uPortal IRC Logs-2011-10-26

[09:22:33 CDT(-0500)] <EricDalquist> good moring'

[09:23:02 CDT(-0500)] <Arvids> good evening

[09:23:18 CDT(-0500)] <EricDalquist> that too

[09:23:42 CDT(-0500)] <Arvids> I just realized that import/export manual of uP40 is outdated

[09:23:53 CDT(-0500)] <Arvids> filing an issue now

[09:23:57 CDT(-0500)] <EricDalquist> yeah

[09:24:01 CDT(-0500)] <EricDalquist> I have that page open

[09:24:06 CDT(-0500)] <EricDalquist> and a todo to finish clearning it up

[09:24:11 CDT(-0500)] <EricDalquist> thanks for the jira issue though

[09:27:38 CDT(-0500)] <EricDalquist> on an unrelated rant ... I really wish hsqldb 2.2 had row level locking :/

[09:28:01 CDT(-0500)] <EricDalquist> without it I have to disable a few unit tests unless they are running against a 'real' db

[09:28:45 CDT(-0500)] <Arvids> concurrency issues?

[09:28:56 CDT(-0500)] <EricDalquist> working on the stats aggregation stuff

[09:29:07 CDT(-0500)] <EricDalquist> and as a pre-req I need a portable way to aquire a lock within a cluster

[09:29:11 CDT(-0500)] <Arvids> yeah, I saw previous commits

[09:29:31 CDT(-0500)] <EricDalquist> what I'm doing is using the JPA2 lock abilities

[09:30:10 CDT(-0500)] <EricDalquist> which on any DB other than hsqldb works great, it does a "select for update"

[09:30:22 CDT(-0500)] <EricDalquist> and holds the tx open until the work is complete

[09:30:48 CDT(-0500)] <EricDalquist> that should result in any other tx trying to do a select for update on that row to block

[09:30:53 CDT(-0500)] <EricDalquist> except on hsql

[09:30:56 CDT(-0500)] <EricDalquist> where it just doesn't

[09:31:29 CDT(-0500)] <Arvids> I believe you can't wish for everything from bundled database

[09:31:42 CDT(-0500)] <EricDalquist>

[09:31:45 CDT(-0500)] <EricDalquist> I know

[09:31:57 CDT(-0500)] <EricDalquist> really I'm just happy that they finally added true tx isolation in 2.2

[09:32:11 CDT(-0500)] <Arvids> btw, why derby is not used so extensively?

[09:32:32 CDT(-0500)] <Arvids> mostly I hear about hsql, but few years ago derby was very promising, too

[09:32:40 CDT(-0500)] <EricDalquist> don't know, I've never really looked into it

[09:34:03 CDT(-0500)] <EricDalquist> though looking at the DerbyDialect it appears to support row level locking

[09:38:25 CDT(-0500)] <Arvids> http://www.h2database.com/html/features.html#comparison says that hsqldb supports row level locking :S

[09:38:36 CDT(-0500)] <Arvids> *9 When using MVCC (multi version concurrency).

[09:40:00 CDT(-0500)] <EricDalquist> yeah

[09:40:21 CDT(-0500)] <EricDalquist> but from looking in the forums their "row level locking" isn't actual blocking

[09:41:11 CDT(-0500)] <Arvids> sad

[09:41:14 CDT(-0500)] <EricDalquist> hrm

[09:41:25 CDT(-0500)] <EricDalquist> though I'll give enabling MVCC a try

[09:44:17 CDT(-0500)] <EricDalquist> yup just enabled MVCC and still no blocking