Connect to Everhour 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 Everhour, you get access to your Everhour data directly alongside your SQL Server data. This article describes creating an external data source and external tables to grant access to live Everhour 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 Everhour, allowing you to query data from Everhour 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 Everhour, leveraging server-side processing to return the requested Everhour data quickly.

Configure Everhour Connectivity for PolyBase

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

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

2. Select "Everhour" from the Add Connection panel

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

   Start by setting the Profile connection property to the location of the Everhour Profile on disk (e.g. C:\profiles\Everhour.apip). Next, set the ProfileSettings connection property to the connection string for Everhour (see below).

   Everhour API Profile Settings

   Obtain your API Key from your Everhour profile page (scroll to the bottom of the page).

   
4. Click Save & Test
5. Navigate to the Permissions tab in the Add Everhour 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 Everhour data from Polybase.

Create an External Data Source for Everhour 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 Everhour data.

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

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

Create an External Data Source for Everhour

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

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

Create External Tables for Everhour

After creating the external data source, use CREATE EXTERNAL TABLE statements to link to Everhour 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 Everhour Assignments would look similar to the following.

CREATE EXTERNAL TABLE Assignments(
  Id COLLATE [nvarchar](255) NULL,
  ProjectId COLLATE [nvarchar](255) NULL,
  ...
) WITH ( 
  LOCATION='API1.API.Assignments',
  DATA_SOURCE=ConnectAIInstance
);

Having created external tables for Everhour 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!