How to extract an entity relationship diagram from a graph database? I have all the required files that was created from my application.
You can use
call db.schema for a graph representation of the graph data model. There are a few other functions to get the properties, keys, indexes, etc like call db.indexes, call db.propertykeys etc.
The APOC procedure library has a few relevant functions that might help to get a tabular layout - or develop it yourself in Excel from the labels, property keys, etc.
You can also build a data model using the Arrows tool
Please reorient your thinking to use graph terms - the equivalent for the ER diagram would be a model built using the Arrows tool or the db.schema.
I used: CALL db.schema.visualization for visualizing the database schema. Like https://stackoverflow.com/a/45357049/7924573 already said, in graph databases this is as closest as you can to ER-diagrams. In the remote interface you can export it directly as e.g. .svg graphic
Here is an example:
Related
I'm new to neo4j and graph databases in general.
Given a complex Cypher query, that I don't want to store inside the application (or several applications), but keep centralized, what options are left to me?
In a SQL database I would use a stored function. Are UDF function the way to go in neo4j?
From the docs it seems to me that they're more a way to extend the database functionality by being able to access the graph internals, but I've just started studying them.
Take a look at the custom functions and procedures available in the apoc library.
https://neo4j.com/docs/labs/apoc/current/cypher-execution/cypher-based-procedures-functions/
CALL apoc.custom.asProcedure('answer','RETURN 42 as answer')
CALL custom.answer() YIELD row RETURN row.answer
I am new to Neo4j and I want to add a new node to an existing relationship using Structr platform.
This is the Cypher query that I tested in Neo4j web browser and it works.
match(projects:Project {name:'IRIS Recognition Java'})
create(client:Client {name:'Andreas Pal'}) CREATE(projects)-[w:IS_PART_OF]->(client)
return w
In the Structr platform I created a table that contains all the existing projects from database and I want to assign a member to the project.
I tried to put in a table date a query to bring also the clients. And I don't know how to create the assign. Any help would be very much appreciated. Thank you.
You need to use Structr's means of editing the data in the database. If you use Cypher directly, you are modifying the data on a different (wrong) level. You can either use Structr directly to create relationships, or you have to make the relationships in a way that Structr can detect and "see" those relationships.
Please have a look at https:/support.structr.com/article/295 for more information.
I have a small dataset loaded into Neo4J consisting of a 6 node labels with about 20 nodes for each label and there are about 10 different relationships. I was wondering if you can automatically create a picture of this data model using the data available in the database.
I would like to create something like this automatically from the data:
taken from http://neo4j.com/docs/stable/cypherdoc-movie-database.html
I know that it would be quite simple doing it manually in this example but it could come in handy looking at more complex data models.
Any suggestions?
Thank you Michael, that helped. There is also functionality in the web tool that ships with Neo4J that can do something similar although less graphically.
You click on the little bubbles in the top left corner of the interface and then there is a predefined query that extracts all lables and relations from the graph.
We are working on a system where users can define their own nodes and connections, and can query them with arbitrary queries. A user can create a "branch" much like in SCM systems and later can merge back changes into the main graph.
Is it possible to create an efficient data model for that in Neo4j? What would be the best approach? Of course we don't want to duplicate all the graph data for every branch as we have several million nodes in the DB.
I have read Ian Robinson's excellent article on Time-Based Versioned Graphs and Tom Zeppenfeldt's alternative approach with Network versioning using relationnodes but unfortunately they are solving a different problem.
I Would love to know what you guys think, any thoughts appreciated.
I'm not sure what your experience level is. Any insight into that would be helpful.
It would be my guess that this system would rely heavily on tags on the nodes. maybe come up with 5-20 node types that are very broad, including the names and a few key properties. Then you could allow the users to select from those base categories and create their own spin-offs by adding tags.
Say you had your basic categories of (:Thing{Name:"",Place:""}) and (:Object{Category:"",Count:4})
Your users would have a drop-down or something with "Thing" and "Object". They'd select "Thing" for instance, and type a new label (Say "Cool"), values for "Name" and "Place", and add any custom properties (IsAwesome:True).
So now you've got a new node (:Thing:Cool{Name:"Rock",Place:"Here",IsAwesome:True}) Which allows you to query by broad categories or a users created categories. Hopefully this would keep each broad category to a proportional fraction of your overall node count.
Not sure if this is exactly what you're asking for. Good luck!
Hmm. While this isn't insane, think about the type of system you're replacing first. SQL. In SQL databases you wouldn't use branches because it's data storage. If you're trying to get data from multiple sources into one DB, I'd suggest exporting them all to CSV files and using a MERGE statement in cypher to bring them all into your DB at once.
This could manifest similar to branching by having each person run a script on their own copy of the DB when you merge that takes all the nodes and edges in their copy and puts them all into a CSV. IE
MATCH (n)-[:e]-(n2)
RETURN n,e,n2
Then comparing these CSV's as you pull them into your final DB to see what's already there from the other copies.
IMPORT CSV WITH HEADERS FROM "file:\\YourFile.CSV" AS file
MERGE (N:Node{Property1:file.Property1, Property2:file.Property2})
MERGE (N2:Node{Property1:file.Property1, Property2:file.Property2})
MERGE (N)-[E:Edge]-(N2)
This will work, as long as you're using node types that you already know about and each person isn't creating new data structures that you don't know about until the merge.
I've generated a Neo4j graph and created visualization of the graph using the 'Style' rules on 'Data Browser'. I was able to display the properties of the Nodes. It looks like the style rules can only be applied to Nodes. However I want to display (visualize on data browser) the properties on the relationship. Is this possible? If so, how do I do it?
I read through the Neo4j documentation and also searched in the Neo4j forums but had no luck.
I appreciate any help.
TIA
For example:
(is a)
(Josh) --------------------> (Male)
(demographic=gender)
(created=09/25/12)
Where demographic, created are properties of the relationship 'is a'.
Well, since you extended the question to available options, not just Webadmin:
The Neo folks put up a side about visualization options: http://www.neo4j.org/develop/visualize
For your use case, try Neoclipse https://github.com/neo4j/neoclipse/downloads
it allows to specify which properties to display on nodes and relationship (be sure to enable the filters in the Graph Database View or the preferences won't have any effect). It look similar to the webadmin, but can be customized more.