How to connect PolyBase to CircleCI

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 API Driver for ODBC, you get access to your CircleCI data directly alongside your SQL Server data. This article describes creating an external data source and external tables to grant access to live CircleCI data using T-SQL queries.

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

The CData ODBC drivers offer unmatched performance for interacting with live CircleCI data using PolyBase due to optimized data processing built into the driver. When you issue complex SQL queries from SQL Server to CircleCI, the driver pushes down supported SQL operations, like filters and aggregations, directly to CircleCI and utilizes the embedded SQL engine to process unsupported operations (often SQL functions and JOIN operations) client-side. And with PolyBase, you can also join SQL Server data with CircleCI data, using a single query to pull data from distributed sources.

Connect to CircleCI

If you have not already, first specify connection properties in an ODBC DSN (data source name). This is the last step of the driver installation. You can use the Microsoft ODBC Data Source Administrator to create and configure ODBC DSNs. To create an external data source in SQL Server using PolyBase, configure a System DSN (CData CircleCI Sys is created automatically).

Using API Key Authentication

CircleCI uses personal API tokens to authenticate API requests. To generate a personal API token, log in to your CircleCI account, navigate to User Settings > Personal API Tokens, and click Create New Token. Copy the token value immediately as it is only shown once.

After setting the following connection properties, you are ready to connect:

• AuthScheme: Set this to APIKey.
• APIKey: Set this to your CircleCI personal API token.

Example connection string:

Profile=C:\profiles\CircleCI.apip;AuthScheme=APIKey;ProfileSettings='APIKey=your_personal_api_token';

Click "Test Connection" to ensure that the DSN is connected to CircleCI properly. Navigate to the Tables tab to review the table definitions for CircleCI.

Create an External Data Source for CircleCI Data

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

Creating a Master Encryption Key

Execute the following SQL command to create a new master key, 'ENCRYPTION,' to encrypt the credentials for the external data source.

CREATE MASTER KEY ENCRYPTION BY PASSWORD = 'password';

Creating a Credential Database

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

NOTE: Since CircleCI does not require a User or Password to authenticate, you may use whatever values you wish for IDENTITY and SECRET.

CREATE DATABASE SCOPED CREDENTIAL api_creds
WITH IDENTITY = 'username', SECRET = 'password';

Create an External Data Source for CircleCI

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

• Set the LOCATION parameter , using the DSN and credentials configured earlier.

For CircleCI, set SERVERNAME to the URL or address for your server (e.g. 'localhost' or '127.0.0.1' for local servers; the remote URL for remote servers). Leave PORT empty. PUSHDOWN is set to ON by default, meaning the ODBC Driver can leverage server-side processing for complex queries.

CREATE EXTERNAL DATA SOURCE cdata_api_source
WITH ( 
  LOCATION = 'odbc://SERVER_URL',
  CONNECTION_OPTIONS = 'DSN=CData CircleCI Sys',
  -- PUSHDOWN = ON | OFF,
  CREDENTIAL = api_creds
);

Create External Tables for CircleCI

After creating the external data source, use CREATE EXTERNAL TABLE statements to link to CircleCI data from your SQL Server instance. The table column definitions must match those exposed by the CData API Driver for ODBC. You can refer to the Tables tab of the DSN Configuration Wizard to see the table definition.

Sample CREATE TABLE Statement

The statement to create an external table based on a CircleCI Artifacts would look similar to the following:

CREATE EXTERNAL TABLE Artifacts(
   [nvarchar](255) NULL,
   [nvarchar](255) NULL,
  ...
) WITH ( 
  LOCATION='Artifacts',
  DATA_SOURCE=cdata_api_source
);

Having created external tables for CircleCI in your SQL Server instance, you are now able to query local and remote data simultaneously. Thanks to built-in query processing in the CData ODBC Driver, you know that as much query processing as possible is being pushed to CircleCI, freeing up local resources and computing power. Download a free, 30-day trial of the ODBC Driver for CircleCI and start working with live CircleCI data alongside your SQL Server data today.