What is Blob?

Definition: Blob (Binary Large Object). In simple terms, Blobs are nothing but files or content like Images, Videos, executable files, etc. In general, anything you store on your personal computer hard disk is BLOB.

• In Azure, every BLOB is stored in a Container and Containers belong to the Storage Account.
• You can add unlimited BLOBs in a container and an unlimited number of containers in a storage account.
• The following image depicts the hierarchy of BLOB.

Azure BLOB storage features:

• Azure Blob lets us store any kind of file and it also allows us to create an app to access those files.
• Each item in the blob storage will have a unique address.
• Blob storage is unstructured – meaning there’s no restriction on the type of data that is stored.
• We can,
  • Store Images
  • Store Videos
  • Store Text files
  • Write to log files
  • Stream Audio/Video directly from Blob
  • Store any kind of data like a backup, restore, archive, or disaster recovery.
  • More…
• Many Azure services use BLOB behind the scenes. E.g., the Azure cloud shell stores your files in the BLOB. Azure VMs also use BLOB for storage.
• BLOB and Containers support metadata in the form of Name-value pairs.
• BLOB doesn’t provide any feature of filtering, sorting, or searching the BLOB using metadata.
• BLOB storage APIs are REST-based and supported in many languages. You can create an application using this and can create and delete the BLOBs and containers, upload and download BLOBs and list all the BLOBs in a container.

What are the types of BLOB?

There are three types of BLOBs.

• Block BLOB: These are composed of blocks of different sizes, that can be uploaded independently. When you write data in Block BLOBs, you write it to the blocks, and then blocks are committed to BLOBs.
• Append BLOB: These are specialized block blobs that support only appending of the data. That means you cannot create or delete the data. These are helpful in cases of writing the logs.
• Page BLOB: These BLOBs store the Random-Access files. Any part of the file can be accessed at any time. This can store a virtual hard disk and can be served as a disk for Virtual Machine on Azure.

What is the Pricing Tier for BLOB storage?

• Hot: Low access time, and High access Cost
• Cool: Higher access time, low storage cost, compared to Hot storage
• Archive: Low costs and high access time.