Struct MemoryKeyValueStore 

pub struct MemoryKeyValueStore { /* private fields */ }

In-memory Key/Value store used by trait-level tests and future non-SQL fixtures.

Implementations

impl MemoryKeyValueStore

pub fn new() -> Self

Trait Implementations

impl Debug for MemoryKeyValueStore

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Default for MemoryKeyValueStore

fn default() -> MemoryKeyValueStore

Returns the “default value” for a type.

impl KeyValueStore for MemoryKeyValueStore

fn visit_value( &self, key: &[u8], control: &StorageReadControl, visit: &mut ValueReadVisitor<'_>, ) -> StorageBackendResult<()>

Visit one borrowed value under the retained read. Providers reserve any temporary encoded payload before fetching it; callbacks must not reenter the store.

fn visit_prefix_after( &self, prefix: &[u8], after: Option<&[u8]>, limit: usize, control: &StorageReadControl, visit: &mut KeyValueReadVisitor<'_>, ) -> StorageBackendResult<()>

Visit at most limit entries in key order, strictly after after when supplied. Encoded values remain borrowed from their provider owner and callbacks must not reenter the store.

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

fn contains_key(&self, key: &[u8]) -> StorageBackendResult<bool>

fn put(&self, key: &[u8], value: &[u8]) -> StorageBackendResult<()>

fn delete(&self, key: &[u8]) -> StorageBackendResult<()>

fn scan_prefix( &self, prefix: &[u8], ) -> StorageBackendResult<Vec<(Vec<u8>, Vec<u8>)>>

fn scan_prefix_after( &self, prefix: &[u8], after: Option<&[u8]>, limit: usize, ) -> StorageBackendResult<Vec<(Vec<u8>, Vec<u8>)>>

Return at most limit key/value pairs in key order, strictly after after when supplied. This is the bounded value cursor used by large format migrations and other paged consumers.

fn scan_prefix_keys_after( &self, prefix: &[u8], after: Option<&[u8]>, limit: usize, ) -> StorageBackendResult<Vec<Vec<u8>>>

Return at most limit keys in key order, strictly after after when it is present. Backends should override this method with a key-only, bounded range scan so cursor consumers neither materialize the entire prefix nor read values they do not need on every page.

fn first_prefix_after( &self, prefix: &[u8], after: Option<&[u8]>, ) -> StorageBackendResult<Option<(Vec<u8>, Vec<u8>)>>

fn delete_prefix(&self, prefix: &[u8]) -> StorageBackendResult<usize>

fn batch(&self) -> Box<dyn KeyValueBatch + '_>

fn begin_transaction(&self) -> StorageBackendResult<()>

fn begin_read_transaction(&self) -> StorageBackendResult<()>

fn in_transaction(&self) -> bool

fn transaction_has_written(&self) -> StorageBackendResult<bool>

fn change_version(&self) -> StorageBackendResult<Option<u64>>

fn commit_transaction(&self) -> StorageBackendResult<()>

fn rollback_transaction(&self) -> StorageBackendResult<()>

fn savepoint(&self, name: &str) -> StorageBackendResult<()>

fn release_savepoint(&self, name: &str) -> StorageBackendResult<()>

fn rollback_to_savepoint(&self, name: &str) -> StorageBackendResult<()>

fn storage_identity( &self, ) -> StorageBackendResult<Option<PersistentStorageIdentity>>

fn open_session(&self) -> StorageBackendResult<Arc<dyn KeyValueStore>>

Open an independent transaction session over the same logical store. The default keeps simple test/custom stores source-compatible while making the missing MVCC capability explicit when a persistent engine needs a committed reader alongside a pinned statement snapshot.

fn contains_prefix_budgeted( &self, prefix: &[u8], control: &StorageReadControl, ) -> StorageBackendResult<bool>

Test prefix existence under the read allowance. Providers that materialize values should implement a key-only probe.

fn begin_upgradeable_transaction(&self) -> StorageBackendResult<()>

fn change_version_monitor_is_nonblocking(&self) -> StorageBackendResult<bool>

fn pin_transaction_snapshot(&self) -> StorageBackendResult<()>