Struct leveldb::database::Database

pub struct Database<K: Key> { /* fields omitted */ }

The main database object.

leveldb databases are based on ordered keys. By default, leveldb orders by the binary value of the key. Additionally, a custom Comparator can be passed when opening the database. This library ships with an Comparator implementation for keys that are Ord.

When re-CString a database, you must use the same key type K and comparator type C.

Multiple Database objects can be kept around, as leveldb synchronises internally.

Methods

impl<K: Key> Database<K>

pub fn open(name: &Path, options: Options) -> Result<Database<K>, Error>

Open a new database

If the database is missing, the behaviour depends on options.create_if_missing. The database will be created using the settings given in options.

pub fn open_with_comparator<C: Comparator<K = K>>(
    name: &Path,
    options: Options,
    comparator: C
) -> Result<Database<K>, Error>

Open a new database with a custom comparator

If the database is missing, the behaviour depends on options.create_if_missing. The database will be created using the settings given in options.

The comparator must implement a total ordering over the keyspace.

For keys that implement Ord, consider the OrdComparator.

Trait Implementations

impl<'a, K: Key + 'a> Iterable<'a, K> for Database<K>

Important traits for Iterator<'a, K>

impl<'a, K: Key> Iterator for Iterator<'a, K> type Item = (K, Vec<u8>);

fn iter(&'a self, options: ReadOptions<'a, K>) -> Iterator<K>

Return an Iterator iterating over (Key,Value) pairs

Important traits for KeyIterator<'a, K>

impl<'a, K: Key> Iterator for KeyIterator<'a, K> type Item = K;

fn keys_iter(&'a self, options: ReadOptions<'a, K>) -> KeyIterator<K>

Returns an Iterator iterating over Keys only.

Important traits for ValueIterator<'a, K>

impl<'a, K: Key> Iterator for ValueIterator<'a, K> type Item = Vec<u8>;

fn value_iter(&'a self, options: ReadOptions<'a, K>) -> ValueIterator<K>

Returns an Iterator iterating over Values only.

impl<K: Key> Snapshots<K> for Database<K>

fn snapshot<'a>(&'a self) -> Snapshot<'a, K>

Creates a snapshot and returns a struct representing it.

impl<K: Key> KV<K> for Database<K>

fn put<BK: Borrow<K>>(
    &self,
    options: WriteOptions,
    key: BK,
    value: &[u8]
) -> Result<(), Error>

put a binary value into the database.

If the key is already present in the database, it will be overwritten.

The passed key will be compared using the comparator.

The database will be synced to disc if options.sync == true. This is NOT the default.

fn delete<BK: Borrow<K>>(
    &self,
    options: WriteOptions,
    key: BK
) -> Result<(), Error>

delete a value from the database.

The passed key will be compared using the comparator.

The database will be synced to disc if options.sync == true. This is NOT the default.

fn get<'a, BK: Borrow<K>>(
    &self,
    options: ReadOptions<'a, K>,
    key: BK
) -> Result<Option<Vec<u8>>, Error>

get a value from the database.

The passed key will be compared using the comparator.

impl<K: Key> Batch<K> for Database<K>

fn write(
    &self,
    options: WriteOptions,
    batch: &Writebatch<K>
) -> Result<(), Error>

Write a batch to the database, ensuring success for all items or an error

impl<'a, K: Key + 'a> Compaction<'a, K> for Database<K>

fn compact(&self, start: &'a K, limit: &'a K)

impl<K: Key> Send for Database<K>

impl<K: Key> Sync for Database<K>