As posted in another thread, I am struggeling with database deadlocks, but since this is a different aspect, I have opened a new thread instead:
The issue that I am trying to resolve is as follows: I have an application that uses multiple threads to insert and update data using NHibernate and SQL Server CE. I am getting deadlock issues, because: - thread #1 creates new entries for table ORDER and its children ORDERITEM - thread #2 updates ORDERITEM status and sometimes ORDER status (when all are finished) Apparently, NHibernate generates the following SQL sequence - thread #1: insert into ORDER, then insert into ORDERITEM - thread #2: update ORDERITEM, then update ORDER This is causing deadlocks with thread #1 holding a lock on ORDER waiting for a lock on ORDERITEM and thread #2 the other way round. Unfortunately, SQL Server CE has no way of preventing index PAGE locks, so the threads will conflict, even if they do not access the same rows. I am clear why NHibernate is doing the inserts the way it does - due to the PK/FK constraints, ORDER needs to be inserted first. Why does NHibernate submit the updates ORDERITEM, then ORDER? What influcences that decision and do I have a way to make NHibernate submit the updates ORDER then ORDERITEM? The code in thread #2 loads ORDERITEM and ORDER, does the changes in memory and commits the session. I does not do any explicit session.Update() or .SaveOrUpdate() and the entire configuration is done using fluent automapping with DefaultCascade.SaveUpdate. Thanks for any help. J.- -- You received this message because you are subscribed to the Google Groups "nhusers" group. To view this discussion on the web visit https://groups.google.com/d/msg/nhusers/-/DGBhHta79cMJ. To post to this group, send email to [email protected]. To unsubscribe from this group, send email to [email protected]. For more options, visit this group at http://groups.google.com/group/nhusers?hl=en.
