Explore fundamentals of non-relational data in azure Flashcards
Azure Blob Storage
Azure Blob Storage is a service that enables you to store massive amounts of unstructured data as binary large objects, or blobs, in the cloud. Blobs are an efficient way to store data files in a format that is optimized for cloud-based storage, and applications can read and write them by using the Azure blob storage API.
Block blobs
Block blobs. A block blob is handled as a set of blocks. Each block can vary in size, up to 100 MB. A block blob can contain up to 50,000 blocks, giving a maximum size of over 4.7 TB. The block is the smallest amount of data that can be read or written as an individual unit. Block blobs are best used to store discrete, large, binary objects that change infrequently.
Page blobs
A page blob is organized as a collection of fixed-size 512-byte pages. A page blob is optimized to support random read and write operations; you can fetch and store data for a single page if necessary. A page blob can hold up to 8 TB of data. Azure uses page blobs to implement virtual disk storage for virtual machines.
Append blobs
An append blob is a block blob optimized to support append operations. You can only add blocks to the end of an append blob; updating or deleting existing blocks isn’t supported. Each block can vary in size, up to 4 MB. The maximum size of an append blob is just over 195 GB.
Blob tiers
- The Hot tier is the default. You use this tier for blobs that are accessed frequently. The blob data is stored on high-performance media.
- The Cool tier has lower performance and incurs reduced storage charges compared to the Hot tier. Use the Cool tier for data that is accessed infrequently. It’s common for newly created blobs to be accessed frequently initially, but less so as time passes. In these situations, you can create the blob in the Hot tier, but migrate it to the Cool tier later. You can migrate a blob from the Cool tier back to the Hot tier.
- The Archive tier provides the lowest storage cost, but with increased latency. The Archive tier is intended for historical data that mustn’t be lost, but is required only rarely. Blobs in the Archive tier are effectively stored in an offline state. Typical reading latency for the Hot and Cool tiers is a few milliseconds, but for the Archive tier, it can take hours for the data to become available. To retrieve a blob from the Archive tier, you must change the access tier to Hot or Cool. The blob will then be rehydrated. You can read the blob only when the rehydration process is complete.
Azure Data Lake Store Gen 2
Azure Data Lake Storage Gen2 is a newer version of this service that is integrated into Azure Storage; enabling you to take advantage of the scalability of blob storage and the cost-control of storage tiers, combined with the hierarchical file system capabilities and compatibility with major analytics systems of Azure Data Lake Store.
To create an Azure Data Lake Store Gen2 files system, you must enable the Hierarchical Namespace option of an Azure Storage account. You can do this when initially creating the storage account, or you can upgrade an existing Azure Storage account to support Data Lake Gen2. Be aware however that upgrading is a one-way process – after upgrading a storage account to support a hierarchical namespace for blob storage, you can’t revert it to a flat namespace.
Azure files
Azure Files is essentially a way to create cloud-based network shares, such as you typically find in on-premises organizations to make documents and other files available to multiple users. By hosting file shares in Azure, organizations can eliminate hardware costs and maintenance overhead, and benefit from high availability and scalable cloud storage for files.
You create Azure File storage in a storage account. Azure Files enables you to share up to 100 TB of data in a single storage account.
The maximum size of a single file is 1 TB, but you can set quotas to limit the size of each share below this figure.
After you’ve created a storage account, you can upload files to Azure File Storage using the Azure portal,or tools such as the AzCopy utility.
you can also use Azure File Sync service to synchronize locally cached copies of shared files with the data in Azure File Storage.\
Azure Files supports two common network file sharing protocols:
–Server Message Block (SMB) file sharing is commonly used across multiple operating systems (Windows, Linux, macOS).
–Network File System (NFS) shares are used by some Linux and macOS versions. To create an NFS share, you must use a premium tier age account and create and configure a virtual network through which access to the share can be controlled.
Azure Table Storage
Azure Table Storage is a NoSQL storage solution that makes use of tables containing key/value data items. Each item is represented by a row that contains columns for the data fields that need to be stored.
An Azure Table enables you to store semi-structured data. All rows in a table must have a unique key (composed of a partition key and a row key), and when you modify data in a table, a timestamp column records the date and time the modification was made; but other than that, the columns in each row can vary. Azure Table Storage tables have no concept of foreign keys, relationships, stored procedures, views, or other objects you might find in a relational database. Data in Azure Table storage is usually denormalized, with each row holding the entire data for a logical entity.
To help ensure fast access, Azure Table Storage splits a table into partitions. Partitioning is a mechanism for grouping related rows, based on common property or partition key. Partitioning not only helps to organize data, it can also improve scalability and performance in the following ways:
–Partitions are independent of each other, and can grow or shrink as rows are added to, or removed from, a partition. A table can contain any number of partitions.
–When you search for data, you can include the partition key in the search criteria. This helps to narrow down the volume of data to be examined and improves performance by reducing the amount of I/O (input and output operations, or reads and writes) needed to locate the data.
The key in an Azure Table Storage table comprises two elements; the partition key that identifies the partition containing the row, and a row key that is unique to each row in the same partition.
Azure Cosmos DB
Azure Cosmos DB supports multiple application programming interfaces (APIs) that enable developers to use the programming semantics of many common kinds of data store to work with data in a Cosmos DB database. The internal data structure is abstracted, enabling developers to use Cosmos DB to store and query data using APIs with which they’re already familiar.
Cosmos DB
Cosmos DB is a highly scalable database management system. Cosmos DB automatically allocates space in a container for your partitions, and each partition can grow up to 10 GB in size. Indexes are created and maintained automatically. There’s virtually no administrative overhead.
When to use Cosmos DB
Cosmos DB is a foundational service in Azure. Cosmos DB has been used by many of Microsoft’s products for mission critical applications at global scale, including Skype, Xbox, Microsoft 365, Azure, and many others. Cosmos DB is highly suitable for the following scenarios:
–IoT and telematics. : These systems typically ingest large amounts of data in frequent bursts of activity. Cosmos DB can accept and store this information quickly. The data can be used for analytics services such as Azure Machine Learning, Azure HDInsight, and Power BI.
–Retail and marketing. :Microsoft uses Cosmos DB for its own e-commerce platforms that run as part of Windows Store and Xbox Live. It’s also used in the retail industry for storing catalog data and for event sourcing in order processing pipelines.
–Gaming. : The database tier is a crucial component of gaming applications. Modern games perform graphical processing on mobile/console clients but rely on the cloud to deliver customized and personalized content like in-game stats, social media integration, and high-score leaderboards.
–Web and mobile applications. Azure Cosmos DB is commonly used within web and mobile applications, and is well suited for modeling social interactions, integrating with third-party services, and for building rich personalized experiences
Azure Cosmos DB APIs
Azure Cosmos DB supports multiple APIs, enabling developers to easily migrate data from commonly used NoSQL stores and apply their existing programming skills. When you provision a new Cosmos DB instance, you select the API that you want to use. The choice of API depends on many factors including, the type of data to be stored, the need to support existing applications, and the API skills of the developers who will work with the data store.
Core (SQL) API
The native API in Cosmos DB manages data in JSON document format, and despite being a NoSQL data storage solution, uses SQL syntax to work with the data.
MongoDB API
MongoDB is a popular open source database in which data is stored in Binary JSON (BSON) format. The Azure Cosmos DB MongoDB API enables developers to use MongoDB client libraries to and code to work with data in Azure Cosmos DB.
Table API
The Table API is used to work with data in key-value tables, similar to Azure Table Storage. The Azure Cosmos DB Table API offers greater scalability and performance than Azure Table Storage.
