmap. In week 2, day 6, also flush the data to WAL.

pub fn sync_wal(&self) -> Result<()>

pub fn scan(&self, lower: Bound<&[u8]>, upper: Bound<&[u8]>) -> MemTableIterator

Get an iterator over a range of keys.

pub fn flush(&self, builder: &mut SsTableBuilder) -> Result<()>

Flush the mem-table to SSTable. Implement in week 1 day 6.

pub fn id(&self) -> usize

pub fn approximate_size(&self) -> usize

pub fn is_empty(&self) -> bool

Only use this function when closing the database