Ten ways to ensure Windows Azure-based applications are architected for success

Windows Azure SQL Database is a managed version of Microsoft SQL Server 2012, hosted by Microsoft in a Windows Azure datacenter. SQL Database is a core feature of the Windows Azure Platform.

SQL Database is a multi-tenanted system in which many database instances are hosted in a single SQL Server instance running on a physical server or node. Therefore, it has different performance characteristics than pure SQL Server. In particular, high data scalability and high performance are achieved by horizontally scaling the data into multiple instances or shards. To provide high availability and satisfy demanding SLAs, each SQL Database instance is stored as one primary replica and two secondary replicas. When a node fails, the primary and secondary copies it hosts are re-created on other nodes. SQL Database uses a quorum commit in which a commit is deemed successful as soon as the primary and one of the two secondary replicas have completed the commit.

This whitepaper describes the top ten issues that arise when deploying to SQL Database and explains how to mitigate these issues.