I am a relative newbie to the world of cypher programming, and therefore hoping for a solution to this problem from the experts community here.
I am creating a graph from an excel file, which contains different categories, items and so on. One item can belong to multiple categories and so on.
I have generated the relevant create relationship statements (there are about 200 of them). However, when i put them through neo4j browser, the interface complains that i can only run one match - create command at a time.
i am not using any other programming language or their API and simply using neo4j browser to achieve this.
Kindly suggest path forward.
my env : neo4j desktop 4.1.3 on Windows 10 Enterprise.
apoc plugin is enabled, but i m not using it yet.
Thanks
raghav
By default, Neo4j Browser only allows one Cypher statement to be executed at a time. This can be changed by going to the browser settings on the sidebar (gear icon), and then checking the Enable multi statement query editor checkbox. Afterward, you should be able to execute multiple Cypher statements on the query editor.
Related
I need to share a Neo4J graph visualization with end users. They should be able to interact with the graph, and perform some very basic querying. For example:
- show me the relationships up to 3 hops away from node named 'Joe'
A first option would be to just give them the standard user interface (usually exposed at port 7474); however this is too powerful as they could perform anything in Cypher.
Is there any way of restricting this interface (so that they cannot trigger expensive queries or even graph updates)? Or maybe other open source / community alternatives?
Thanks
If you are using the Enterprise Edition of neo4j, you will have access to extensive authentication and authorization capabilities, including the ability to assign a reader role to specific user names.
If you do want to use the standard browser interface, you can apply some settings on the neo4j.conf file that may help you out:
dbms.transaction.timeout=10s
dbms.read_only=true
dbms.transaction.timeout will terminate queries exceeding the timeout, so that can prevent expensive queries.
dbms.read_only makes the entire db instance read-only.
You may also build a custom web UI that calls the REST endpoint (need to auth in headers)
or
create an unmanaged extension
https://neo4j.com/docs/java-reference/3.1/#server-unmanaged-extensions
I suggest you the chapter 8 of the excellent book Learning Neo4j, by Rik Van Bruggen. This book is available for download at Neo4j web site.
One of the sections of this chapter shows some open source visualization libraries and visualization solutions.
EDIT 1:
Analyzing a bit more the chapter 8 of the Learning Neo4j book I believe that a promising tool for your use case is the paid solution Linkurio.us (you can run a demo in the site). This solution has a native integration with Neo4j and others graph databases.
EDIT 2:
Alternatively you can build your own visualization solution with a graph visualization library in JavaScript, for example. Here a very useful answer from another StackOverflow question that lists more some libraries that can help you.
I have five relationships in the database, all created in the past. Four are empty, not attached to any node. How can I delete them? I want to keep only the one I am currently using and is attached to the nodes.
Neo4j does not offer a direct way to get rid of labels or relationship types that are no longer in use. However you can use the batch inserter API as a offline tool to copy over the contents of your db into a fresh one.
Luckily Michael has already written a tool doing this, check out https://github.com/jexp/store-utils. Be sure to bump the Neo4j version in pom.xml to the one you're currently using.
It seems that this is a problem with one single radical solution so far: to erase physically the database folders and files. Which I don't like it at all.
I'm using neo4j 2.1.2 community edition. I have loaded the CSV file which is having 2500 rows and i have created nodes and relationships among the columns. When i run the below cypher query
match (n) return count(*);
I'll get the nodes count as 17275. So when i match the nodes like match (n) return n and try to get the corresponding graph in a neo4j browser, it says
Resultset too large (over 1000 rows)
I know it's due to the nodes requested is more than 1000. So if i want to see the complete graph in neo4j browser, how can i do it?
The same query i tried in the neo4j web-admin, i wan able to get the data in tabular format but i wanted to see the data as a graph.
Also I'm not able to find neo4j-Shell in my neo4j installation bin directory. Why is that?
Thanks
Update 1
The Neo4J Web UI is built on top of D3.js using SVG: due to SVG performances in a browser when you have more than 500 nodes in a network, the user experience starts to degrade quite quickly.
