[
Date Prev][
Date Next][
Thread Prev][
Thread Next][
Date Index][
Thread Index]
[
List Home]
Re: [rdf4j-dev] Question about READ_UNCOMMITTED
|
Hi Håvard,
It looks like the test in wrong. I think it was originally written
before isolation levels and should be skipped for READ_UNCOMMITTED as
well.
Can you create a PR for this?
Thanks,
James
On Sat, 2017-07-22 at 16:28 +0200, Håvard Ottestad wrote:
> Hi,
>
> There is a test in RepositoryConnectionTest called testEmptyCommit().
> This test seems to do the following:
>
> - Create two connections
> - Add data to one of the connections
> - Make sure the other connection doesn’t see said data
>
> This test is being run at READ_UNCOMMITTED isolation level. I’m
> wondering then if the definition of READ_UNCOMMITTED is correct.
>
> The current definition is:
> /**
> * Read Uncommitted: transactions can be rolled back, but not
> necessarily isolated: concurrent
> * transactions might see each other's uncommitted data (so-called
> 'dirty reads')
> */
>
> From the test I wonder if READ_UNCOMMITTED is actually meant to be a
> snapshot isolation against other transactions adding data after a
> READ_UNCOMMITTED connection has opened? So you can do dirty reads,
> but only from writes that happened before the connection was opened.
>
> Håvard
> _______________________________________________
> rdf4j-dev mailing list
> rdf4j-dev@xxxxxxxxxxx
> To change your delivery options, retrieve your password, or
> unsubscribe from this list, visit
> https://dev.eclipse.org/mailman/listinfo/rdf4j-dev