[Neo4j] All simple paths algorithm

Dear Sir / Madam, Let me introduce myself. I'm an IT engineer and currently working for an university project related to development of knowledge discovery and semantic associations evaluation system. Due to that I'm interested in principle of your algorithm's design (eo4j::Algo.shortest_paths -

Re: [Neo4j] setProperty Exception

Hi John, maybe you are trying to add a property that has a value of String[] with at least one of the array members being null?. That would cause the first exception. The second exception is most probably because you try to success() and finish() your transaction even after the exception. For

Re: [Neo4j] All simple paths algorithm

Hi Piotr, Neo4j is an open source product. This means you're quite welcome to read the source of the algorithm and see how it works directly. The implementation for all of our shortest path algorithms can be found here:

Re: [Neo4j] IMDB Error 503 in setup.html

thank you! it works :) franz -- View this message in context: http://neo4j-community-discussions.438527.n3.nabble.com/IMDB-Error-503-in-setup-html-tp3281457p3283655.html Sent from the Neo4j Community Discussions mailing list archive at Nabble.com. ___

Re: [Neo4j] IMDB Error 503 in setup.html

Glad to help! /peter On Thu, Aug 25, 2011 at 1:38 PM, elfranco f.ruff...@gmail.com wrote: thank you! it works :) franz -- View this message in context: http://neo4j-community-discussions.438527.n3.nabble.com/IMDB-Error-503-in-setup-html-tp3281457p3283655.html Sent from the Neo4j

Re: [Neo4j] All simple paths algorithm

2011/8/25 Jim Webber j...@neotechnology.com Hi Piotr, Neo4j is an open source product. This means you're quite welcome to read the source of the algorithm and see how it works directly. The implementation for all of our shortest path algorithms can be found here:

Re: [Neo4j] Neo4jPHP batch insert benchmarks

Josh, it might be that the parsing of the JSON load is taking up increasingly much time when you get big batches. At least that is my suspicion. Also, that might be the reason for the heap problems - basically the String parsing is taking over :/ Do you have any means of verifying that? Cheers,

[Neo4j] Performance Benchmarks Available

We are looking for neo4j performance benchmarks vs rdbms and nosql data stores; are there any available? Thanks raffi -- This e-mail transmission may contain information that is proprietary, privileged and/or

Re: [Neo4j] Performance Benchmarks Available

Hi! Here's articles which make some kind of comparison: http://www.delicious.com/neo4j/articles+comparison If anyone else know about other articles on this topic, please tell me! /anders On 08/25/2011 03:15 PM, Basmajian, Raffi wrote: We are looking for neo4j performance benchmarks vs rdbms

Re: [Neo4j] Neo4jPHP batch insert benchmarks

Hey Peter, I don't have any way of verifying on the server side, other than measuring the time it takes for curl_exec to return a response. On the client side I can see that PHP's json_encode/json_decode functions are taking less than .5% of the total run time, even with a batch size of 1.

Re: [Neo4j] Performance Benchmarks Available

Hi, I did not find any useful performance benchmarks at that link, just articles about how and why graph-style data bases perform better than SQL-based data stores. -Original Message- From: user-boun...@lists.neo4j.org [mailto:user-boun...@lists.neo4j.org] On Behalf Of Anders Nawroth

Re: [Neo4j] Test and try/catch block

If you're using the standard try/catch/finally idiom in Neo4j then consider using Nat Pryce/Steve Freeman's transactor pattern. We have an example of this in the neo4j server code here:

Re: [Neo4j] Performance Benchmarks Available

Hi Raffi, There are no standard TPC-like benchmarks for Neo4j. However, for even modest data sets, Neo4j can be orders of magnitude faster than some SQL-oriented databases primarily because it avoids join pain (no sets) for connected data. There are a few slides in the tutorial deck about this

Re: [Neo4j] Neo4jPHP batch insert benchmarks

The heap space stuff would make sense I think, because we currently deserialize and serialize in-place, keeping the whole thing in memory. Would be interesting to see if we could implement a setup that can stream the deserialization/serialization, getting rid of the memory overhead.. You said you

Re: [Neo4j] Neo4jPHP batch insert benchmarks

Hey Josh, You can validate what Peter's suggesting by setting a small heap when you run the server. If you edit conf/neo4j-wrapper.conf you can override the property for heap size with something like this: wrapper.java.maxmemory=1 Then you should (in theory) be able to see the batch

