Added, with patch file, at
https://issues.apache.org/jira/browse/JENA-134
I have made no more progress on testing it out other than sdbconfig so
far, hope too soon.
On 09/09/11 16:43, Paolo Castagna wrote:
Hi,
why don't you open a new JIRA issue (as a New Feature) for this?
https://issues.apache.org/jira/browse/JENA
You can then attach a patch to it. This way others can look at what you have
done so far (and maybe help you out).
Thanks for your help,
Paolo
nat lu wrote:
I made a start, and tried to use one of the existing flavours, but ended
up creating one for MonetDB - combination of derby and DB2. It doesnt
like longs or unbounded varchars.
So, I got as far as getting SDBConfig to complete, but havent done an
sdbload yet
On 09/09/11 10:37, Andy Seaborne wrote:
On 04/09/11 13:03, nat lu wrote:
I'm going to give it a go sometime soon and report back on my
non-scientific findings. Your point about the small number of columns is
well made, but the research paper cited earlier also mentions this and
reports that because of column store optimisations even when they
vertically partitioned their data rather than using a property-table
approach they still saw good improvement. However, again, I'm no column
store expert so perhaps I'm missing some point here :-). Anyway, time to
"suck it and see@, all in the name of progress of course.
On 03/09/11 16:29, David Jordan wrote:
I have not used a column-oriented database, but I am somewhat familiar
with them. My understanding of them is that the storage is partitioned
on a column basis, such that there is no physical clustering together
of all the columns for a given row. An advantage of this would be in
the case where you have tables with many columns, but the particular
application only needs a small subset of columns.
With the SDB representation of triples (3 columns) and quads (4
columns), and access typically based on having a specific value for
one or two of the columns, I am not so sure that a column-based
approach would offer any advantage.
But again, I am no expert on these types of databases.
These discussions about alternative datastore representations RDF/OWL
data are very useful, to gain better understanding of which data
architectures yield the best implementation approach for
high-performance.
p.s. I Monet provides support for JDBC, I would not think much effort
is needed to support in with SDB.
Shouldn't be too hard :-) SDB targets SQL-92 and there are a few
extension points to cope with the vagaries of different SQL engines.
It's one of the reasons there are ~10 small files to write, to capture
the uniqueness of each SQL syntax.
Andy
