'''Microsoft Azure SQL Database''' (formerly '''SQL Azure''', '''SQL Server Data Services''', '''SQL Services''', '''Windows Azure SQL Database''') is a [[cloud computing|cloud-based]] [[software as a service|service]] from [[Microsoft]] offering data-storage capabilities (similar to [[Amazon Relational Database Service]]) as a part of the [[Azure Services Platform]]. Unlike similar cloud-based databases, SQL Database allows users to make [[relational database|relational]] queries against stored data, which can either be [[structured data|structured]] or [[semi-structured data|semi-structured]], or even [[unstructured data|unstructured document]]s.<ref name="faq">{{cite web | url = http://www.microsoft.com/azure/faq.mspx#sql | title = Microsoft SQL Services FAQ | publisher = [[Microsoft]] | accessdate = 2009-04-16}}</ref> SQL Database features querying data, search, data analysis and data synchronization.<ref name="faq"/>
SQL Database usesshares a common code base with [[Microsoft SQL Server]].. It provides [[high availability]] by storing multiple copies of databases, [[business continuity]] and [[disaster recovery]] with backups and geo-replication, elastic scale and rapid provisioning. It has built-in data protection and security features. It exposes a subset of the full SQL Server functionality, including only a subset of the data types — including string, numeric, date and boolean.<ref name="ssds">{{cite web|url=http://blogs.msdn.com/access/archive/2008/03/06/sql-server-data-services.aspx |title=SQL Server Data Services |publisher=[[MSDN]] Blogs |author=Ryan McMinn |accessdate=2008-03-07 |deadurl=yes |archiveurl=http://web.archive.org/web/20080311003352/http://blogs.msdn.com:80/access/archive/2008/03/06/sql-server-data-services.aspx |archivedate=March 11, 2008 }}</ref> It uses an [[XML]]-based format for data transfer.<ref name="faq"/> Like [[Microsoft SQL Server]], SQL Database uses [[T-SQL]] as the query language and [[Tabular Data Stream]] (TDS) as the protocol to access the service over the Internet.<ref name="faq"/><ref>{{cite web | url = http://www.microsoft.com/azure/data.mspx | title = SQL Server Data Services | publisher = [[Microsoft]] | accessdate = 2009-04-16}}</ref> (The product does not provide a [[REST]]-based [[API]] to access the service over [[HTTP]]<ref name="faq"/> - [[Microsoft]] recommends using [[ADO.NET Data Services]] for this purpose.<ref name="faq"/>)
