Blob storage (block, append, page) in Azure - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to create a block blob client in Azure Blob Storage.

Azure

blob_client = container_client.get_blob_client([1])

Drag options to blanks, or click blank then click option'

A'blockblob1'

B'appendblob'

C'pageblob'

D'blobcontainer'

Attempts:

3 left

💡 Hint

Common Mistakes

Using blob type instead of blob name

Using container name instead of blob name

To create a block blob client, you specify the blob name as a string. The type is determined by the client method, so the blob name should be the actual blob's name.

2fill in blank

medium

Complete the code to upload data to an append blob.

Azure

append_blob_client = container_client.get_blob_client([1])
append_blob_client.create_append_blob()
append_blob_client.append_block(data)

Drag options to blanks, or click blank then click option'

A'blockblob1'

B'container1'

C'pageblob1'

D'appendblob1'

Attempts:

3 left

💡 Hint

Common Mistakes

Using block blob name for append blob client

Using container name instead of blob name

Append blobs are used for append operations like logs. The blob name should reflect the append blob you want to create.

3fill in blank

hard

Fix the error in the code to upload a page blob with correct size alignment.

Azure

page_blob_client = container_client.get_blob_client([1])
page_blob_client.create_page_blob(size=5120)
page_blob_client.upload_page(data, offset=0, length=512)

Drag options to blanks, or click blank then click option'

A'blockblob1'

B'pageblob1'

C'appendblob1'

D'container1'

Attempts:

3 left

💡 Hint

Common Mistakes

Using block or append blob names

Incorrect size alignment for page blob

Page blobs require the size to be a multiple of 512 bytes. The blob name must be for a page blob.

4fill in blank

hard

Fill both blanks to create and upload a block blob with data.

Azure

block_blob_client = container_client.get_blob_client([1])
block_blob_client.upload_blob([2], overwrite=True)

Drag options to blanks, or click blank then click option'

A'blockblob2'

Bdata

C'appendblob2'

D'pageblob2'

Attempts:

3 left

💡 Hint

Common Mistakes

Using wrong blob type names

Passing blob name instead of data to upload_blob

The first blank is the block blob name. The second blank is the data variable holding the content to upload.

5fill in blank

hard

Fill all three blanks to create an append blob, append data, and set metadata.

Azure

append_blob_client = container_client.get_blob_client([1])
append_blob_client.create_append_blob()
append_blob_client.append_block([2])
append_blob_client.set_blob_metadata([3])

Drag options to blanks, or click blank then click option'

A'appendblob3'

Blog_data

C{'source': 'app', 'type': 'log'}

D'blockblob3'

Attempts:

3 left

💡 Hint

Common Mistakes

Using block blob name

Passing wrong data variable

Incorrect metadata format

The first blank is the append blob name. The second is the data variable to append. The third is a dictionary with metadata keys and values.

Practice

1. Which type of Azure Blob storage is best suited for storing large files that are uploaded in blocks and can be updated by replacing blocks?

easy

A. Append blob

B. Page blob

C. Block blob

D. File blob

Solution

1. Step 1: Understand block blob usage

   Block blobs are designed to store large files uploaded in blocks and allow updating by replacing blocks.

2. Step 2: Compare with other blob types

   Append blobs are for append-only operations, and page blobs are optimized for random read/write operations, not block uploads.

3. Final Answer:

   Block blob -> Option C

4. Quick Check:

   Block blob = large files in blocks [OK]

Hint: Block blobs store large files in blocks, perfect for uploads [OK]

Common Mistakes:

• Confusing append blob with block blob
• Thinking page blob is for block uploads
• Selecting non-existent blob types

2. Which of the following is the correct way to create an append blob using Azure CLI?

easy

A. az storage blob create --container-name mycontainer --name myappendblob --type AppendBlob

B. az storage blob create --container-name mycontainer --name myappendblob --type BlockBlob

C. az storage blob create --container-name mycontainer --name myappendblob --type PageBlob

D. az storage blob create --container-name mycontainer --name myappendblob --type FileBlob

Solution

1. Step 1: Identify correct blob type syntax

   The Azure CLI uses --type AppendBlob to create an append blob.

2. Step 2: Verify other options

   BlockBlob and PageBlob are valid types but not for append blobs; FileBlob is invalid.

3. Final Answer:

   az storage blob create --container-name mycontainer --name myappendblob --type AppendBlob -> Option A

4. Quick Check:

   Append blob creation uses --type AppendBlob [OK]

Hint: Use --type AppendBlob to create append blobs in Azure CLI [OK]

Common Mistakes:

• Using BlockBlob type for append blobs
• Using PageBlob type for append blobs
• Using invalid blob type names

3. Consider this code snippet using Azure SDK to upload data to a blob:

blob_client = container_client.get_blob_client('myblob')
blob_client.upload_blob(data, blob_type='PageBlob')

What will happen if the data size is not a multiple of 512 bytes?

medium

A. Upload will fail with an error about data size alignment

B. Upload will succeed with data padded to 512-byte boundaries

C. Upload will succeed but truncate extra bytes

D. Upload will convert data to block blob automatically

Solution

1. Step 1: Understand page blob requirements

   Page blobs require data size to be a multiple of 512 bytes for alignment.

2. Step 2: Analyze upload behavior

   If data size is not aligned, the upload will fail with an error about size alignment.

3. Final Answer:

   Upload will fail with an error about data size alignment -> Option A

4. Quick Check:

   Page blob data size must be multiple of 512 bytes [OK]

Hint: Page blobs need 512-byte aligned data size [OK]

Common Mistakes:

• Assuming automatic padding of data
• Thinking upload truncates data silently
• Believing blob type auto-conversion occurs

4. You have an append blob but your application tries to overwrite existing data instead of appending. What is the likely cause and fix?

medium

A. Using page blob API calls on append blob

B. Using append_block method instead of upload_blob

C. Creating the blob as a block blob instead of append blob

D. Using upload_blob with overwrite=True instead of append_block method

Solution

1. Step 1: Identify append blob usage

   Append blobs require using append_block to add data without overwriting.

2. Step 2: Analyze the overwrite behavior

   Using upload_blob with overwrite=True replaces existing data, not appends.

3. Final Answer:

   Using upload_blob with overwrite=True instead of append_block method -> Option D

4. Quick Check:

   Append blobs append with append_block, not upload_blob overwrite [OK]

Hint: Use append_block to add data, not upload_blob overwrite [OK]

Common Mistakes:

• Confusing append_block and upload_blob methods
• Creating wrong blob type
• Using page blob APIs on append blobs

5. You need to design a system that stores virtual machine disks requiring frequent random read/write operations with low latency. Which Azure blob type should you choose and why?

hard

A. Append blob, because it allows efficient appending of logs

B. Page blob, because it supports random read/write with 512-byte pages

C. Block blob, because it supports large file uploads in blocks

D. File blob, because it supports file system semantics

Solution

1. Step 1: Identify requirements for VM disks

   VM disks need frequent random read/write with low latency and page-level updates.

2. Step 2: Match blob type to requirements

   Page blobs support random read/write operations in 512-byte pages, ideal for VM disks.

3. Step 3: Exclude other blob types

   Block blobs are for large uploads, append blobs for append-only logs, and file blob is not a valid Azure blob type.

4. Final Answer:

   Page blob, because it supports random read/write with 512-byte pages -> Option B

5. Quick Check:

   VM disks use page blobs for random read/write [OK]

Hint: Page blobs support random read/write, perfect for VM disks [OK]

Common Mistakes:

• Choosing block blob for VM disks
• Confusing append blob with page blob
• Selecting non-existent file blob type