To be clear this is the same row I am talking about. So even in that scenario, with this mvcc case fixed, H2 would still block the reader in the second transaction is what I am hearing. Could you plase confim my understanding is correct?
-- Sent from my Palm Pre [email protected] http://hibernate.orgOn May 9, 2010 12:59 PM, Thomas Mueller <[email protected]> wrote: Hi, > Using MVCC, should writers cause readers to block? No. Usually not. However, SELECT ... FOR UPDATE does not do what it "should" do in MVCC mode. This is a known problem, and it's on the roadmap since quite a long time ("MVCC: select for update should only lock the selected rows."). Currently, SELECT ... FOR UPDATE locks the whole table (no matter what) in exclusive mode. That means even queries are blocked. I hope I can change that in the next release, but I'm not sure yet. > Is that expected behavior for H2's MVCC? It's a known issue. Regards, Thomas -- You received this message because you are subscribed to the Google Groups "H2 Database" group. 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/h2-database?hl=en. -- You received this message because you are subscribed to the Google Groups "H2 Database" group. 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/h2-database?hl=en.
