Struct sanakirja::Db

pub struct Db<K: Representable, V: Representable>(_, _);

A database is a skip list of (page offset, key, value).

Trait Implementations

impl<K: Clone + Representable, V: Clone + Representable> Clone for Db<K, V>

fn clone(&self) -> Db<K, V>

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl<K: Debug + Representable, V: Debug + Representable> Debug for Db<K, V>

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

Formats the value using the given formatter.

impl<K: Representable, V: Representable> Representable for Db<K, V>

fn alignment() -> Alignment

Alignment of this type. Allowed values are 1, 2, 4 and 8.

fn onpage_size(&self) -> u16

How much space this value occupies on the page (not counting alignment padding).

unsafe fn skip(p: *mut u8) -> *mut u8

First pointer strictly after this value’s pointer. The default implementation is basically p.offset(self.onpage_size() as isize), but their might be more efficient implementations in some cases.

unsafe fn write_value(&self, p: *mut u8)

Write this value to a u8 pointer, guaranteed to be a multiple of self.alignment().

unsafe fn read_value(p: *const u8) -> Self

Read value from an onpage pointer, guaranteed to be a multiple of self.alignment().

unsafe fn cmp_value<T: LoadPage>(&self, _: &T, x: Db<K, V>) -> Ordering

Compare a value with an onpage value. The current transaction is sometimes helpful, for instance when the page only stores a pointer to another page.

type PageOffsets = Once<u64>

An iterator over the offsets to pages contained in this value. Only values from this crate can generate non-empty iterators, but combined values (like tuples) must chain the iterators returned by method page_offsets.

fn page_offsets(&self) -> Self::PageOffsets

If this value is an offset to another page at offset offset, return Some(offset). Return None else.

fn drop_value<T, R: Rng>(
    &self,
    txn: &mut MutTxn<'_, T>,
    rng: &mut R
) -> Result<(), Error>

How to free the pages used by this value. The default implementation doesn’t do anything, which is fine for types stored directly on B tree pages.

impl<K: Copy + Representable, V: Copy + Representable> Copy for Db<K, V>