Method rollbackTransaction

src/Interpreters/TransactionLog.cpp:537–587

}

void TransactionLog::rollbackTransaction(const MergeTreeTransactionPtr & txn) noexcept
{
    LockMemoryExceptionInThread memory_tracker_lock(VariableContext::Global);
    LOG_TRACE(log, "Rolling back transaction {}{}", txn->tid,
              std::uncaught_exceptions() ? fmt::format(" due to uncaught exception (code: {})", getCurrentExceptionCode()) : "");

    if (!txn->rollback())
    {
        /// Transaction was cancelled or committed concurrently
        chassert(txn->csn != Tx::UnknownCSN);
        return;
    }

    {
        auto requests = txn->getRequestsOnRollback();
        if (!requests.empty())
        {
            Coordination::Responses responses;
            auto code = getZooKeeper()->tryMulti(requests, responses);
            if (code == Coordination::Error::ZOK)
            {
                LOG_INFO(log, "Processed requests on rollback {}", requests.size());
            }
            else
            {
                zkutil::KeeperMultiException exception(code, requests, responses);
                if (Coordination::isHardwareError(code))
                    LOG_WARNING(
                        log, "Failed to process requests on rollback {} because of {}", requests.size(), Coordination::toString(code));
                else
                    LOG_WARNING(
                        log,
                        "Failed to process requests on rollback {} because of {} on path {}",
                        requests.size(),
                        Coordination::toString(code),
                        exception.getPathForFirstFailedOp());
            }
        }
    }

    {
        std::lock_guard lock{running_list_mutex};
        bool removed = running_list.erase(txn->tid.getHash());
        if (!removed)
            abort();
        snapshots_in_use.erase(txn->snapshot_in_use_it);
    }

    tryWriteEventToSystemLog(log, global_context, TransactionsInfoLogElement::ROLLBACK, txn->tid);
    txn->afterFinalize();
}

MergeTreeTransactionPtr TransactionLog::tryGetRunningTransaction(const TIDHash & tid)
{