Maintain indexing policies in production by using ARM templates

In Microsoft Azure Cosmos DB, maintaining indexing policies is crucial for optimizing query performance and efficiently managing your data. Azure Resource Manager (ARM) templates provide a convenient way to manage and deploy your Cosmos DB resources, including indexing policies, in a consistent and reproducible manner. In this article, we will explore how to maintain indexing policies in production using ARM templates.

Indexing policies in Azure Cosmos DB

Indexing policies in Azure Cosmos DB allow you to define which properties of your documents should be indexed for efficient querying. By carefully designing and managing your indexing policies, you can significantly improve the performance of your queries. ARM templates, on the other hand, enable you to define and manage your Azure resources as code. This makes it easier to version control, deploy, and maintain your Cosmos DB resources, including indexing policies.

Steps to maintain indexing policies in production using ARM templates:

1. Define your indexing policy as code: In your ARM template, define the indexing policy for your Cosmos DB containers. You can specify the indexing policy at the container level or override it at the item level. Here’s an example of a container-level indexing policy:

"resources": [
{
"type": "Microsoft.DocumentDB/databaseAccounts/apis/databases/containers",
"name": "[concat(parameters('databaseAccountName'), '/MyDatabase/MyContainer')]",
"apiVersion": "2021-03-01",
"location": "[parameters('location')]",
"properties": {
"resource": {
"id": "MyContainer"
},
"options": {
"indexingPolicy": {
"indexingMode": "consistent",
"includedPaths": [
{
"path": "/*"
}
],
"excludedPaths": [
{
"path": "/\"_etag\"/?"
}
]
}
}
},
"dependsOn": [
"[resourceId('Microsoft.DocumentDB/databaseAccounts/apis/databases', parameters('databaseAccountName'), 'MyDatabase')]"
]
}
]

In this example, the indexing policy specifies that all paths should be indexed, except for the “_etag” property.

2. Version control your ARM template: Use a version control system, such as Git, to manage your ARM template. This ensures that you have a history of changes made to the indexing policies over time.
3. Deploy your ARM template: Use Azure PowerShell, Azure CLI, or Azure DevOps to deploy your ARM template to your production environment. Make sure to include the necessary parameters, such as the Cosmos DB account name and location.
4. Monitor and optimize indexing policies: Once your indexing policies are deployed, monitor the query performance and adjust the indexing policies as needed. Analyze the query execution times and consider adding or modifying index paths to improve performance. Remember that indexing policies can have a significant impact on query performance, so periodically review and optimize them.

By maintaining indexing policies in production using ARM templates, you ensure consistency and reproducibility in your deployment process. It becomes easier to manage, version control, and automate the deployment of your Cosmos DB resources. With proper monitoring and optimization, you can continuously improve the query performance of your production environment.

In conclusion, utilizing ARM templates to maintain indexing policies in Azure Cosmos DB simplifies the management and deployment of your indexing policies. With the ability to define indexing policies as code, version control them, and deploy them consistently, you can efficiently manage your Cosmos DB resources in production. Remember to regularly monitor and optimize your indexing policies to achieve optimal query performance.