Struct MemoryDatabase

pub struct MemoryDatabase { /* private fields */ }

A key-value database fulfilling the KeyValueDB trait, living in memory. This is generally intended for tests and is not particularly optimized.

Trait Implementations

impl Default for InMemory

fn default() -> InMemory

Returns the “default value” for a type.

impl KeyValueDB for InMemory

fn get(&self, col: u32, key: &[u8]) -> Result<Option<Vec<u8>>, Error>

Get a value by key.

fn get_by_prefix( &self, col: u32, prefix: &[u8], ) -> Result<Option<Vec<u8>>, Error>

Get the first value matching the given prefix.

fn write(&self, transaction: DBTransaction) -> Result<(), Error>

Write a transaction of changes to the backing store.

fn iter<'a>( &'a self, col: u32, ) -> Box<dyn Iterator<Item = Result<(SmallVec<[u8; 32]>, Vec<u8>), Error>> + 'a>

Iterate over the data for a given column.

fn iter_with_prefix<'a>( &'a self, col: u32, prefix: &'a [u8], ) -> Box<dyn Iterator<Item = Result<(SmallVec<[u8; 32]>, Vec<u8>), Error>> + 'a>

Iterate over the data for a given column, returning all key/value pairs where the key starts with the given prefix.

fn transaction(&self) -> DBTransaction

Helper to create a new transaction.

fn io_stats(&self, _kind: Kind) -> IoStats

Query statistics.

fn has_key(&self, col: u32, key: &[u8]) -> Result<bool, Error>

Check for the existence of a value by key.

fn has_prefix(&self, col: u32, prefix: &[u8]) -> Result<bool, Error>

Check for the existence of a value by prefix.