Struct RwCursor

pub struct RwCursor<'txn> { /* private fields */ }

A read-write cursor for navigating items within a database.

Implementations

impl<'txn> RwCursor<'txn>

pub fn put<K, D>(&mut self, key: &K, data: &D, flags: WriteFlags) -> Result<()>

where K: AsRef<[u8]>, D: AsRef<[u8]>,

Puts a key/data pair into the database. The cursor will be positioned at the new data item, or on failure usually near it.

pub fn del(&mut self, flags: WriteFlags) -> Result<()>

Deletes the current key/data pair.

Flags

WriteFlags::NO_DUP_DATA may be used to delete all data items for the current key, if the database was opened with DatabaseFlags::DUP_SORT.

Trait Implementations

impl<'txn> Cursor<'txn> for RwCursor<'txn>

fn cursor(&self) -> *mut MDB_cursor

Returns a raw pointer to the underlying LMDB cursor.

fn get( &self, key: Option<&[u8]>, data: Option<&[u8]>, op: c_uint, ) -> Result<(Option<&'txn [u8]>, &'txn [u8])>

Retrieves a key/data pair from the cursor. Depending on the cursor op, the current key may be returned.

fn iter(&mut self) -> Iter<'txn>

Iterate over database items. The iterator will begin with item next after the cursor, and continue until the end of the database. For new cursors, the iterator will begin with the first item in the database.

fn iter_start(&mut self) -> Iter<'txn>

Iterate over database items starting from the beginning of the database.

fn iter_from<K>(&mut self, key: K) -> Iter<'txn>

where K: AsRef<[u8]>,

Iterate over database items starting from the given key.

fn iter_dup(&mut self) -> IterDup<'txn>

Iterate over duplicate database items. The iterator will begin with the item next after the cursor, and continue until the end of the database. Each item will be returned as an iterator of its duplicates.

fn iter_dup_start(&mut self) -> IterDup<'txn>

Iterate over duplicate database items starting from the beginning of the database. Each item will be returned as an iterator of its duplicates.

fn iter_dup_from<K>(&mut self, key: K) -> IterDup<'txn>

where K: AsRef<[u8]>,

Iterate over duplicate items in the database starting from the given key. Each item will be returned as an iterator of its duplicates.

fn iter_dup_of<K>(&mut self, key: K) -> Iter<'txn>

where K: AsRef<[u8]>,

Iterate over the duplicates of the item in the database with the given key.

impl<'txn> Debug for RwCursor<'txn>

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

Formats the value using the given formatter.

impl<'txn> Drop for RwCursor<'txn>

fn drop(&mut self)

Executes the destructor for this type.