3 Your first steps with the Cypher query language

 

This chapter covers

  • Introducing the Cypher query language syntax
  • Creating nodes and relationships with Cypher
  • Matching and retrieving data from the database
  • Removing properties and deleting nodes and relationships
  • Best practices for importing a CSV into a graph database

So far, you have learned a bit of graph theory and how to approach the property graph modeling process. Now, you will begin to learn how to perform network analysis through practical use cases. To follow the examples in this book, you need to set up a Neo4j development environment. If you need some help with the setup, I have added the Neo4j Development Environment appendix to help you get started.

This chapter will introduce Cypher query language clauses and best practices for importing data into a graph database. First, I will do a quick recap of using Cypher query language syntax to represent networks in a textual format. If you are already familiar with the Cypher query syntax, you can skip most of the chapter and just import the data as shown in the last section. Remember from the previous chapter, the Cypher syntax uses parenthesis to encapsulate a representation of a node.

Figure 3.1. Cypher query language syntax to represent a node with its label and properties
CH03 F01 cyphernode

3.1 Cypher query language clauses

3.1.1 CREATE clause

3.1.2 MATCH clause

3.1.3 WITH clause

3.1.4 SET clause

3.1.5 REMOVE clause

3.1.6 DELETE clause

3.1.7 MERGE clause

3.2 Importing CSV files with Cypher

3.2.1 Cleanup the database

3.2.2 Twitter graph model

3.2.3 Unique constraints

3.2.4 LOAD CSV clause

3.2.5 Importing the Twitter social network

3.4 Summary

3.5 Solutions to exercises