Struct nihdb::Store

pub struct Store { /* fields omitted */ }

Methods

impl Store

fn create(dir: &str) -> Result<(), Error>

Creates a new store in a new directory.

fn open(dir: &str, threshold: usize) -> Result<Store, Error>

Opens the store.

threshold is an upper bound on the size of unflushed data.

fn insert(&mut self, key: &[u8], val: &[u8]) -> Result<bool, Error>

Inserts a key/value pair into the store if the key is not already present. Returns true if an insertion happened.

fn replace(&mut self, key: &[u8], val: &[u8]) -> Result<bool, Error>

Replaces an existing key/value pair in the store. If the key is not present, does nothing and returns false.

fn put(&mut self, key: &[u8], val: &[u8]) -> Result<(), Error>

Puts a key/value pair into the store, replacing the value if the key is already present. Compare to insert or replace.

fn remove(&mut self, key: &[u8]) -> Result<bool, Error>

Removes a key/value pair from the store. Returns true if the key was present.

fn sync(&mut self) -> Result<(), Error>

Ensures that all preceding write operations have been written to disk (if you trust your kernel and your disk).

fn flush(&mut self) -> Result<(), Error>

Flushes any buffered write operations to disk.

fn exists(&mut self, key: &[u8]) -> Result<bool, Error>

Returns true if a key/value pair is present, for the given key.

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

Gets the value for the specified key/value pair, or None if the key does not exist.

fn range_directed<'a>(
    &'a self,
    interval: &Interval<Vec<u8>>,
    direction: Direction
) -> Result<StoreIter<'a>, Error>

Produces a store iterator for iterating the store over the given interval, in the given direction.

fn range<'a>(
    &'a self,
    interval: &Interval<Vec<u8>>
) -> Result<StoreIter<'a>, Error>

Creates a StoreIter for iterating forwards through the interval.

fn range_descending<'a>(
    &'a self,
    interval: &Interval<Vec<u8>>
) -> Result<StoreIter<'a>, Error>

Creates a StoreIter for iterating backwards through the interval.

fn next(
    &self,
    iter: &mut StoreIter
) -> Result<Option<(Vec<u8>, Vec<u8>)>, Error>

Produces the next key/value pair from the StoreIter. Returns None to mark the end of iteration.