Yep, your use case is a good fit for using indexes... looping through 300k
nodes just to find one particular isn't very efficient. Take a look at
http://components.neo4j.org/neo4j.py/ for how to use indexing in the neo4j
python bindings.
2010/10/5 Francois Kassis <francois_kas...@hotmail.com>
> Hi all,
> I am trying to retrieve data from neo4j database using python version.
> I have over 300000 nodes all joined to a master node by a OFTYPE
> relationships.
>
> I used the following to traverse it:
>
> #!/usr/bin/env python
> # -*- coding: UTF-8 -*-
> # Traversal
> import neo4j
>
>
> def get_OFTYPE(ar_node):#, ar_filter):
> return OFTYPE(ar_node)
>
> class OFTYPE(neo4j.Traversal):
> # my_pos_filter = ""
> #
> # def __init__(self, start, pos_filter=""):
> # # set an internal variable
> # self.my_pos_filter = pos_filter
> # neo4j.Traversal.__init__(self, start)
>
> types = [
> neo4j.Incoming.OFTYPE,
> ]
> order = neo4j.BREADTH_FIRST
> stop = neo4j.StopAtDepth(1)
>
> def isReturnable(self, position):
> return (not position.is_start
> # and position.label == self.my_pos_filter
> and position.last_relationship.type == 'OFTYPE')
>
>
>
> and call the above by:
>
> #!/usr/bin/env python
> # -*- coding: UTF-8 -*-
>
> import argparse
> import neo4j
> import ConfigParser
> import os, sys, datetime, string
> import neoentity_traverse_test
> from neo4j.util import Subreference
>
> def main():
> ls_current_script_path = sys.path[0] # os.getcwd()
> ls_current_script_filename = sys.argv[0]
>
> config = ConfigParser.RawConfigParser()
> config.read(ls_current_script_path + '/' + 'neoentity.cfg')
>
> parser = argparse.ArgumentParser(description='Initialize neo4j database
> for mediasharks root enteties. NOTE: if the database '\
> 'does not exists, it will simply be
> created.')
> parser.add_argument('--neodbpath', dest='neodbpath',
> metavar='NEODB-PATH',
> default=config.get('database', 'database_path'),
> help='a directory where neodb should be created or
> opened.')
> parser.add_argument('--classpath', dest='kernalclasspath',
> metavar='KERNAL-CLASSPATH',
> default=config.get('neo4j', 'kernalclasspath'),
> help='the path toneo4j kernal path.')
> parser.add_argument('--jvm', dest='jvmclasspath',
> metavar='JVM-CLASSPATH',
> default=config.get('jvm', 'jvmpath'),
> help='the path toneo4j kernal path.')
>
> args = parser.parse_args()
> pytest(args.neodbpath, args.kernalclasspath, args.jvmclasspath)
>
>
> def pytest(arg_neodb_path, arg_kernal_classpath, arg_jvm_classpath):
> print "====================================================="
> print "initializing neo4j db using parameters:"
> print "database-path = " + arg_neodb_path
> print "kernel-path = " + arg_kernal_classpath
> print "jvm-path = " + arg_jvm_classpath
> print "====================================================="
>
> #initialize variables
> ls_message = ""
>
> #create new neo database
> graphdb = neo4j.GraphDatabase(arg_neodb_path,
> classpath=arg_kernal_classpath, jvm=arg_jvm_classpath)
>
> #start new transaction
> try:
> tx = graphdb.transaction.begin()
>
> rootindex = graphdb.index("root_index", create=True)
> subbrandnode = rootindex["subbrand"]
> referencenode = graphdb.node[0]
>
>
> li_index = 0
> ls_filter = "PEPSI"
> for node in neoentity_traverse_test.get_OFTYPE(subbrandnode):#,
> ls_filter):
> ls_result = node["label"]
> if ls_result.startswith(ls_filter):
> li_index = li_index + 1
> print ls_result
> print li_index
>
> except:
> tx.failure()
> print "Error occurred, exiting..."
> raise
> else:
> tx.success()
> finally:
> tx.finish()
>
> #saving current transactions and closing current database
> graphdb.shutdown()
>
>
> if __name__ == '__main__':
> main()
>
> The problem is it's taking too much time. how can I improve performance and
> how can I use or call the lucene indexer from within python.
> THX in advance.
>
> Francois.
> _______________________________________________
> Neo4j mailing list
> User@lists.neo4j.org
> https://lists.neo4j.org/mailman/listinfo/user
>
--
Mattias Persson, [matt...@neotechnology.com]
Hacker, Neo Technology
www.neotechnology.com
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