Handling more than 1000 nodes adds to the technical challenge: in fact with so many nodes what happens most of the time is the "hairball" effect.
This is a blog post that might be useful (disclaimer: I am a developer for KeyLines) about visualizing big network with some design hints.
As you can imagine visualizing more than 1000 nodes is not that easy and that's why some companies such Cambridge Intelligence (KeyLines), Tom Sawyer (Perspective) or Linkourius came up with specific products for that.
You can of course build the visualization yourself for fun with open source libraries but keep in mind that it can take a very long time.
If your Neo4J project is not commercial I can suggest to have a look to Gephi to visualize it: it is a Desktop Application and it has a Neo4J adapter plugin. It can easily handle huge datasets but of course it lacks the same portability of a webapp.
In case you need ONLY a storage for your graph/data than a visualization is not required, you're right.
Original Answer
I think you might have to implement a custom visualization too see such graph in the browser, using one option of those in this page: http://www.neo4j.org/develop/visualize .
Alternatively have a look to this most extensive list here: Big data visualization using "search, show context, and expand on demand" concept
Or maybe have a different visualization approach with one of the following: Data Visualization libraries
Look at settings in neo4j browser. You can change Graph Visualization how you like. But browser can work much slower if you wanna see the complete graph.
I created an application which embedded Neo4j. In that application I created and stored some nodes with some relationships. My application has saved this database to a file. I would like to visualise that data. I know I can see graphs if I fire up the Neo4j server but I do not know how to import my neo4j.db file into the Neo4j server so that I can visualise it. Any suggestions would be greatly appreciated.
Depending on your use case you might have different solutions:
Use a web-based visualization
Use a desktop application to visualize your data
Use web-based visualization
In this case you have to take care of the web-app to visualize the data.
You have basically two solutions out there: Javascript or Java applets.
For the Javascript side you have many choices: D3js, VivaGraph, SigmaJS, KeyLines.
The first three are open source and free while the last one has a commercial licence and non-free.
There're already a million questions about these libraries on SO, so I'll link you to some of those to understand the various differences.
Desktop Application
The main solutions in this case I would recommend you, depending on the kind of data are: either Gephi or Cytoscape.
In both cases I believe you have to write your own adapter to communicate with your application.
Architecture Reference
The architecture in both cases will be the following:
The controller renders a webpage with the JS visualisation framework you want to use
The controller offers a couple of JSON endpoints the client can use to query the data from the Neo4J embedded
Each query fetch the data, put in a model and render the JSON to send to the client
If you're NOT using neo4j 2.0+ then really good way to visualize your graph is by using neoclipse. https://github.com/neo4j-contrib/neoclipse/downloads
it's really handy and it has cypher support too.
Or
another quick hack is to copy your db folder (which you created by using embedded database) into $NEO4j_HOME/data/
and
change $NEO4j_HOME/conf/neo4j-server-properties file to point to
and
start your server (bin/.neo4j start). You'll be able to visualize your database at localhost:7474
I hope it helps!
Assuming i am working with neo4j, the only way i can think of that would visualize my mock up data is to generate cypher code and paste it into neo4j's data browser
Is there another (better, simplier?) way one can use to create visualization without using cypher? Generating cypher code seems like a complex enough task by itself.
Writing tests is of course another way of making sure relationships are set up right, but as i am learning the system, i'd like to visually see things to make sure they are set up as expected.
This gist contains an example on how to use the Neo4J Graphviz component to generate output in Graphviz DOT notation, which is supported by a range of graph visualizing software. (And of course Graphviz itself)
(Link to the original blog post where I found the example: http://blog.neo4j.org/2012/05/graph-this-rendering-your-graph-with.html)
There is a new solution to explore the content of a Neo4j graph database using a web browser: http://linkurio.us/
It allows you to search nodes by properties, inspect nodes, expand neighborhood...
Disclamer: I'm co-founder of Linkurious and Gephi.
There are some options listed on http://www.neo4j.org/develop/visualize also.