Connect to Neo4J Data as an External Data Source using PolyBase

PolyBase for SQL Server allows you to query external data by using the same Transact-SQL syntax used to query a database table. When paired with the CData ODBC Driver for Neo4J, you get access to your Neo4J data directly alongside your SQL Server data. This article describes creating an external data source and external tables to grant access to live Neo4J data using T-SQL queries.

NOTE: PolyBase is only available on SQL Server 19 and above.

CData Connect AI provides a pure SQL Server interface for Neo4J, allowing you to query data from Neo4J without replicating the data to a natively supported database. Using optimized data processing out of the box, CData Connect AI pushes all supported SQL operations (filters, JOINs, etc.) directly to Neo4J, leveraging server-side processing to return the requested Neo4J data quickly.

Configure Neo4J Connectivity for PolyBase

Connectivity to Neo4J from PolyBase is made possible through CData Connect AI. To work with Neo4J data from PolyBase, we start by creating and configuring a Neo4J connection.

1. Log into Connect AI, click Sources, and then click Add Connection

2. Select "Neo4J" from the Add Connection panel

3. Enter the necessary authentication properties to connect to Neo4J.

   To connect to Neo4j, set the following connection properties:

   • Server: The server hosting the Neo4j instance.
   • Port: The port on which the Neo4j service is running. The provider connects to port 7474 by default.
   • User: The username of the user using the Neo4j instance.
   • Password: The password of the user using the Neo4j instance.
   
4. Click Save & Test
5. Navigate to the Permissions tab in the Add Neo4J Connection page and update the User-based permissions.

Add a Personal Access Token

When connecting to Connect AI through the REST API, the OData API, or the Virtual SQL Server, a Personal Access Token (PAT) is used to authenticate the connection to Connect AI. It is best practice to create a separate PAT for each service to maintain granularity of access.

1. Click on the Gear icon () at the top right of the Connect AI app to open the settings page.
2. On the Settings page, go to the Access Tokens section and click Create PAT.
3. Give the PAT a name and click Create.
4. The personal access token is only visible at creation, so be sure to copy it and store it securely for future use.

With the connection configured and a PAT generated, you are ready to connect to Neo4J data from Polybase.

Create an External Data Source for Neo4J Data

After configuring the connection, you need to create a credential database for the external data source.

Creating a Credential Database

Execute the following SQL command to create credentials for the external data source connected to Neo4J data.

NOTE: Set IDENTITY to your Connect AI username and set SECRET to your Personal Access Token.

CREATE DATABASE SCOPED CREDENTIAL ConnectCloudCredentials
WITH IDENTITY = 'yourusername', SECRET = 'yourPAT';

Create an External Data Source for Neo4J

Execute a CREATE EXTERNAL DATA SOURCE SQL command to create an external data source for Neo4J with PolyBase:

CREATE EXTERNAL DATA SOURCE ConnectCloudInstance
WITH ( 
  LOCATION = 'sqlserver://tds.cdata.com:14333',
  PUSHDOWN = ON,
  CREDENTIAL = ConnectCloudCredentials
);

Create External Tables for Neo4J

After creating the external data source, use CREATE EXTERNAL TABLE statements to link to Neo4J data from your SQL Server instance. The table column definitions must match those exposed by CData Connect AI. You can use the Data Explorer in Connect AI to see the table definition.

Sample CREATE TABLE Statement

Execute a CREATE EXTERNAL TABLE SQL command to create the external table(s), using the collation and setting the LOCATION to three-part notation for the connection, catalog, and table. The statement to create an external table based on a Neo4J ProductCategory would look similar to the following.

CREATE EXTERNAL TABLE ProductCategory(
  CategoryId COLLATE [nvarchar](255) NULL,
  CategoryName COLLATE [nvarchar](255) NULL,
  ...
) WITH ( 
  LOCATION='Neo4j1.Neo4j.ProductCategory',
  DATA_SOURCE=ConnectCloudInstance
);

Having created external tables for Neo4J in your SQL Server instance, you are now able to query local and remote data simultaneously. To get live data access to hundreds of SaaS, Big Data, and NoSQL sources directly from your SQL Server database, try CData Connect AI today!