Struct Snapshot 

pub struct Snapshot { /* private fields */ }

A cross-keyspace snapshot

Snapshots keep a consistent view of the database at the time, meaning old data will not be dropped until it is not referenced by any active transaction.

For that reason, you should try to keep transactions short-lived, and make sure they are not held somewhere forever.

Trait Implementations

impl Clone for Snapshot

fn clone(&self) -> Snapshot

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Readable for Snapshot

fn get<K: AsRef<[u8]>>( &self, keyspace: impl AsRef<Keyspace>, key: K, ) -> Result<Option<UserValue>>

Retrieves an item from the snapshot.

fn contains_key<K: AsRef<[u8]>>( &self, keyspace: impl AsRef<Keyspace>, key: K, ) -> Result<bool>

Returns true if the snapshot contains the specified key.

fn first_key_value(&self, keyspace: impl AsRef<Keyspace>) -> Option<Guard>

Returns the first key-value pair in the snapshot. The key in this pair is the minimum key in the snapshot.

fn last_key_value(&self, keyspace: impl AsRef<Keyspace>) -> Option<Guard>

Returns the last key-value pair in the snapshot. The key in this pair is the maximum key in the snapshot.

fn size_of<K: AsRef<[u8]>>( &self, keyspace: impl AsRef<Keyspace>, key: K, ) -> Result<Option<u32>>

Retrieves the size of an item from the snapshot.

fn iter(&self, keyspace: impl AsRef<Keyspace>) -> Iter

Iterates over the snapshot.

fn range<K: AsRef<[u8]>, R: RangeBounds<K>>( &self, keyspace: impl AsRef<Keyspace>, range: R, ) -> Iter

Iterates over a range of the snapshot.

fn prefix<K: AsRef<[u8]>>( &self, keyspace: impl AsRef<Keyspace>, prefix: K, ) -> Iter

Iterates over a prefixed set of the snapshot.

fn is_empty(&self, keyspace: impl AsRef<Keyspace>) -> Result<bool>

Returns true if the parkeyspacetition is empty.

fn len(&self, keyspace: impl AsRef<Keyspace>) -> Result<usize>

Scans the entire keyspace, returning the number of items.