Query Cosmos DB Data through ODBC in Node.js

Node.js is a JavaScript runtime environment that allows you to run JavaScript code outside of a browser. With the CData ODBC Driver for Cosmos DB, you can access live Cosmos DB data from Node.js apps and scripts. In this article, we walk through installing node-odbc and the required tools to create a simple Node.js app with access to live Cosmos DB data.

With built-in optimized data processing, the CData ODBC Driver offers unmatched performance for interacting with live Cosmos DB data in Node.js. When you issue complex SQL queries from Node.js to Cosmos DB, the driver pushes supported SQL operations, like filters and aggregations, directly to Cosmos DB and utilizes the embedded SQL engine to process unsupported operations client-side (often SQL functions and JOIN operations).

Connecting to Cosmos DB Data

If you have not already done so, provide values for the required connection properties in the data source name (DSN). You can use the built-in Microsoft ODBC Data Source Administrator to configure the DSN. This is also the last step of the driver installation. See the "Getting Started" chapter in the help documentation for a guide to using the Microsoft ODBC Data Source Administrator to create and configure a DSN.

To obtain the connection string needed to connect to a Cosmos DB account using the SQL API, log in to the Azure Portal, select Azure Cosmos DB, and select your account. In the Settings section, click Connection String and set the following values:

• AccountEndpoint: The Cosmos DB account URL from the Keys blade of the Cosmos DB account
• AccountKey: In the Azure portal, navigate to the Cosmos DB service and select your Azure Cosmos DB account. From the resource menu, go to the Keys page. Find the PRIMARY KEY value and set AccountKey to this value.

Building node-odbc

In order to connect to Cosmos DB through the CData ODBC Driver, you need to build node-odbc manually (after installing the required tools).

Installing the Required Tools

The following commands install the tools required to build node-odbc (note the -g parameter, which installs the tools globally).

npm i -g windows-build-tools
npm i -g node-gyp

Building node-odbc

After installing the required tools, create a directory for the Node.js app and install odbc (which builds the binary for us to use in our Node.js script).

mkdir nodeodbc
cd nodeodbc
npm i -g node

Querying Cosmos DB from Node.js

With the ODBC Driver installed, a DSN Configured, and node-odbc built, we are ready to query live Cosmos DB data from a Node.js app. The sample code below connects to a specific DSN and queries the Customers table.

myscript.js

const odbc = require('odbc');

async function queryCosmosDB() {
    const connection = await odbc.connect(`DSN=CData CosmosDB Source`);
    const data = await connection.query('SELECT City, CompanyName FROM Customers');
    console.log(data);
}

queryCosmosDB();

Once you write the app, use node to execute the script:

node myscript.js

Download a free, 30-day trial of the CData ODBC Driver for Cosmos DB and start working with your live Cosmos DB data in Node.js. Reach out to our Support Team if you have any questions.