Struct Snapshot

pub struct Snapshot<Cod: Codec = ApiV1TxnCodec, PdC: PdClient<Codec = Cod> = PdRpcClient<Cod>> { /* private fields */ }

A read-only transaction which reads at the given timestamp.

It behaves as if the snapshot was taken at the given timestamp, i.e. it can read operations happened before the timestamp, but ignores operations after the timestamp.

See the Transaction docs for more information on the methods.

Implementations

impl<Cod: Codec, PdC: PdClient<Codec = Cod>> Snapshot<Cod, PdC>

pub fn new(transaction: Transaction<Cod, PdC>) -> Self

Constructs a new Snapshot.

impl<Cod: Codec, PdC: PdClient<Codec = Cod>> Snapshot<Cod, PdC>

pub async fn get(&mut self, key: impl Into<Key>) -> Result<Option<Value>>

Get the value associated with the given key.

pub async fn key_exists(&mut self, key: impl Into<Key>) -> Result<bool>

Check whether the key exists.

pub async fn batch_get( &mut self, keys: impl IntoIterator<Item = impl Into<Key>>, ) -> Result<impl Iterator<Item = KvPair>>

Get the values associated with the given keys.

pub async fn scan( &mut self, range: impl Into<BoundRange>, limit: u32, ) -> Result<impl Iterator<Item = KvPair>>

Scan a range, return at most limit key-value pairs that lying in the range.

pub async fn scan_keys( &mut self, range: impl Into<BoundRange>, limit: u32, ) -> Result<impl Iterator<Item = Key>>

Scan a range, return at most limit keys that lying in the range.

pub async fn scan_reverse( &mut self, range: impl Into<BoundRange>, limit: u32, ) -> Result<impl Iterator<Item = KvPair>>

Similar to scan, but in the reverse direction.

pub async fn scan_keys_reverse( &mut self, range: impl Into<BoundRange>, limit: u32, ) -> Result<impl Iterator<Item = Key>>

Similar to scan_keys, but in the reverse direction.