Hi Mansi,
Here you have a natural partition of your data : the files you ingested.
So my first suggestion would be to query your data on a file basis:
for $doc in db:open(‘your_collection_name’)
let $file-name := db:path($doc)
return
file:write(
$file-name,
<names>
{
for $name in $doc//E/@name/data()
return
<name>{$name}</name>
}
</names>
)
Is it for indexing ?
Hope it helps,
Best regards,
Fabrice Etanchaud
Questel/Orbit
De : [email protected]
[mailto:[email protected]] De la part de Mansi Sheth
Envoyé : jeudi 6 novembre 2014 16:33
À : Christian Grün
Cc : BaseX
Objet : Re: [basex-talk] Out Of Memory
This would need a lot of details, so bear with me below:
Briefly my XML files look like:
<A name="">
<B name="">
<C name="">
<D name="">
<E name=""/>
<A> can contain <B>, <C> or <D> and B, C or D can contain E. We have 1000s
(currently 3000 in my test data set) of such xml files, of size 50MB on an
average. Its tons of data ! Currently, my database is of ~18GB in size.
Query: /A/*//E/@name/string()
This query, was going OOM, within few mins.
I tried a few ways, of whitelisting, with contain clause, to truncate the
result set. That didn't help too. So, now I am out of ideas. This is giving JVM
10GB of dedicated memory.
Once, above query works and doesn't go Out Of Memory, I also need corresponding
file names too:
XYZ.xml //E/@name
PQR.xml //E/@name
Let me know if you would need more details, to appreciate the issue ?
- Mansi
On Thu, Nov 6, 2014 at 8:48 AM, Christian Grün
<[email protected]<mailto:[email protected]>> wrote:
Hi Mansi,
I think we need more information on the queries that are causing the problems.
Best,
Christian
On Wed, Nov 5, 2014 at 8:48 PM, Mansi Sheth
<[email protected]<mailto:[email protected]>> wrote:
> Hello,
>
> I have a use case, where I have to extract lots in information from each XML
> in each DB. Something like, attribute values of most of the nodes in an XML.
> For such, queries based goes Out Of Memory with below exception. I am giving
> it ~12GB of RAM on i7 processor. Well I can't complain here since I am most
> definitely asking for loads of data, but is there any way I can get these
> kinds of data successfully ?
>
> mansi-veracode:BigData mansiadmin$ ~/Downloads/basex/bin/basexhttp
> BaseX 8.0 beta b45c1e2 [Server]
> Server was started (port: 1984)
> HTTP Server was started (port: 8984)
> Exception in thread "qtp2068921630-18" java.lang.OutOfMemoryError: Java heap
> space
> at
> java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject.addConditionWaiter(AbstractQueuedSynchronizer.java:1857)
> at
> java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject.awaitNanos(AbstractQueuedSynchronizer.java:2073)
> at
> org.eclipse.jetty.util.BlockingArrayQueue.poll(BlockingArrayQueue.java:342)
> at
> org.eclipse.jetty.util.thread.QueuedThreadPool.idleJobPoll(QueuedThreadPool.java:526)
> at
> org.eclipse.jetty.util.thread.QueuedThreadPool.access$600(QueuedThreadPool.java:44)
> at
> org.eclipse.jetty.util.thread.QueuedThreadPool$3.run(QueuedThreadPool.java:572)
> at java.lang.Thread.run(Thread.java:744)
>
>
> --
> - Mansi
--
- Mansi
