Azure sqldatabase series 2--azure SQL Database vs. SQL Server

(content is organized from the MSDN Azure SQL Database topic section) similar to SQL Server, Azure SQL database accesses a tabular data flow (TDS) interface for Transact-SQL-based databases. This allows your database applications to use Azure SQL database in the same way that they use SQL Server.

Unlike SQL Server management, Azure SQL database extracts logical management from physical management; you continue to manage databases, logins, users, and roles, but Microsoft manages and configures physical hardware such as hard drives, servers, and storage. Because Microsoft handles all physical management, there are some differences between Azure SQL Database and SQL Server in terms of management, provisioning, Transact-SQL support, programming models, and features.

The following table summarizes some of these major differences:

Database size
Azure SQL Database currently offers the following versions:

Web Edition, 1 GB and 5 GB, respectively.

Business Edition, respectively, 10, 20, 30, 40, 50, 100, GB size.

The premium version supports databases with a maximum capacity of.

Be sure to look at the size of your database and what data storage limits it uses for Azure SQL. If your database is larger than the Azure SQL database size limit, you must examine the database and determine whether you can split the database into smaller databases (that is, shards), or move large data into the Window Azure Blob storage space.

Identity verification
Azure SQL Database supports only SQL authentication. You must consider whether you need to make changes to the authentication schema that your application uses.

SQL Server Database Version
Azure SQL Database is based on SQL Server 2014. If you want to migrate SQL Server 2000 or SQL Server 2005 databases to Azure SQL database, you must make sure that your database is compatible with SQL Server 2014. You'll find that the best approach is to migrate from SQL Server 2014 to Azure SQL Database. You can upgrade to SQL Server 2014 internally before migrating to Azure SQL Database.

Schema
Azure SQL Database does not support heaps. All tables must have a clustered index before the data can be inserted.

Transact-SQL can support
Microsoft Azure SQL Database supports a subset of the Transact-SQL languages. Before you deploy databases to Azure SQL database, you must modify the script so that it includes only supported Transact-SQL statements.

Use Statement
In Azure SQL database, the USE statement does not switch between databases. To change the database, you must connect directly to the database.

Price
The price of your Azure SQL database subscription is based on the database and the version you are using. The amount of data transferred to and from the data center at any time is subject to additional charges. You can choose whether to run your application code internally and connect to Azure SQL database in your datacenter, or run your application code in Azure, which is hosted in the same datacenter as your azure SQL database. Run application code in Azure to avoid additional data transfer charges.

Functional limitations
Azure SQL Database does not currently support some SQL Server features. These include: SQL Agent, full-text search, Service Broker, Backup and restore, common language runtime, and SQL Server integration Services.