What's New in ADO.NET
The following features are new in ADO.NET in the .NET Framework 4.5.
The following features are new in the .NET Framework Data Provider for SQL Server in .NET Framework 4.5:
The ConnectRetryCount and ConnectRetryInterval connection string keywords (ConnectionString) let you control the idle connection resiliency feature.
Streaming support from SQL Server to an application supports scenarios where data on the server is unstructured. See SqlClient Streaming Support for more information.
Support has been added for asynchronous programming. See Asynchronous Programming for more information.
Connection failures will now be logged in the extended events log. For more information, see Data Tracing in ADO.NET.
SqlClient now has support for SQL Server's high availability, disaster recovery feature, AlwaysOn. For more information, see SqlClient Support for High Availability, Disaster Recovery.
When TrustServerCertificate is false and Encrypt is true, the server name (or IP address) in a SQL Server SSL certificate must exactly match the server name (or IP address) specified in the connection string. Otherwise, the connection attempt will fail. For more information, see the description of the Encrypt connection option in ConnectionString.
If this change causes an existing application to no longer connect, you can fix the application using one of the following:
Issue a certificate that specifies the short name in the Common Name (CN) or Subject Alternative Name (SAN) field. This solution will work for database mirroring.
Add an alias that maps the short name to the fully-qualified domain name.
Use the fully-qualified domain name in the connection string.
SqlClient supports Extended Protection. For more information about Extended Protection, see Connecting to the Database Engine Using Extended Protection.
SqlClient supports connections to LocalDB databases. For more information, see SqlClient Support for LocalDB.
Type System Version=SQL Server 2012; is new value to pass to the Type System Version connection property. The Type System Version=Latest; value is now obsolete and has been made equivalent to Type System Version=SQL Server 2008;. For more information, see ConnectionString.
SqlClient provides additional support for sparse columns, a feature that was added in SQL Server 2008. If your application already accesses data in a table that uses sparse columns, you should see an increase in performance. The IsColumnSet column of GetSchemaTable indicates if a column is a sparse column that is a member of a column set. GetSchema indicates if a column is a sparse column (see SQL Server Schema Collections for more information). For more information about sparse columns, see Using Sparse Columns.
The assembly Microsoft.SqlServer.Types.dll, which contains the spatial data types, has been upgraded from version 10.0 to version 11.0. Applications that reference this assembly may fail. For more information, see Breaking Changes to Database Engine Features.