Azure Storage Documentation

Delete Blobs in Azure Storage

This document provides guidance on how to delete blobs from Azure Blob Storage using various methods.

Methods for Deleting Blobs

You can delete blobs programmatically using Azure SDKs, the Azure CLI, Azure PowerShell, or through the Azure portal.

1. Using the Azure Portal

The Azure portal offers a user-friendly interface for managing your storage account and its contents.

1. Navigate to your storage account in the Azure portal.
2. Select "Containers" under "Data storage".
3. Choose the container that holds the blob you wish to delete.
4. Locate the blob in the list.
5. Select the blob by clicking the checkbox next to its name.
6. Click the "Delete" button that appears at the top of the list.
7. Confirm the deletion in the dialog box.

2. Using Azure CLI

The Azure Command-Line Interface (CLI) is a powerful tool for automating Azure resource management.

To delete a single blob:

az storage blob delete --account-name  --container-name  --name  --account-key 

To delete multiple blobs using a prefix:

az storage blob delete-batch --account-name  --destination / --pattern "*" --account-key 

Replace the placeholders with your actual storage account name, container name, blob name, prefix, and account key.

3. Using Azure PowerShell

Azure PowerShell provides another scripting option for managing Azure resources.

To delete a single blob:

Remove-AzStorageBlob -Container  -Blob  -Context (New-AzStorageContext -StorageAccountName "" -StorageAccountKey "")

To delete multiple blobs with a prefix:

Get-AzStorageBlob -Container  -Prefix "" | Remove-AzStorageBlob -Context (New-AzStorageContext -StorageAccountName "" -StorageAccountKey "")

Remember to substitute the placeholder values.

4. Using Azure SDKs (Example: .NET)

You can integrate blob deletion into your applications using the Azure Storage SDKs.

Here's a C# example using the Azure.Storage.Blobs NuGet package:

using Azure.Storage.Blobs;
using Azure;

// Replace with your connection string
string connectionString = "YOUR_AZURE_STORAGE_CONNECTION_STRING";
string containerName = "my-container";
string blobName = "my-blob.txt";

try
{
    // Create a BlobServiceClient object
    BlobServiceClient blobServiceClient = new BlobServiceClient(connectionString);

    // Get a BlobContainerClient
    BlobContainerClient containerClient = blobServiceClient.GetBlobContainerClient(containerName);

    // Get a BlobClient
    BlobClient blobClient = containerClient.GetBlobClient(blobName);

    // Delete the blob
    Response response = await blobClient.DeleteAsync();

    Console.WriteLine($"Blob '{blobName}' deleted successfully.");
}
catch (RequestFailedException ex)
{
    Console.WriteLine($"Error deleting blob: {ex.Message}");
}
        

Deleting Previous Blob Versions

If blob versioning is enabled for your container, deleting a blob does not permanently remove it. Instead, it marks the current version as the latest. To permanently delete previous versions:

• You can explicitly delete specific versions using the SDKs or CLI by providing the version ID.
• Configure blob lifecycle management policies to automatically delete older versions.

Best Practices for Deletion

• Use Versioning Wisely: Enable versioning if you need to recover from accidental deletions, but be aware of the storage costs associated with multiple versions.
• Lifecycle Management: Implement lifecycle management policies to automate the deletion of old or unnecessary data, optimizing storage costs.
• Permissions: Ensure that the identity performing the deletion has the necessary permissions (e.g., "Storage Blob Data Contributor" role).
• Batch Operations: For deleting a large number of blobs, use batch deletion commands or SDK methods to improve efficiency.

Further Reading

• Blob Versioning in Azure Blob Storage
• Lifecycle Management for Azure Blob Storage