SQL Azure is cloud base database platform provided by Microsoft. You can query database, access it. Your database will be hosted online and its DBA tasks will be taken care by Microsoft. I.e. you don’t need to bother about administration and maintain your database.
By using SQL Azure user can have there database online and they need no to be worried about database maintenance. SQL Azure platform can be useful for software aided services applications.
It sues TSQL to fetch the data and Tabular Data stream to access it on internet. You don’t need to manage infrastructure. Microsoft will charge from you for maintaining the database online.
SQL Server Quest 