Struct mmtkvdb::EnvRw

pub struct EnvRw { /* private fields */ }

Read-write handle for accessing environment that stores key-value databases

An environment can be opened using EnvBuilder.

EnvRw coerces to EnvRo through Deref coercion, thus all methods of EnvRo are available for EnvRw as well.

Use EnvRo::open_db or EnvRw::create_db to retrieve database handles and EnvRw::txn_rw to start a read-write transaction.

It’s possible to create a read-only handle from a read-write handle by invoking .clone(), which clones the referenced EnvRo through deref coercion (see example for EnvBuilder).

Implementations

impl EnvRw

pub fn nestable_txns(&self) -> bool

Check if transactions are nestable

See TxnRw::nested.

pub unsafe fn create_dbs<'a, K, V, C>(
    &mut self,
    options: impl IntoIterator<IntoIter = impl Iterator<Item = &'a DbOptions<K, V, C, Option<CString>>> + ExactSizeIterator>
) -> Result<Vec<Db<K, V, C>>, Error> where
    K: ?Sized + Storable + 'a,
    V: ?Sized + Storable + 'a,
    C: Constraint, 

Open databases in environment and create if non-existing

SAFETY: If a database exists already, it must have been created with compatible options.

pub unsafe fn create_db<K, V, C>(
    &mut self,
    options: &DbOptions<K, V, C, Option<CString>>
) -> Result<Db<K, V, C>, Error> where
    K: ?Sized + Storable,
    V: ?Sized + Storable,
    C: Constraint, 

Open database in environment and create if non-existing

SAFETY: If a database exists already, it must have been created with compatible options.

pub fn drop_db<K, V, C>(&self, db: Db<K, V, C>) -> Result<(), Error> where
    K: ?Sized + Storable,
    V: ?Sized + Storable,
    C: Constraint, 

Delete database in environment

pub fn txn_rw(&mut self) -> Result<TxnRw<'_>, Error>

Start read-write transaction

Methods from Deref<Target = EnvRo>

pub fn txn_ro(&self) -> Result<TxnRo<'_>, Error>

Start read-only transaction

pub fn max_keysize(&self) -> usize

Get maximum size of keys and duplicate data

pub fn valid_keysize<'kr, K, KRef>(&self, key: KRef) -> bool where
    K: ?Sized + Storable + 'kr,
    KRef: StorableRef<'kr, K>, 

Checks if key or duplicate data has valid size

pub unsafe fn open_dbs<'a, K, V, C>(
    &self,
    options: impl IntoIterator<IntoIter = impl Iterator<Item = &'a DbOptions<K, V, C, Option<CString>>> + ExactSizeIterator>
) -> Result<Vec<Db<K, V, C>>, Error> where
    K: ?Sized + Storable + 'a,
    V: ?Sized + Storable + 'a,
    C: Constraint, 

Open databases in environment

SAFETY: If a database exists already, it must have been created with compatible options.

pub unsafe fn open_db<K, V, C>(
    &self,
    options: &DbOptions<K, V, C, Option<CString>>
) -> Result<Db<K, V, C>, Error> where
    K: ?Sized + Storable,
    V: ?Sized + Storable,
    C: Constraint, 

Open database in environment

SAFETY: If a database exists already, it must have been created with compatible options.

pub fn clear_stale_readers(&self) -> Result<(), Error>

Clear stale readers

Refer to LMDB’s documentation when to clear stale readers

Trait Implementations

impl Debug for EnvRw

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

Formats the value using the given formatter.

impl Deref for EnvRw

type Target = EnvRo

The resulting type after dereferencing.

fn deref(&self) -> &Self::Target

Dereferences the value.

impl Hash for EnvRw

fn hash<__H: Hasher>(&self, state: &mut __H)

Feeds this value into the given Hasher.

fn hash_slice<H>(data: &[Self], state: &mut H) where
    H: Hasher, 

Feeds a slice of this type into the given Hasher.

impl PartialEq<EnvRw> for EnvRw

fn eq(&self, other: &EnvRw) -> bool

This method tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &EnvRw) -> bool

This method tests for !=.

impl Eq for EnvRw

impl StructuralEq for EnvRw

impl StructuralPartialEq for EnvRw