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Comparing SQL Database with SQL Server in Azure
Virtual Machines
The decision to use SQL Database or SQL Server in Azure Virtual Machines can be difficult. On the one
hand, SQL Database is ideal for reducing the administrative cost related to provisioning and managing
relational databases because many tasks
such as upgrades, patching, backups, and business continuity
scenarios are handled automatically. On the other hand, SQL Server in Azure Virtual Machines
provides the option to migrate or extend existing on-premises SQL Server workloads to Azure. Even
though there are additional administrative costs with running SQL Server in Azure Virtual Machines,
the ability to maintain fine-grained control over those tasks could be worthwhile for some users and
scenarios.
Although SQL Database and SQL Server are similar in many areas,
some key differences exist, most
notably SQL Server features that are not currently supported in SQL Database, such as the following:
Windows authentication.
FILESTREAM data.
Database mirroring.
Extended stored procedures.
SQL Server Agent/Jobs.
SQL Server Reporting Services (SSRS) and SQL Server Integration Services (SSIS) are not
supported. Alternatively, run a SQL Server on-premises or in an Azure VM and connect to a SQL
database.
T-SQL features
USE statement is not supported. To change databases, a new connection must be established.
Common language runtime (CLR).
Cross-database queries using three or four part names.
Note The limitations listed above are only a few of those of which you should be aware when
working with SQL Database.
For a complete list, please see the guidance on MSDN at
https://azure.microsoft.com/documentation/articles/sql-database-general-limitations/
. You can also
find the related T-SQL statement references at
https://azure.microsoft.com/documentation/articles/sql-database-transact-sql-information/.
Additionally, elastic database query provides limited support for querying across databases in SQL
Database. Please see
https://azure.microsoft.com/blog/querying-remote-databases-in-azure-sql-
db/
for additional information.
There are many factors to consider when choosing between SQL Database and
SQL Server in Azure
Virtual Machines: database size, existing application versus new application, level of administrative
control (including hardware infrastructure), business continuity strategy, and hybrid scenarios, just to
name a few. SQL Database is often the right solution for cloud-designed applications that are not
using unsupported features and for which near-zero administration is a key priority.
SQL Server in
Azure Virtual Machines is often the right choice for new or existing applications that require a high
level of control and customization (that is, full compatibility with SQL Server) and for which there is a
desire to no longer maintain on-premises hardware.
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Database alternatives
There are many database options available in the market today. The Microsoft Azure platform makes
it easy to run a wide range of popular databases—you don’t have to run SQL Database or Microsoft
SQL Server. As discussed in Chapter 3, you can run the software of your choosing on an
Azure VM,
including the database platform you desire. You also have the option to run MySQL as a service via
Microsoft’s partnership with SuccessBrick’s ClearDb offering. If a relational database management
system (RDBMS) is not what you’re after, using a NoSQL service such as DocumentDB or Azure Table
storage is also an option.
MySQL
Another popular relational database is MySQL. Microsoft has collaborated with SuccessBricks
to bring
SuccessBricks’ ClearDb database as a service for MySQL to the Azure platform.
To get started, open the Azure portal and click the green New button in the upper-left corner. From
the Data + Storage category, find the MySQL Database feature in the list of available services, as
shown in Figure 6-15.
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Figure 6-15 Creating a new MySQL database.
When the New MySQL Database blade opens (Figure 6-16), you’ll have the opportunity to provide the
necessary details about your new MySQL database, including the following:
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