Book Image

Graph Data Processing with Cypher

By : Ravindranatha Anthapu
Book Image

Graph Data Processing with Cypher

By: Ravindranatha Anthapu

Overview of this book

While it is easy to learn and understand the Cypher declarative language for querying graph databases, it can be very difficult to master it. As graph databases are becoming more mainstream, there is a dearth of content and guidance for developers to leverage database capabilities fully. This book fills the information gap by describing graph traversal patterns in a simple and readable way. This book provides a guided tour of Cypher from understanding the syntax, building a graph data model, and loading the data into graphs to building queries and profiling the queries for best performance. It introduces APOC utilities that can augment Cypher queries to build complex queries. You’ll also be introduced to visualization tools such as Bloom to get the most out of the graph when presenting the results to the end users. After having worked through this book, you’ll have become a seasoned Cypher query developer with a good understanding of the query language and how to use it for the best performance.
Table of Contents (18 chapters)
1
Part 1: Cypher Introduction
4
Part 2: Working with Cypher
9
Part 3: Advanced Cypher Concepts

Using index hints

Index hints are used to specify which indexes the planner should try to use. This can change how the query gets executed. There might be a trade-off compared to the default planning when using index hints.

We can provide index hints to the planner with a USING clause. Let’s take a sample query that uses multiple entities and review a basic query profile and index hint driver query profile:

MATCH path=
(p:Patient {id:'7361ce15-cf67-ae76-88e6-bcbdca19ce0b'})
-[:HAS_ENCOUNTER]->()
-[:HAS_DRUG]->(d:Drug {code:'1190795'})
RETURN path LIMIT 1

We will take the preceding query and get a basic query profile first:

PROFILE MATCH path=
(p:Patient {id:'7361ce15-cf67-ae76-88e6-bcbdca19ce0b'})
-[:HAS_ENCOUNTER]->()
-[:HAS_DRUG]->(d:Drug {code:'1190795'})
RETURN path LIMIT 1

The following screenshot represents a basic query profile:

Figure 9.11 – Basic query profile without hints...