Hi, It sounds like you want something like the TransactionStore utility (org.h2.mvstore.db.TransactionStore), but for serializable transactions: http://h2database.com/html/mvstore.html#transactions
> I would like to get reads of values to either block until the other writing-transactions finish, or fail so I can re-execute at a later time. Yes, that's what it's doing. But not there are some differences between "serializable" (what you want) and "read committed" (what the TransactionStore supports right now) - for details, see http://www.postgresql.org/docs/9.3/static/transaction-iso.html and http://en.wikipedia.org/wiki/Isolation_(database_systems) Please have a look at the docs, and then let's discuss whether you want to extend the current mechanism or write your own. I'm also interested in having serializable transaction isolation for H2 as an option, but would like to keep the current mechanism as the default. Regards, Thomas On Fri, Apr 18, 2014 at 10:39 AM, Kieron Wilkinson < [email protected]> wrote: > Hi, > > I've been looking for an in-memory key-value database. I couldn't find > anything (that was missing deal breaker features), so I spent several days > writing my own one, and then realised how hard it was ;). I did some more > investigation and thankfully found MVStore. > > Anyway, I think it provides pretty much everything I need (which is > fantastic!). One of the things it doesn't do is something similar to > serializable transaction isolation. I would like to get reads of values to > either block until the other writing-transactions finish, or fail so I can > re-execute at a later time. > > So, I was wondering, if I wanted to plug this functionality in, whether > you guys had any hints on the best way to go about that? I was assuming > that since H2 itself supports serializable isolation, that this can be > easily implemented on top? Maybe, if you think it's useful, I can even make > my code generic enough that it is useful for others, as an optional > component for MVStore. > > I also would like to customise the support for 2-phase commit. I would > like to apply my application's optimistic locking checks in the prepare > phase (which I can do externally), but after taking write locks in the > prepare phase to enforce the contract of these checks on commit. Does that > seem possible? > > Anyway, thanks very much for your work. > > Kieron Wilkinson > > -- > You received this message because you are subscribed to the Google Groups > "H2 Database" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected]. > To post to this group, send email to [email protected]. > Visit this group at http://groups.google.com/group/h2-database. > For more options, visit https://groups.google.com/d/optout. > -- You received this message because you are subscribed to the Google Groups "H2 Database" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To post to this group, send email to [email protected]. Visit this group at http://groups.google.com/group/h2-database. For more options, visit https://groups.google.com/d/optout.
