Trait DupReadCursor 

pub trait DupReadCursor<'txn, T: DupTable>: ReadCursor<'txn, T> {
    // Required methods
    fn first_duplicate(&mut self) -> Option<T::Value>;
    fn last_duplicate(&mut self) -> Option<T::Value>;
    fn next_duplicate(&mut self) -> Option<Row<T>>;
    fn next_no_duplicate(&mut self) -> Option<Row<T>>;
    fn prev_duplicate(&mut self) -> Option<Row<T>>;
    fn prev_no_duplicate(&mut self) -> Option<Row<T>>;
    fn set_subkey(
        &mut self,
        key: &T::Key,
        subkey: &DupSubKey<T>,
    ) -> Option<T::Value>
       where T::Value: DupTableValue;
    fn set_lowerbound_both(
        &mut self,
        key: &T::Key,
        subkey: &DupSubKey<T>,
    ) -> Option<Row<T>>
       where T::Value: DupTableValue;
    fn set_lowerbound_subkey(
        &mut self,
        key: &T::Key,
        subkey: &DupSubKey<T>,
    ) -> Option<T::Value>
       where T::Value: DupTableValue;
    fn count_duplicates(&mut self) -> usize;
    fn into_iter_dup_of(self, key: &T::Key) -> Self::IntoIter;
}

Required Methods

fn first_duplicate(&mut self) -> Option<T::Value>

Positions the cursor at the first duplicate value for the current key.

fn last_duplicate(&mut self) -> Option<T::Value>

Positions the cursor at the last duplicate value for the current key.

fn next_duplicate(&mut self) -> Option<Row<T>>

Positions the cursor at the next duplicate value for the current key. This does not jump keys.

fn next_no_duplicate(&mut self) -> Option<Row<T>>

Positions the cursor at the first duplicate of the next key.

fn prev_duplicate(&mut self) -> Option<Row<T>>

Positions the cursor at the previous duplicate value for the current key.

fn prev_no_duplicate(&mut self) -> Option<Row<T>>

Positions the cursor at the last duplicate of the previous key.

fn set_subkey( &mut self, key: &T::Key, subkey: &DupSubKey<T>, ) -> Option<T::Value>

where T::Value: DupTableValue,

Positions the cursor at the entry with a given key and subkey.

fn set_lowerbound_both( &mut self, key: &T::Key, subkey: &DupSubKey<T>, ) -> Option<Row<T>>

where T::Value: DupTableValue,

Positions the cursor at the first duplicate entry that has a key >= key && subkey >= subkey.

fn set_lowerbound_subkey( &mut self, key: &T::Key, subkey: &DupSubKey<T>, ) -> Option<T::Value>

where T::Value: DupTableValue,

Positions the cursor at the first duplicate entry that has a key == key && subkey >= subkey.

fn count_duplicates(&mut self) -> usize

Counts the number of duplicates (linear operation!).

fn into_iter_dup_of(self, key: &T::Key) -> Self::IntoIter

Iterates over all duplicates of the given key.

Dyn Compatibility

This trait is not dyn compatible.

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

Implementors

impl<'txn, Kind: TransactionKind, T: DupTable> DupReadCursor<'txn, T> for MdbxCursor<'txn, Kind, T>

impl<'txn, T: DupTable> DupReadCursor<'txn, T> for CursorProxy<'txn, T>