By Patrik Bihammar, Azure Open Data Platform Lead at Microsoft Asia 

Today, applications are expected to be highly responsive and always available. They need to respond in real-time, store massive volumes of data, and make this data available to users in milliseconds. To achieve this, developers need to ensure millisecond response times, ultra-low latency, ultra-high availability, and instant and limitless scalability. 

That’s a tall ask and requires: 

  • Flexible data models that support both structured and unstructured data 
  • Limitless, immediate, and elastic scalability 
  • Low latency to ensure instant responsiveness across the globe 
  • Always-on high availability  

The good news is that Azure Cosmos DB, a horizontally scalable NoSQL database-as-a-service (DBaaS) platform, meets all these requirements and backs it up with financially backed SLAs. 

If you are reading this, you might already be familiar with the benefits of NoSQL databases such as the ones referenced in the title. In short, NoSQL in general and Azure Cosmos DB in particular, offer a number of key benefits over traditional relational databases, including “limitless” scalability, through horizontal partitioning, flexible schema, very low latency and very high availability.  

What is Azure Cosmos DB? 

Azure Cosmos DB is a multi-model NoSQL platform offered as a fully managed Database-as-Service (DBaaS) for modern apps. It offers SLA-backed ultra-low latency (<10ms) and 99.999% of availability, automatic and instant scalability and uniquely supports multiple open APIs (SQL/Core, MongoDB, Cassandra, Gremlin). 

As a managed database service, Azure Cosmos DB reduces an organization’s operational burden through automatic management, updates, and patching. It can also handle capacity management with cost-effective serverless and automatic scaling that responds to applications’ needs to match capacity with demand. This allows an organization to focus on their application not their database administration. 

Reasons for choosing Azure Cosmos DB

Migrating from existing NoSQL databases to Azure Cosmos DB DBaaS 

Due to these unique benefits, we often work with customers to help them migrate their existing MongoDB, Cassandra and Couchbase deployments to Azure Cosmos DB DBaaS.  

Migrating from MongoDB to Azure Cosmos DB  

There are several reasons why customers are migrating from MongoDB to Azure Cosmos DB, including scalability, the need for better HA/DR, the reduced operational burden because of managed service experience, and the fact that the application is being run or migrated to Azure. 

Here are some resources for MongoDB to Azure Cosmos DB migration guidance: 

Migrating from Cassandra to Azure Cosmos DB   
There are two managed Cassandra options available on Azure, the Azure Cosmos DB Cassandra API and the Apache Cassandra Managed Instance service.  

Here is some more detail about the differences and when to choose what option and why and how Symantec migrated their Cassandra clusters to Azure

diagram

Here is some guidance on how to migrate Cassandra to Azure: 

Migrating from Couchbase and AWS DynamoDB to Azure Cosmos DB 

Other common NoSQL migration scenarios and guidance include: 

Migrating from traditional relational databases to Azure Cosmos DB 

Finally, in addition to migrating from other NoSQL databases, many customers migrate from a traditional relational database to Azure Cosmos DB when they need to modernize their applications and want to leverage on a NoSQL database to ensure their application can scale.  

Here is some guidance on Migrating relational data into Azure Cosmos DB SQL API

Hopefully you will find this information useful for your NoSQL DBaaS migration journey! 

To get started you can try Azure Cosmos DB for free or use the Azure Cosmos DB free tier to get an account with the first 1000 RU/s and 25 GB of storage for free. 

Additional reading:  
1. Common use cases for NoSQL with Azure Cosmos DB | LinkedIn 

2. 5 Reasons Azure Cosmos DB is a great NoSQL DBaaS Platform | LinkedIn 

3. 8 Reasons you should consider DBaaS on Azure | LinkedIn