Azure Storage Table Storage Concepts

Introduction to Table Storage

Azure Table Storage is a NoSQL key-value store that can store large amounts of structured, non-relational data. It's a cost-effective storage solution for applications that require flexible data models and rapid development.

Key Concepts

• Account: An Azure Storage account provides a unique namespace for your Azure Storage data. All objects in a storage account are accessible via a RESTful HTTP or HTTPS interface.
• Table: A table is a collection of entities. It is similar to a relational database table, but without a predefined schema. You can insert entities with different properties into the same table.
• Entity: An entity is a set of properties, similar to a row in a database table. An entity can have up to 252 properties, plus the PartitionKey and RowKey.
• Properties: Properties are name-value pairs within an entity. Property names are strings, and values can be one of the supported primitive data types (e.g., String, Int32, Int64, Double, Boolean, DateTime, GUID, Binary, Edm.Binary, Edm.Boolean, Edm.Byte, Edm.DateTime, Edm.Decimal, Edm.Double, Edm.Guid, Edm.Int32, Edm.Int64, Edm.String).
• PartitionKey: This property is a string that defines the partition for an entity. Entities with the same PartitionKey are logically grouped together and stored in the same partition. This key is used for performance and scalability.
• RowKey: This property is a string that uniquely identifies an entity within a partition. The combination of PartitionKey and RowKey must be unique for each entity.

Schema Flexibility

Unlike traditional relational databases, Table Storage does not enforce a schema on entities. This means that entities within the same table do not need to have the same set of properties. This flexibility is ideal for handling evolving data requirements and diverse data structures.

Scalability and Performance

Table Storage is designed for massive scale. By partitioning your data effectively using the PartitionKey, you can achieve high throughput and availability. Queries that target entities within the same partition are generally faster.

Use Cases

• Storing user data for a web application.
• Storing metadata for blobs or files.
• Storing telemetry data from devices.
• Storing game state for a multiplayer game.

Example Entity Structure

{
  "PartitionKey": "Customer",
  "RowKey": "12345",
  "Name": "John Doe",
  "Email": "john.doe@example.com",
  "CreatedDate": "2023-10-27T10:00:00Z",
  "IsActive": true
}
        

Querying Data

You can query entities using OData filters. Queries can be scoped to a specific table or even a specific partition. Table Storage supports point queries (retrieving a single entity by its PartitionKey and RowKey) and range queries within a partition.

Data Types

Table Storage supports a variety of primitive data types. When storing data, it's important to ensure that the values conform to the expected type. The following are some of the common data types:

• Edm.String
• Edm.Int32
• Edm.Int64
• Edm.Double
• Edm.Boolean
• Edm.DateTime
• Edm.Guid
• Edm.Binary