[Neo4j] Executing arbitrary code through REST (was: Specifying best first order of traverse over REST API)

Guys, with the custom sorting in Lucene and this thread coming up all the time, I took the time to document the execution of arbitrary Groovy and thus, Java calls through REST. In the example below, there are calls to Neo4j APIs, Gremlin stuff and custom sorting using Lucene classes, and return of

Re: [Neo4j] Specifying best first order of traverse over REST API

See the other mail for a pointer :) Cheers, /peter neubauer GTalk: neubauer.peter Skype peter.neubauer Phone +46 704 106975 LinkedIn http://www.linkedin.com/in/neubauer Twitter http://twitter.com/peterneubauer http://www.neo4j.org - Your high performance

Re: [Neo4j] Neo4jPHP batch insert benchmarks

Jim, When I was running into the issue, I set the maxmemory=256 and can confirm that it took much longer to fail, but it did fail in the same way. I didn't think of setting it smaller than the default, but I suspect you are correct. I'll try it that way when I attempt to generate the stack

Re: [Neo4j] Specifying best first order of traverse over REST API

Thanks Peter, we'll look into Gremlin. =) But I'll push back a bit and say it would still ask for a feature like this to be a first-class feature of the REST API. If my app is e.g. in Python, it's not super API-friendly for me to have to write Java-ish code to achieve what I want. I'd get it if

Re: [Neo4j] Specifying best first order of traverse over REST API

Aseem, If you can provide a nice suggestion on how exactly it would look, maybe I can implement it if the others agree? /peter Sent from my phone. On Aug 25, 2011 7:19 PM, Aseem Kishore aseem.kish...@gmail.com wrote: Thanks Peter, we'll look into Gremlin. =) But I'll push back a bit and say

Re: [Neo4j] Specifying best first order of traverse over REST API

Okay! Will think about this and get back to you soon. Peter, I gotta say -- your open-mindedness and willingness to help developers like me is awesome and much appreciated. Customer satisfaction, etc. =) Cheers, Aseem On Thu, Aug 25, 2011 at 11:12 AM, Peter Neubauer

[Neo4j] Cypher: how would you query first- and second-degree friends?

Man, I am loving Cypher. Thanks so much guys for introducing it. I'm a bit stuck on one query, though, and I wanted to ask for help. I think the reasons I'm stuck are related to the two feature requests I made yesterday (optional matches, and returning IDs). I want to fetch first- and

Re: [Neo4j] Cypher: how would you query first- and second-degree friends?

Good and valid requests, Aseem. Consider them heard. We'll see how soon we can get it to you. Andrés On Thu, Aug 25, 2011 at 12:57 PM, Aseem Kishore aseem.kish...@gmail.comwrote: Man, I am loving Cypher. Thanks so much guys for introducing it. I'm a bit stuck on one query, though, and I

[Neo4j] Wishlist: subgraphs over REST API

Sorry if I'm inundating the list w/ too many emails. =D I've been loving Cypher -- way more user-friendly and powerful than the REST API's traverse method -- but I'm finding even Cypher isn't optimized for queries where I really want to fetch a *subgraph*, not tabular data. I can give plenty of

Re: [Neo4j] Cypher: how would you query first- and second-degree friends?

Thanks Andrés! Couple of random extensions to the thoughts above: - To be consistent, perhaps for optional matches, the results could always include a row where that optional match was ignored. That way, Elizabeth, null wouldn't be an inconsistency; *every* first-degree friend would have an

Re: [Neo4j] Server couldn't start after java.lang.OutOfMemoryError

Hey Jim, It happened again and I'm pretty sure there was no other server process running. Also this time when it crashed I saw this line in the console log (not seeing this previously): Could not load hsdis-.jnilib; library not loadable; PrintAssembly is disabled When I tried to restart,

Re: [Neo4j] Neo4jPHP batch insert benchmarks

I bumped the maxmemory up to 512 and ran a batch to create 10 nodes (repeated 10 times). After an average of 20 seconds, I always received the following response: HTTP/1.1 100 Continue HTTP/1.1 500 Java heap space Content-Type: text/html; charset=iso-8859-1 Cache-Control: