Struct VersionInfo 

pub struct VersionInfo {
    pub created_epoch: EpochId,
    pub deleted_epoch: Option<EpochId>,
    pub created_by: TransactionId,
    pub deleted_by: Option<TransactionId>,
}

Tracks when a version was created and deleted for visibility checks.

Fields

created_epoch: EpochId

The epoch this version was created in.

deleted_epoch: Option<EpochId>

The epoch this version was deleted in (if any).

created_by: TransactionId

The transaction that created this version.

deleted_by: Option<TransactionId>

The transaction that deleted this version (if any). Used for rollback: only the deleting transaction’s rollback can undelete.

Implementations

impl VersionInfo

pub fn new(created_epoch: EpochId, created_by: TransactionId) -> Self

Creates a new version info.

pub fn mark_deleted(&mut self, epoch: EpochId, deleted_by: TransactionId)

Marks this version as deleted by a specific transaction.

pub fn unmark_deleted_by(&mut self, transaction_id: TransactionId) -> bool

Unmarks deletion if deleted by the given transaction. Returns true if undeleted.

Used during rollback to restore versions deleted within the rolled-back transaction.

pub fn is_visible_at(&self, epoch: EpochId) -> bool

Checks if this version is visible at the given epoch.

pub fn is_visible_to( &self, viewing_epoch: EpochId, viewing_tx: TransactionId, ) -> bool

Checks if this version is visible to a specific transaction.

A version is visible to a transaction if:

1. It was created by the same transaction and not deleted by self, OR
2. It was created in an epoch before the transaction’s start epoch and not deleted before that epoch, and not deleted by this transaction

Trait Implementations

impl Clone for VersionInfo

fn clone(&self) -> VersionInfo

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for VersionInfo

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

Formats the value using the given formatter.

impl Copy for VersionInfo