Gonna be may 22nd ..I plan to cme by home over weekend
Sent from my T-Mobile 4G LTE Device.Samsung Galaxy™ S6 Edge. Jeryl Cook Founder & Chief Executive Officer VanitySoft, Inc. A G eo Business Intelligence Technology Consulting Firm www.vanity-soft.com www.linkedin.com/in/jerylcook Get answers to "who knew what, when, and where"... and everything in between. -------- Original message -------- From: [email protected] Date: 05/20/2015 4:59 PM (GMT-05:00) To: Digest recipients <[email protected]> Subject: [Neo4j] Digest for [email protected] - 9 updates in 4 topics [email protected] Google Groups Topic digest View all topics How to have Object-Graph mapping (OGM) as an analogous to Object-Relational mapping (ORM) ? - 1 Update How pattern matching works? - 5 Updates Socket issues - neo4j/OS config - 2 Updates Resources locked by a failed transaction are not released [py2neo, neo4j 2.1] - 1 Update How to have Object-Graph mapping (OGM) as an analogous to Object-Relational mapping (ORM) ? Gelli Ravikumar <[email protected]>: May 20 10:19PM +0530 Hello to all, I am looking for the concept of how to develop a Object-Graph mapping (OGM) as an analogous to Object-Relational mapping (ORM). However, I have came across some information from these links: 1. http://py2neo.org/2.0/ext/ogm.html 2. http://nigelsmall.com/py2neo/1.6/ogm/ 3. http://www.slideshare.net/neo4j/ogm-withsdn30 4. https://vimeo.com/80618455 5. https://github.com/spring-projects/spring-data-neo4j/tree/4.0/neo4j-ogm/src/main/java/org/neo4j/ogm 6. But, if there are any other references to get to know a deeper understanding of OGM, please post them here. Also, if there are any comparisons for ORM and OGM, please let me know. Thanks so much for your reply! -- with Regards ---------------------------------------------------- Gelli Ravikumar Research Scholar (Ph.D), Field Computations Lab, Dept. of Electrical Engineering, IIT Bombay, Powai, Mumbai 400076 Ph: 022-2576 4424, 089 765 983 96 My publications: http://tinyurl.com/gelliPapers Gandhian Young Technological Innovation Award - 2013 POSOCO Power System Award: PPSA - 2013 IITB PhD Executive Member - 2013-14 IITB SARC Core Technical Member - 2014-15 Back to top How pattern matching works? Sumit Gupta <[email protected]>: May 19 02:43PM -0700 Hi Martin, Did you consulted the Docs - http://neo4j.com/docs/stable/tutorial-traversal-concepts.html http://neo4j.com/docs/stable/tutorial-traversal-java-api.html. Traversal API defines various ways to include/ exclude nodes and various other critrieas to define the scope of your traversals. Also for finding the distance between 2 given Nodes you can use different Graph Algorithms - http://neo4j.com/docs/stable/tutorials-java-embedded-graph-algo.html Thanks, Sumit On Tuesday, 19 May 2015 10:01:30 UTC-7, Martin Troup wrote: Martin Troup <[email protected]>: May 19 03:18PM -0700 Hi Sumit, thanks for your reply at first! I have went through the docs and I familiar with the way how to use the framework. But that was not my question. Let me describe it in a better way and sorry for that confusion: I want to know what exactly happens when I execute this cypher query: MATCH (a)--(b)--(c)--(a) RETURN a, b, c At first I thought such query is somehow transformed in non-declarative way so Traversal API could handle it (thats why I have looked at the Traversal framework at the beginning). But maybe there is a different way how this query is actually processed. I would like to know how the whole process of pattern matching works, so I can estimate its algorithmic complexity. I am a student and I am currently writing a part of my master's thesis where I focus on algorithmic complexity of general pattern (meaning no specific information is added when querying) matching in Neo4j. Dne úterý 19. května 2015 23:43:10 UTC+2 Sumit Gupta napsal(a): Michael Hunger <[email protected]>: May 20 10:17AM +0200 Cypher doesn't use the traversal framework it has its own operations (expand, expand(into), etc) that, depending on your query, bound nodes and relationships, filters, and database statistics will combine differently into a query execution? You see it best in the visual query plan of your query. And in the manual: http://neo4j.com/docs/stable/execution-plans.html <http://neo4j.com/docs/stable/execution-plans.html> Cheers, Michael Martin Troup <[email protected]>: May 20 03:17AM -0700 Thanks Michael, that helps a lot! One more question then. When I want to compare two Cypher queries that do the same thing... Is there any relevant metric I can use to compare those queries? So I can say which one is easier to execute? I have already measured execution time for both of them, but I would also like to compare how complex they are. Maybe total number of DbHits for each query? Would that be relevant? Thanks, again, for your answer. Dne středa 20. května 2015 10:17:52 UTC+2 Michael Hunger napsal(a): Michael Hunger <[email protected]>: May 20 01:18PM +0200 If you run your queries with EXPLAIN you see estimated db-hits and estimated rows or with PROFILE you see also real db-hits and total db-hits In the bin/neo4j-shell you get textual output and in browser visual output. Michael Back to top Socket issues - neo4j/OS config Kevin Eid <[email protected]>: May 20 12:50AM -0700 Hi, I'm building a log generator app using multithreading and creating nodes and rels from these data. I'm having the following issue: *"I/O exception (java.net.SocketException) caught when processing request: Socket closed"* I'm trying to change the config of my debian VMs (like timeout sockets, ...). Do you have any idea how to solve it? Do I need to change the neo4j.properties files or the OS config? Thanks in advance for your feedbacks, Kevin Michael Hunger <[email protected]>: May 20 10:19AM +0200 Kevin, we need much more detail than that. Neo4j version how you interact with it, your stack your code, what do you send how to Neo4j full error message messages.log of Neo4j Michael Back to top Resources locked by a failed transaction are not released [py2neo, neo4j 2.1] Guilherme Dinis Junior <[email protected]>: May 19 08:18AM -0700 I noticed this behavior while using py2neo 2.0.6, when I attempt to create a Node that violates a unique constraint. Nigel suggested I bring it up here. Problem: -------------- When a transaction attempts to create a resource with a unique constraint, if the transaction fails with a `py2neo.cypher.error.schema.ConstraintViolation` error, any subsequent transactions that attempt to use the resource fail. Steps: --------- 1. Create unique constraint on a label, e.g. Person (name) 2. Create a node (Person {name: "John"}) using the `CypherTransaction` 3. Attempt to create a node with the same name: (Person {name: "John"}), py2neo throws a `py2neo.cypher.error.schema.ConstraintViolation`, from Neo4j 4. Attempt to delete the node, it fails with a `SocketTimeoutError` To prevent the SocketTimeout error, one must rollback the transaction, that's `tx.rollback()`, before attempting step 4. I'm not sure if this is intentional, so we can control our transactions ourselves. But it leaves the db in an inconsistent state if we don't rollback the transaction. Maybe for certain cases, like `ConstraintViolation` errors, the transaction could be automatically rolled back. Is this made intentional, and if so, may I ask why? Thanks Original post is here <https://github.com/nigelsmall/py2neo/issues/396> Back to top You received this digest because you're subscribed to updates for this group. You can change your settings on the group membership page. To unsubscribe from this group and stop receiving emails from it send an email to [email protected]. -- You received this message because you are subscribed to the Google Groups "Neo4j" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. For more options, visit https://groups.google.com/d/optout.
