Microsoft Azure Cosmos DB vs Microsoft Azure SQL Database

Question

I am developing a small app (via xamarin.forms), and it will be required to access information held in an online server at any moment from the user's device. I have managed to create an azure sql database, however I have not found any way to edit it from the app. I did some research on connecting to azure via REST method, and all the guides corresponded to azure cosmos DB. Apparently they are not the same thing. I am using visual studio, and not azure mobile apps.

My question is: What is the difference between azure sql and azure cosmos databases?

Which is more suitable for a small scale app with limited finances?

Solution

Azure Cosmos DB is a non-SQL database that provides access to information (JSON) quickly, with high availability, scalable and with global replication.

Microsoft Azure SQL Database as a Service offering with high compatibility to Microsoft SQL Server. That is, a Relational DBMS.

In your case it would be more convenient to use Cosmos DB because you can access the data (via JSON) without having to create a web service. And it have limitless scale. Your Azure Cosmos DB collections grow as your app grows. You can start with small data size and throughput of hundreds of requests per second.

Instead with Azure Database SQL you would have to create an ASP.Net Web API project to be able to access the data. (This could affect development time).

However, if you are not familiar with Cosmos DB it can affect development time as well.

You can find some examples here:

• Consuming an Azure Cosmos DB Document Database

• Build mobile applications with Xamarin and Azure Cosmos DB

• Going Global with Xamarin and Azure Cosmos DB

Comments

[David Makogon]

Not sure how you came to the conclusion the OP should use Cosmos DB over SQL Database, without seeing a single detail about their data schema, query needs, etc. Why wouldn't they need to create a web service? The alternative is to make database calls directly from their mobile app (why would you suggest that?). The choice of database isn't about removing an API layer.

[Farax]

I am not sure I agree that CosmosDB is fully NoSQL either.