We’re excited to announce that Denali SNAC CTP1 adds support for the ODBC 3.8 features of the Microsoft ODBC DM (Driver Manager) introduced in Windows 7 and Windows Server 2008 R2.  Please refer to http://blogs.msdn.com/b/data/archive/2009/07/06/odbc-dm-3-80-in-windows-7-and-windows-server-2008-r2.aspx for a blog posting detailing the ODBC DM changes.

The ODBC 3.8 features supported in Denali SNAC are:

Streamed Output Parameters
Support retrieving output parameters in parts via SQLGetData when the output parameter was bound using SQLBindParameter.  This is extremely valuable when working with large data objects, such as varbinary(max), varchar(max), and nvarchar(max), since allocating an extremely large buffer may not be possible. 

ODBC C-Type Extensibility
Leveraging the functionality of C-type extensibility introduced in the ODBC 3.8 driver manager, Denali SNAC introduced SQL_C_SS_TIME2 and SQL_C_SS_TIMESTAMPOFFSET C-type structures.  The introduction of these 2 new C-types provides application developers a rich programming experience when using SQL Server Time and DatetimeOffset data types.  So, instead of binding these data types as SQL_C_BINARY and having to manually realize the byte sequence can cast to a struct, application developers can now directly bind these data types as the new C-types which automatically maps to the structs.

Asynchronous Connection Operation
Before ODBC 3.80, asynchronous mode was only supported on statement operations, such as SQLExecDirect and SQLGetData.  Leveraging the ODBC 3.8 feature, Denali SNAC extends this support to connection operations, such as SQLDriverConnect and SQLEndTran. It also allows applications to cancel connection operations via SQLCancelHandle, just as with SQLCancel on statement operations. 

Jimmy Wu
Microsoft SQL Server