On Tue, Jun 16, 2015 at 1:08 PM, Xiaoyulei <xiaoyu...@huawei.com> wrote: > In XidInMVCCSnapshot, it will check xid from tuple if is in snapshot->subxip. > It means tuple store subtransaction?
Tuple stores only the transaction id related to the operation. This can be either main transaction id or sub transaction id. > But in PushTransaction, I see TransactionState.subTransaction will assign > currentSubTransactionId, currentSubTransactionId will reinitialize in > StartTransaction. So I think tuple should not store subtransaction id. > > I am confuse about this. If subtransaction id will reinitialize every start > time. How to judge it is a subtransaction from xid in tuple? StartTransaction is called only once per transaction.Further on for sub transactions it calls only startSubTransaction. Hope this answers your question. Regards, Hari Babu Fujitsu Australia -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
