Graph Data Processing with Cypher by Ravindranatha Anthapu

Author:Ravindranatha Anthapu
Language: eng
Format: epub
Publisher: Packt Publishing Pvt. Ltd.
Published: 2022-12-02T00:00:00+00:00

Figure 6.12 – Usage of list comprehensions and the reduce function

We can see from the result that we can get a single by filtering the list for even numbers from the original list and using the reduce function to calculate the sum of squares.

We will take a look at using UNION cypher queries in the next section.

Working with UNION in Cypher

The UNION clause combines the results of two or more queries and returns the results. It works pretty similarly to how it works in SQL queries. Normally, we use the UNION clause when we want to combine the results of multiple, disparate queries returning similar datasets.

Let’s look at an example usage of the UNION clause:

MATCH (p:Patient)-[:HAS_ENCOUNTER]->()-[:HAS_DIAGNOSIS]->(d) WHERE p.id='f237e253-9052-a038-7c9e-dbd9a1d7da32' RETURN d.code as drug UNION MATCH (p:Patient)-[:HAS_ENCOUNTER]->()-[:HAS_DIAGNOSIS]->(d) WHERE p.id='ffa580de-08e5-9a47-b12a-db312ad6825b' RETURN d.code as drug

This query returns the diagnosis codes used among two patients, as shown in the following figure:

Download

Copyright Disclaimer:
This site does not store any files on its server. We only index and link to content provided by other sites. Please contact the content providers to delete copyright contents if any and email us, we'll remove relevant links or contents immediately.