Struct ShardCodec 

pub struct ShardCodec { /* private fields */ }

Packs a physical shard number into the high bits of a u64 id, so any id (primary key or a shard-encoded foreign key) self-describes its shard.

With shard_bits = 12, ids carry a 12-bit shard (up to 4096 shards) and a 52-bit per-shard sequence — ample for app-generated ids. Auto-increment is not used for sharded entities (it can’t carry the shard); the app composes the id with compose.

Implementations

impl ShardCodec

pub const DEFAULT: ShardCodec

A sensible default: 12 shard bits (up to 4096 shards) + 52 sequence bits. Surfaces that don’t need a custom layout can share this so their id schemes agree (and stay portable between a single-DB and a fleet).

pub const fn new(shard_bits: u32) -> Self

pub const fn seq_bits(&self) -> u32

Bits available for the per-shard sequence.

pub const fn shard_of(&self, id: u64) -> u32

The shard number encoded in id.

pub const fn local_of(&self, id: u64) -> u64

The per-shard local part of id.

pub const fn compose(&self, shard: u32, local: u64) -> u64

Compose a full id from a shard number and a per-shard local sequence.

Trait Implementations

impl Clone for ShardCodec

fn clone(&self) -> Self

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Copy for ShardCodec

impl Debug for ShardCodec

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

Formats the value using the given formatter.

impl Eq for ShardCodec

impl PartialEq for ShardCodec

fn eq(&self, other: &Self) -> bool

Equality operator ==.

fn ne(&self, other: &Rhs) -> bool

Inequality operator !=.

impl ShardLocator for ShardCodec

fn locate(&self, key: u64) -> ShardId

impl StructuralPartialEq for ShardCodec