Struct tikv::storage::txn::commands::check_txn_status::CheckTxnStatus

pub struct CheckTxnStatus {
    pub ctx: Context,
    pub primary_key: Key,
    pub lock_ts: TimeStamp,
    pub caller_start_ts: TimeStamp,
    pub current_ts: TimeStamp,
    pub rollback_if_not_exist: bool,
    pub force_sync_commit: bool,
    pub resolving_pessimistic_lock: bool,
}

Check the status of a transaction. This is usually invoked by a transaction that meets another transaction’s lock. If the primary lock is expired, it will rollback the primary lock. If the primary lock exists but is not expired, it may update the transaction’s min_commit_ts. Returns a TxnStatus to represent the status.

This is invoked on a transaction’s primary lock. The lock may be generated by either AcquirePessimisticLock or Prewrite.

Fields

ctx: Context

primary_key: Key

The primary key of the transaction.

lock_ts: TimeStamp

The lock’s ts, namely the transaction’s start_ts.

caller_start_ts: TimeStamp

The start_ts of the transaction that invokes this command.

current_ts: TimeStamp

The approximate current_ts when the command is invoked.

rollback_if_not_exist: bool

Specifies the behavior when neither commit/rollback record nor lock is found. If true, rollbacks that transaction; otherwise returns an error.

force_sync_commit: bool

resolving_pessimistic_lock: bool

Implementations

impl CheckTxnStatus

pub fn new(
    primary_key: Key,
    lock_ts: TimeStamp,
    caller_start_ts: TimeStamp,
    current_ts: TimeStamp,
    rollback_if_not_exist: bool,
    force_sync_commit: bool,
    resolving_pessimistic_lock: bool,
    ctx: Context
) -> TypedCommand<TxnStatus>

Return a TypedCommand that encapsulates the result of executing this command.

Trait Implementations

impl CommandExt for CheckTxnStatus

fn get_ctx(&self) -> &Context

fn get_ctx_mut(&mut self) -> &mut Context

fn tag(&self) -> CommandKind

fn incr_cmd_metric(&self)

fn ts(&self) -> TimeStamp

fn write_bytes(&self) -> usize

fn gen_lock(&self) -> Lock

fn readonly(&self) -> bool

fn is_sys_cmd(&self) -> bool

fn can_be_pipelined(&self) -> bool

impl Debug for CheckTxnStatus

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

Formats the value using the given formatter.

impl Display for CheckTxnStatus

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

Formats the value using the given formatter.

impl<S: Snapshot, L: LockManager> WriteCommand<S, L> for CheckTxnStatus

fn process_write(
    self,
    snapshot: S,
    context: WriteContext<'_, L>
) -> Result<WriteResult>

checks whether a transaction has expired its primary lock’s TTL, rollback the transaction if expired, or update the transaction’s min_commit_ts according to the metadata in the primary lock. When transaction T1 meets T2’s lock, it may invoke this on T2’s primary key. In this situation, self.start_ts is T2’s start_ts, caller_start_ts is T1’s start_ts, and the current_ts is literally the timestamp when this function is invoked; it may not be accurate.