Struct TxGuard 

pub struct TxGuard<'a> { /* private fields */ }

Guard returned by DB.begin_tx()

Statically guards against outliving db and prevents from making mutable actions.

Implements Deref to Tx

Methods from Deref<Target = Tx>

pub fn writable(&self) -> bool

Returns whether the transaction can perform write operations.

pub fn cursor(&self) -> Cursor<'_, RwLockWriteGuard<'_, Bucket>>

Creates a cursor associated with the root bucket. All items in the cursor will return a nil value because all items in root bucket are also buckets. The cursor is only valid as long as the transaction is open. Do not use a cursor after the transaction is closed.

pub fn stats(&self) -> TxStats

pub fn bucket( &self, key: &[u8], ) -> Result<MappedRwLockReadGuard<'_, Bucket>, Error>

Bucket retrieves a bucket by name. Returns None if the bucket does not exist. The bucket instance is only valid for the lifetime of the transaction.

pub fn buckets(&self) -> Vec<Vec<u8>>

returns bucket keys for db

pub fn for_each<'a, E: Into<Error>>( &self, handler: Box<dyn FnMut(&[u8], Option<&Bucket>) -> Result<(), E> + 'a>, ) -> Result<(), Error>

Executes a function for each bucket in the root. If the provided function returns an error then the iteration is stopped and the error is returned to the caller.

first argument of function is bucket’s key, second is bucket itself

pub fn write_to<W: Write>(&self, w: W) -> Result<i64, Error>

Writes the entire database to a writer. If err == nil then exactly tx.Size() bytes will be written into the writer.

pub fn copy_to(&self, path: &str, mode: OpenOptions) -> Result<(), Error>

Copies the entire database to file at the given path. A reader transaction is maintained during the copy so it is safe to continue using the database while a copy is in progress.

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

Closes the transaction and ignores all previous updates. Read-only transactions must be rolled back and not committed.

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

Sync version of check()

In case of checking thread panic will also return Error

pub fn check(&self) -> Receiver<String>

pub fn freed(&self) -> Result<HashMap<u64, bool>, Error>

pub fn page_info(&self, id: usize) -> Result<Option<PageInfo>, Error>

Returns page information for a given page number. This is only safe for concurrent use when used by a writable transaction.

Trait Implementations

impl<'a> Deref for TxGuard<'a>

type Target = Tx

The resulting type after dereferencing.

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

Dereferences the value.