jexp

Maze with locked doors

Imagine a maze with rooms (nodes) and doors (relationships) between the rooms. The doors to some rooms are locked and their keys are held in other rooms (as properties).

In this gist model of the maze, you can reach room D by following the path A→B→C→A, picking up the key for room D in room B. However it is not possible to reach room F, since the key to room F is in room E, and the key to room E is in room D, and there is no way back from room D to room A, so room E is inaccessible. (Finding the HIDDEN door from room D to room C would make this possible.)

Is it possible to create queries which take into account the keys that can be picked up on the way? For example:

jexp

The Game of Thrones in Neo4j

The setup

 CREATE (westeros { name: "Westeros" })

jexp

= Untying the Graph Database Import Knot =

This Graphgist accompanies http://blog.bruggen.com/2013/12/untying-graph-database-import-knot.html[my blogpost of December 6th, 2013] which tries to explain the different types of questions that people should be asking themselves when thinking about importing data into http://www.neo4j.org[neo4j], and the tools that can contribute to finding the most optimal import strategy for your specific use case.

//setup
//hide
[source,cypher]
----
create (n1:Tool {id:'1',name:'Spreadsheets'}),
(n2:Tool {id:'2',name:'Cypher Statements'}),

jexp

A complex query result projection in cypher

Table of Contents

• Introduction

Introduction

Sometimes it is better to request a complete object-tree from the (graph-)database at once instead sending more than one requests to the database and merging the results in program code.

jexp

A sales funnel

CREATE (s:Stage{name:'Suspect'})
CREATE (mql:Stage{name:'Marketing Qualified Lead'})
CREATE (ssc:Stage{name:'Self-Serve Customer'})
CREATE (ec:Stage{name:'Existing Customer'})
CREATE (ecno:Stage{name:'Existing Customer-No Opportunity'})
CREATE (sql:Stage{name:'Sales Qualified Lead'})

jexp

package tests;

/**
 *
 * @author kb
 *
 */

import org.neo4j.cypher.ExecutionEngine;
import org.neo4j.cypher.ExecutionResult;

jexp

Game Of Life

Game of Life is mathematic toy world that was invented by John Horton Conway in 1970. Game of Life is played on a grid of cells that are either dead or alive by simluating how the world evolves over a series of rounds. In each round cells die, survive, or are reborn depending on the number of neighbours they have. You can find out more about Game of Life by watching the video below or reading up on it in Wikipedia.

jexp

= Graph Initialization

I'm using Neo4j 2.0.1 with Cypher over the Batch REST API.

//hide
//setup
//output
[source,cypher]
----
CREATE (u:user {id: "u1", name: "Bill"})-[:CONTACT]->(c:contact {id: "c1"})

jexp

= Using hierarchical facets 

We have a usecase with documents that are tagged with keywords in a theasaurus. This gists explains the model and is at the same time an invitation to suggest improvements. Because it would be nice to have something that performs better.

== The model

//setup
//hide
[source,cypher]
----

jexp

The World Cup Graph

Initial Data Setup