Trait ReadTransaction 

pub trait ReadTransaction<'db>: Sized {
    type Cursor<'txn, T: Table>: ReadCursor<'txn, T>
       where Self: 'txn;
    type DupCursor<'txn, T: DupTable>: ReadCursor<'txn, T> + DupReadCursor<'txn, T>
       where Self: 'txn;

    // Required methods
    fn get<T: Table>(&self, table: &T, key: &T::Key) -> Option<T::Value>;
    fn cursor<'txn, T: RegularTable>(
        &'txn self,
        table: &T,
    ) -> Self::Cursor<'txn, T>;
    fn dup_cursor<'txn, T: DupTable>(
        &'txn self,
        table: &T,
    ) -> Self::DupCursor<'txn, T>;

    // Provided method
    fn close(self) { ... }
}

Read-transactions can only perform read operations on a database.

Required Associated Types

type Cursor<'txn, T: Table>: ReadCursor<'txn, T> where Self: 'txn

type DupCursor<'txn, T: DupTable>: ReadCursor<'txn, T> + DupReadCursor<'txn, T> where Self: 'txn

Required Methods

fn get<T: Table>(&self, table: &T, key: &T::Key) -> Option<T::Value>

Gets the value at a given key.

fn cursor<'txn, T: RegularTable>(&'txn self, table: &T) -> Self::Cursor<'txn, T>

Creates a cursor for iterating over the table.

fn dup_cursor<'txn, T: DupTable>( &'txn self, table: &T, ) -> Self::DupCursor<'txn, T>

Creates a cursor for iterating over the table with duplicate keys.

Provided Methods

fn close(self)

Close the transaction, releasing any resources it holds.

Dyn Compatibility

This trait is not dyn compatible.

In older versions of Rust, dyn compatibility was called "object safety".

Implementors

impl<'db, 'inner> ReadTransaction<'db> for TransactionProxy<'db, 'inner>

where 'db: 'inner,

type Cursor<'txn, T: Table> = CursorProxy<'txn, T> where 'inner: 'txn

type DupCursor<'txn, T: DupTable> = CursorProxy<'txn, T> where 'inner: 'txn

impl<'db, Kind> ReadTransaction<'db> for MdbxTransaction<'db, Kind>

where Kind: TransactionKind,

type Cursor<'txn, T: Table> = MdbxCursor<'txn, Kind, T> where 'db: 'txn

type DupCursor<'txn, T: DupTable> = MdbxCursor<'txn, Kind, T> where 'db: 'txn

impl<'db> ReadTransaction<'db> for MdbxReadTransaction<'db>

type Cursor<'txn, T: Table> = CursorProxy<'txn, T> where Self: 'txn

type DupCursor<'txn, T: DupTable> = CursorProxy<'txn, T> where Self: 'txn

impl<'db> ReadTransaction<'db> for MdbxWriteTransaction<'db>

type Cursor<'txn, T: Table> = CursorProxy<'txn, T> where Self: 'txn

type DupCursor<'txn, T: DupTable> = CursorProxy<'txn, T> where Self: 'txn